diff --git a/.ci/bwcVersions b/.ci/bwcVersions
index 5246115d0b693..b72d3b4089b97 100644
--- a/.ci/bwcVersions
+++ b/.ci/bwcVersions
@@ -46,6 +46,7 @@ BWC_VERSION:
   - "1.3.7"
   - "1.3.8"
   - "1.3.9"
+  - "1.3.10"
   - "2.0.0"
   - "2.0.1"
   - "2.0.2"
@@ -62,3 +63,4 @@ BWC_VERSION:
   - "2.5.0"
   - "2.5.1"
   - "2.6.0"
+  - "2.6.1"
diff --git a/.github/workflows/code-hygiene.yml b/.github/workflows/code-hygiene.yml
deleted file mode 100644
index a1adbb8a87507..0000000000000
--- a/.github/workflows/code-hygiene.yml
+++ /dev/null
@@ -1,14 +0,0 @@
-name: Code Hygiene
-
-on: [pull_request]
-
-jobs:
-  linelint:
-    runs-on: ubuntu-latest
-    name: Check if all files end in newline
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v2
-
-      - name: Linelint
-        uses: fernandrone/linelint@0.0.4
diff --git a/.github/workflows/github-merit-badger.yml b/.github/workflows/github-merit-badger.yml
new file mode 100644
index 0000000000000..ee00e62da2f08
--- /dev/null
+++ b/.github/workflows/github-merit-badger.yml
@@ -0,0 +1,20 @@
+name: github-merit-badger
+on:
+  pull_request_target:
+    types:
+     - opened
+
+jobs:
+  call-action:
+    runs-on: ubuntu-latest
+    permissions:
+      pull-requests: write
+    steps:
+      - uses: aws-github-ops/github-merit-badger@v0.0.98
+        id: merit-badger
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          badges: '[first-time-contributor,repeat-contributor,valued-contributor,seasoned-contributor,all-star-contributor,distinguished-contributor]'
+          thresholds: '[0,3,6,13,25,50]'
+          badge-type: 'achievement'
+          ignore-usernames: '[opensearch-ci-bot, dependabot, opensearch-trigger-bot]'
diff --git a/.linelint.yml b/.linelint.yml
deleted file mode 100644
index ec947019f8ab6..0000000000000
--- a/.linelint.yml
+++ /dev/null
@@ -1,49 +0,0 @@
-# 'true' will fix files
-autofix: true
-
-ignore:
-  - .git/
-  - .gradle/
-  - .idea/
-  - '*.sha1'
-  - '*.txt'
-  - 'CHANGELOG.md'
-  - '.github/CODEOWNERS'
-  - 'buildSrc/src/testKit/opensearch.build/LICENSE'
-  - 'buildSrc/src/testKit/opensearch.build/NOTICE'
-  - 'server/licenses/apache-log4j-extras-DEPENDENCIES'
-  # Empty files
-  - 'buildSrc/src/integTest/resources/org/opensearch/gradle/internal/fake_git/remote/build.gradle'
-  - 'buildSrc/src/integTest/resources/org/opensearch/gradle/internal/fake_git/remote/distribution/archives/oss-darwin-tar/build.gradle'
-  - 'buildSrc/src/integTest/resources/org/opensearch/gradle/internal/fake_git/remote/distribution/bwc/bugfix/build.gradle'
-  - 'buildSrc/src/integTest/resources/org/opensearch/gradle/internal/fake_git/remote/distribution/bwc/minor/build.gradle'
-  - 'buildSrc/src/main/resources/buildSrc.marker'
-  - 'buildSrc/src/testKit/opensearch-build-resources/settings.gradle'
-  - 'buildSrc/src/testKit/opensearch.build/settings.gradle'
-  - 'buildSrc/src/testKit/reaper/settings.gradle'
-  - 'buildSrc/src/testKit/symbolic-link-preserving-tar/settings.gradle'
-  - 'buildSrc/src/testKit/testingConventions/empty_test_task/.gitignore'
-  - 'client/rest-high-level/src/main/resources/META-INF/services/org.opensearch.plugins.spi.NamedXContentProvider'
-  - 'distribution/bwc/bugfix/build.gradle'
-  - 'distribution/bwc/maintenance/build.gradle'
-  - 'distribution/bwc/minor/build.gradle'
-  - 'distribution/bwc/staged/build.gradle'
-  - 'libs/ssl-config/src/test/resources/certs/pem-utils/empty.pem'
-  - 'qa/evil-tests/src/test/resources/org/opensearch/common/logging/does_not_exist/nothing_to_see_here'
-  - 'qa/os/centos-6/build.gradle'
-  - 'qa/os/debian-8/build.gradle'
-  - 'qa/os/oel-6/build.gradle'
-  - 'qa/os/oel-7/build.gradle'
-  - 'qa/os/sles-12/build.gradle'
-  # Test requires no new line for these files
-  - 'server/src/test/resources/org/opensearch/action/bulk/simple-bulk11.json'
-  - 'server/src/test/resources/org/opensearch/action/search/simple-msearch5.json'
-
-rules:
-  # checks if file ends in a newline character
-  end-of-file:
-    # set to true to enable this rule
-    enable: true
-
-    # if true also checks if file ends in a single newline character
-    single-new-line: true
diff --git a/CHANGELOG.md b/CHANGELOG.md
index dbf65f07083fb..1cdf2f118d242 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,8 +7,26 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 ### Added
 - Add GeoTile and GeoHash Grid aggregations on GeoShapes. ([#5589](https://github.com/opensearch-project/OpenSearch/pull/5589))
 - Disallow multiple data paths for search nodes ([#6427](https://github.com/opensearch-project/OpenSearch/pull/6427))
+- [Segment Replication] Allocation and rebalancing based on average primary shard count per index ([#6422](https://github.com/opensearch-project/OpenSearch/pull/6422))
+- The truncation limit of the OpenSearchJsonLayout logger is now configurable ([#6569](https://github.com/opensearch-project/OpenSearch/pull/6569))
+- Add 'base_path' setting to File System Repository ([#6558](https://github.com/opensearch-project/OpenSearch/pull/6558))
+- Return success on DeletePits when no PITs exist. ([#6544](https://github.com/opensearch-project/OpenSearch/pull/6544))
+- Add node repurpose command for search nodes ([#6517](https://github.com/opensearch-project/OpenSearch/pull/6517))
+- [Segment Replication] Apply backpressure when replicas fall behind ([#6563](https://github.com/opensearch-project/OpenSearch/pull/6563))
 
 ### Dependencies
+- Bump `org.apache.logging.log4j:log4j-core` from 2.18.0 to 2.20.0 ([#6490](https://github.com/opensearch-project/OpenSearch/pull/6490))
+- Bump `com.azure:azure-storage-common` from 12.19.3 to 12.20.0 ([#6492](https://github.com/opensearch-project/OpenSearch/pull/6492)
+- Bump `snakeyaml` from 1.33 to 2.0 ([#6511](https://github.com/opensearch-project/OpenSearch/pull/6511))
+- Bump `io.projectreactor.netty:reactor-netty` from 1.1.3 to 1.1.4
+- Bump `com.avast.gradle:gradle-docker-compose-plugin` from 0.15.2 to 0.16.11
+- Bump `net.minidev:json-smart` from 2.4.8 to 2.4.9
+- Bump `com.google.protobuf:protobuf-java` from 3.22.0 to 3.22.2
+- Bump Netty to 4.1.90.Final ([#6677](https://github.com/opensearch-project/OpenSearch/pull/6677)
+- Bump `com.diffplug.spotless` from 6.15.0 to 6.17.0
+- Bump `org.apache.zookeeper:zookeeper` from 3.8.0 to 3.8.1
+- Bump `net.minidev:json-smart` from 2.4.7 to 2.4.10
+- Bump `org.apache.maven:maven-model` from 3.6.2 to 3.9.1
 
 ### Changed
 - Require MediaType in Strings.toString API ([#6009](https://github.com/opensearch-project/OpenSearch/pull/6009))
@@ -16,11 +34,17 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Introduce a new field type: flat_object ([#6507](https://github.com/opensearch-project/OpenSearch/pull/6507))
 
 ### Deprecated
+- Map, List, and Set in org.opensearch.common.collect ([#6609](https://github.com/opensearch-project/OpenSearch/pull/6609))
 
 ### Removed
 
 ### Fixed
+- Added depth check in doc parser for deep nested document ([#5199](https://github.com/opensearch-project/OpenSearch/pull/5199))
+- Added equals/hashcode for named DocValueFormat.DateTime inner class ([#6357](https://github.com/opensearch-project/OpenSearch/pull/6357))
+- Fixed bug for searchable snapshot to take 'base_path' of blob into account ([#6558](https://github.com/opensearch-project/OpenSearch/pull/6558))
+- Fix fuzziness validation ([#5805](https://github.com/opensearch-project/OpenSearch/pull/5805))
 
 ### Security
 
+[Unreleased 3.0]: https://github.com/opensearch-project/OpenSearch/compare/2.x...HEAD
 [Unreleased 2.x]: https://github.com/opensearch-project/OpenSearch/compare/2.5...2.x
diff --git a/benchmarks/src/main/java/org/opensearch/benchmark/search/aggregations/bucket/terms/StringTermsSerializationBenchmark.java b/benchmarks/src/main/java/org/opensearch/benchmark/search/aggregations/bucket/terms/StringTermsSerializationBenchmark.java
index 6d8721ce64090..e49ae187acea7 100644
--- a/benchmarks/src/main/java/org/opensearch/benchmark/search/aggregations/bucket/terms/StringTermsSerializationBenchmark.java
+++ b/benchmarks/src/main/java/org/opensearch/benchmark/search/aggregations/bucket/terms/StringTermsSerializationBenchmark.java
@@ -64,9 +64,7 @@
 @State(Scope.Benchmark)
 public class StringTermsSerializationBenchmark {
     private static final NamedWriteableRegistry REGISTRY = new NamedWriteableRegistry(
-        org.opensearch.common.collect.List.of(
-            new NamedWriteableRegistry.Entry(InternalAggregation.class, StringTerms.NAME, StringTerms::new)
-        )
+        List.of(new NamedWriteableRegistry.Entry(InternalAggregation.class, StringTerms.NAME, StringTerms::new))
     );
     @Param(value = { "1000" })
     private int buckets;
@@ -75,15 +73,13 @@ public class StringTermsSerializationBenchmark {
 
     @Setup
     public void initResults() {
-        results = DelayableWriteable.referencing(InternalAggregations.from(org.opensearch.common.collect.List.of(newTerms(true))));
+        results = DelayableWriteable.referencing(InternalAggregations.from(List.of(newTerms(true))));
     }
 
     private StringTerms newTerms(boolean withNested) {
         List<StringTerms.Bucket> resultBuckets = new ArrayList<>(buckets);
         for (int i = 0; i < buckets; i++) {
-            InternalAggregations inner = withNested
-                ? InternalAggregations.from(org.opensearch.common.collect.List.of(newTerms(false)))
-                : InternalAggregations.EMPTY;
+            InternalAggregations inner = withNested ? InternalAggregations.from(List.of(newTerms(false))) : InternalAggregations.EMPTY;
             resultBuckets.add(new StringTerms.Bucket(new BytesRef("test" + i), i, inner, false, 0, DocValueFormat.RAW));
         }
         return new StringTerms(
diff --git a/build.gradle b/build.gradle
index 4f432bc100678..be733233f60b5 100644
--- a/build.gradle
+++ b/build.gradle
@@ -45,7 +45,6 @@ import org.gradle.plugins.ide.eclipse.model.AccessRule
 import org.gradle.plugins.ide.eclipse.model.EclipseJdt
 import org.gradle.plugins.ide.eclipse.model.SourceFolder
 import org.gradle.api.Project;
-import org.gradle.api.internal.tasks.testing.junit.JUnitTestFramework
 import org.gradle.process.ExecResult;
 
 import static org.opensearch.gradle.util.GradleUtils.maybeConfigure
@@ -54,7 +53,7 @@ plugins {
   id 'lifecycle-base'
   id 'opensearch.docker-support'
   id 'opensearch.global-build-info'
-  id "com.diffplug.spotless" version "6.15.0" apply false
+  id "com.diffplug.spotless" version "6.17.0" apply false
   id "org.gradle.test-retry" version "1.5.1" apply false
   id "test-report-aggregation"
   id 'jacoco-report-aggregation'
@@ -76,19 +75,6 @@ allprojects {
   group = 'org.opensearch'
   version = VersionProperties.getOpenSearch()
   description = "OpenSearch subproject ${project.path}"
-
-  afterEvaluate {
-    project.tasks.withType(Test) { task ->
-      // This is so hacky: now, by default, test tasks uses JUnit framework and always includes 'junit'
-      // JARs from the Gradle distribution (no ways to override this behavior). It causes JAR hell on test 
-      // classpath, example of the report:
-      //
-      //  jar1: /home/ubuntu/.gradle/caches/modules-2/files-2.1/junit/junit/4.13.2/8ac9e16d933b6fb43bc7f576336b8f4d7eb5ba12/junit-4.13.2.jar
-      //  jar2: /home/ubuntu/.gradle/wrapper/dists/gradle-8.0-rc-1-all/2p8rgxxewg8l61n1p3vrzr9s8/gradle-8.0-rc-1/lib/junit-4.13.2.jar
-      // 
-      task.getTestFrameworkProperty().convention(getProviderFactory().provider(() -> new JUnitTestFramework(task, task.getFilter(), false)));
-    }
-  }
 }
 
 configure(allprojects - project(':distribution:archives:integ-test-zip')) {
diff --git a/buildSrc/build.gradle b/buildSrc/build.gradle
index aeeaf90f51c61..e6415d0a58f17 100644
--- a/buildSrc/build.gradle
+++ b/buildSrc/build.gradle
@@ -115,9 +115,9 @@ dependencies {
   api 'org.jdom:jdom2:2.0.6.1'
   api "org.jetbrains.kotlin:kotlin-stdlib-jdk8:${props.getProperty('kotlin')}"
   api 'de.thetaphi:forbiddenapis:3.4'
-  api 'com.avast.gradle:gradle-docker-compose-plugin:0.15.2'
+  api 'com.avast.gradle:gradle-docker-compose-plugin:0.16.11'
   api "org.yaml:snakeyaml:${props.getProperty('snakeyaml')}"
-  api 'org.apache.maven:maven-model:3.6.2'
+  api 'org.apache.maven:maven-model:3.9.1'
   api 'com.networknt:json-schema-validator:1.0.73'
   api "com.fasterxml.jackson.core:jackson-databind:${props.getProperty('jackson_databind')}"
 
diff --git a/buildSrc/src/main/java/org/opensearch/gradle/docker/DockerSupportPlugin.java b/buildSrc/src/main/java/org/opensearch/gradle/docker/DockerSupportPlugin.java
index 92777638982d2..5455875a96611 100644
--- a/buildSrc/src/main/java/org/opensearch/gradle/docker/DockerSupportPlugin.java
+++ b/buildSrc/src/main/java/org/opensearch/gradle/docker/DockerSupportPlugin.java
@@ -56,13 +56,9 @@ public void apply(Project project) {
 
         Provider<DockerSupportService> dockerSupportServiceProvider = project.getGradle()
             .getSharedServices()
-            .registerIfAbsent(
-                DOCKER_SUPPORT_SERVICE_NAME,
-                DockerSupportService.class,
-                spec -> spec.parameters(
-                    params -> { params.setExclusionsFile(new File(project.getRootDir(), DOCKER_ON_LINUX_EXCLUSIONS_FILE)); }
-                )
-            );
+            .registerIfAbsent(DOCKER_SUPPORT_SERVICE_NAME, DockerSupportService.class, spec -> spec.parameters(params -> {
+                params.setExclusionsFile(new File(project.getRootDir(), DOCKER_ON_LINUX_EXCLUSIONS_FILE));
+            }));
 
         // Ensure that if we are trying to run any DockerBuildTask tasks, we assert an available Docker installation exists
         project.getGradle().getTaskGraph().whenReady(graph -> {
diff --git a/buildSrc/src/main/java/org/opensearch/gradle/internal/InternalDistributionBwcSetupPlugin.java b/buildSrc/src/main/java/org/opensearch/gradle/internal/InternalDistributionBwcSetupPlugin.java
index dd2393702fe2b..33869e76680cd 100644
--- a/buildSrc/src/main/java/org/opensearch/gradle/internal/InternalDistributionBwcSetupPlugin.java
+++ b/buildSrc/src/main/java/org/opensearch/gradle/internal/InternalDistributionBwcSetupPlugin.java
@@ -76,12 +76,9 @@ public InternalDistributionBwcSetupPlugin(ProviderFactory providerFactory) {
     @Override
     public void apply(Project project) {
         project.getRootProject().getPluginManager().apply(GlobalBuildInfoPlugin.class);
-        BuildParams.getBwcVersions()
-            .forPreviousUnreleased(
-                (BwcVersions.UnreleasedVersionInfo unreleasedVersion) -> {
-                    configureBwcProject(project.project(unreleasedVersion.gradleProjectPath), unreleasedVersion);
-                }
-            );
+        BuildParams.getBwcVersions().forPreviousUnreleased((BwcVersions.UnreleasedVersionInfo unreleasedVersion) -> {
+            configureBwcProject(project.project(unreleasedVersion.gradleProjectPath), unreleasedVersion);
+        });
     }
 
     private void configureBwcProject(Project project, BwcVersions.UnreleasedVersionInfo versionInfo) {
diff --git a/buildSrc/src/main/java/org/opensearch/gradle/test/DistroTestPlugin.java b/buildSrc/src/main/java/org/opensearch/gradle/test/DistroTestPlugin.java
index 64e30700360b3..3bb92d826e5eb 100644
--- a/buildSrc/src/main/java/org/opensearch/gradle/test/DistroTestPlugin.java
+++ b/buildSrc/src/main/java/org/opensearch/gradle/test/DistroTestPlugin.java
@@ -197,13 +197,9 @@ public void apply(Project project) {
 
             // windows boxes get windows distributions, and linux boxes get linux distributions
             if (isWindows(vmProject)) {
-                configureVMWrapperTasks(
-                    vmProject,
-                    windowsTestTasks,
-                    depsTasks,
-                    wrapperTask -> { vmLifecyleTasks.get(OpenSearchDistribution.Type.ARCHIVE).configure(t -> t.dependsOn(wrapperTask)); },
-                    vmDependencies
-                );
+                configureVMWrapperTasks(vmProject, windowsTestTasks, depsTasks, wrapperTask -> {
+                    vmLifecyleTasks.get(OpenSearchDistribution.Type.ARCHIVE).configure(t -> t.dependsOn(wrapperTask));
+                }, vmDependencies);
             } else {
                 for (Entry<OpenSearchDistribution.Type, List<TaskProvider<Test>>> entry : linuxTestTasks.entrySet()) {
                     OpenSearchDistribution.Type type = entry.getKey();
diff --git a/buildSrc/src/testKit/thirdPartyAudit/sample_jars/build.gradle b/buildSrc/src/testKit/thirdPartyAudit/sample_jars/build.gradle
index 820c303a2e79f..b31e3b168c587 100644
--- a/buildSrc/src/testKit/thirdPartyAudit/sample_jars/build.gradle
+++ b/buildSrc/src/testKit/thirdPartyAudit/sample_jars/build.gradle
@@ -16,7 +16,7 @@ repositories {
   mavenCentral()
 }
 dependencies {
-  implementation 'org.apache.logging.log4j:log4j-core:2.18.0'
+  implementation 'org.apache.logging.log4j:log4j-core:2.20.0'
 }
 
 ["0.0.1", "0.0.2"].forEach { v ->
diff --git a/buildSrc/version.properties b/buildSrc/version.properties
index 4241255bcbf6f..7262080d06c61 100644
--- a/buildSrc/version.properties
+++ b/buildSrc/version.properties
@@ -9,7 +9,7 @@ spatial4j         = 0.7
 jts               = 1.15.0
 jackson           = 2.14.2
 jackson_databind  = 2.14.2
-snakeyaml         = 1.33
+snakeyaml         = 2.0
 icu4j             = 70.1
 supercsv          = 2.4.0
 # Update to 2.17.2+ is breaking OpenSearchJsonLayout (see https://issues.apache.org/jira/browse/LOG4J2-3562)
@@ -25,7 +25,7 @@ guava             = 31.1-jre
 # when updating the JNA version, also update the version in buildSrc/build.gradle
 jna               = 5.5.0
 
-netty             = 4.1.87.Final
+netty             = 4.1.90.Final
 joda              = 2.12.2
 
 # client dependencies
@@ -46,9 +46,9 @@ bouncycastle=1.70
 randomizedrunner  = 2.7.1
 junit             = 4.13.2
 hamcrest          = 2.1
-mockito           = 5.1.0
+mockito           = 5.2.0
 objenesis         = 3.2
-bytebuddy         = 1.12.22
+bytebuddy         = 1.14.2
 
 # benchmark dependencies
 jmh               = 1.35
diff --git a/client/rest-high-level/src/main/java/org/opensearch/client/core/MainResponse.java b/client/rest-high-level/src/main/java/org/opensearch/client/core/MainResponse.java
index b15ef2e699ca5..3f191885071a1 100644
--- a/client/rest-high-level/src/main/java/org/opensearch/client/core/MainResponse.java
+++ b/client/rest-high-level/src/main/java/org/opensearch/client/core/MainResponse.java
@@ -43,7 +43,9 @@ public class MainResponse {
     private static final ConstructingObjectParser<MainResponse, Void> PARSER = new ConstructingObjectParser<>(
         MainResponse.class.getName(),
         true,
-        args -> { return new MainResponse((String) args[0], (Version) args[1], (String) args[2], (String) args[3]); }
+        args -> {
+            return new MainResponse((String) args[0], (Version) args[1], (String) args[2], (String) args[3]);
+        }
     );
 
     static {
diff --git a/client/rest-high-level/src/main/java/org/opensearch/client/core/TermVectorsResponse.java b/client/rest-high-level/src/main/java/org/opensearch/client/core/TermVectorsResponse.java
index fa13abf72207e..9579b0eb90cb0 100644
--- a/client/rest-high-level/src/main/java/org/opensearch/client/core/TermVectorsResponse.java
+++ b/client/rest-high-level/src/main/java/org/opensearch/client/core/TermVectorsResponse.java
@@ -240,7 +240,9 @@ public static final class FieldStatistics {
             private static final ConstructingObjectParser<FieldStatistics, Void> PARSER = new ConstructingObjectParser<>(
                 "field_statistics",
                 true,
-                args -> { return new FieldStatistics((long) args[0], (int) args[1], (long) args[2]); }
+                args -> {
+                    return new FieldStatistics((long) args[0], (int) args[1], (long) args[2]);
+                }
             );
 
             static {
@@ -411,11 +413,9 @@ public int hashCode() {
 
         public static final class Token {
 
-            private static final ConstructingObjectParser<Token, Void> PARSER = new ConstructingObjectParser<>(
-                "token",
-                true,
-                args -> { return new Token((Integer) args[0], (Integer) args[1], (Integer) args[2], (String) args[3]); }
-            );
+            private static final ConstructingObjectParser<Token, Void> PARSER = new ConstructingObjectParser<>("token", true, args -> {
+                return new Token((Integer) args[0], (Integer) args[1], (Integer) args[2], (String) args[3]);
+            });
             static {
                 PARSER.declareInt(optionalConstructorArg(), new ParseField("start_offset"));
                 PARSER.declareInt(optionalConstructorArg(), new ParseField("end_offset"));
diff --git a/client/rest-high-level/src/test/java/org/opensearch/client/CrudIT.java b/client/rest-high-level/src/test/java/org/opensearch/client/CrudIT.java
index 999c2a0e7643b..ad7198195c0ee 100644
--- a/client/rest-high-level/src/test/java/org/opensearch/client/CrudIT.java
+++ b/client/rest-high-level/src/test/java/org/opensearch/client/CrudIT.java
@@ -628,10 +628,9 @@ public void testIndex() throws IOException {
             assertEquals("index", indexResponse.getIndex());
             assertEquals("with_create_op_type", indexResponse.getId());
 
-            OpenSearchStatusException exception = expectThrows(
-                OpenSearchStatusException.class,
-                () -> { execute(indexRequest, highLevelClient()::index, highLevelClient()::indexAsync); }
-            );
+            OpenSearchStatusException exception = expectThrows(OpenSearchStatusException.class, () -> {
+                execute(indexRequest, highLevelClient()::index, highLevelClient()::indexAsync);
+            });
 
             assertEquals(RestStatus.CONFLICT, exception.status());
             assertEquals(
diff --git a/client/rest-high-level/src/test/java/org/opensearch/client/IndicesClientIT.java b/client/rest-high-level/src/test/java/org/opensearch/client/IndicesClientIT.java
index f9c8851f8839e..9cdf5beb71906 100644
--- a/client/rest-high-level/src/test/java/org/opensearch/client/IndicesClientIT.java
+++ b/client/rest-high-level/src/test/java/org/opensearch/client/IndicesClientIT.java
@@ -2032,8 +2032,8 @@ public void testSimulateIndexTemplate() throws Exception {
         Settings settings = Settings.builder().put("index.number_of_shards", 1).build();
         CompressedXContent mappings = new CompressedXContent("{\"properties\":{\"host_name\":{\"type\":\"keyword\"}}}");
         AliasMetadata alias = AliasMetadata.builder("alias").writeIndex(true).build();
-        Template template = new Template(settings, mappings, org.opensearch.common.collect.Map.of("alias", alias));
-        List<String> pattern = org.opensearch.common.collect.List.of("pattern");
+        Template template = new Template(settings, mappings, Map.of("alias", alias));
+        List<String> pattern = List.of("pattern");
         ComposableIndexTemplate indexTemplate = new ComposableIndexTemplate(
             pattern,
             template,
@@ -2058,7 +2058,7 @@ public void testSimulateIndexTemplate() throws Exception {
         AliasMetadata simulationAlias = AliasMetadata.builder("simulation-alias").writeIndex(true).build();
         ComposableIndexTemplate simulationTemplate = new ComposableIndexTemplate(
             pattern,
-            new Template(null, null, org.opensearch.common.collect.Map.of("simulation-alias", simulationAlias)),
+            new Template(null, null, Map.of("simulation-alias", simulationAlias)),
             Collections.emptyList(),
             2L,
             1L,
diff --git a/client/rest-high-level/src/test/java/org/opensearch/client/ReindexIT.java b/client/rest-high-level/src/test/java/org/opensearch/client/ReindexIT.java
index 78fb2aef02ee0..cbee86c34c360 100644
--- a/client/rest-high-level/src/test/java/org/opensearch/client/ReindexIT.java
+++ b/client/rest-high-level/src/test/java/org/opensearch/client/ReindexIT.java
@@ -112,10 +112,9 @@ public void testReindex() throws IOException {
             reindexRequest.setRefresh(true);
             reindexRequest.setRequireAlias(true);
 
-            OpenSearchStatusException exception = expectThrows(
-                OpenSearchStatusException.class,
-                () -> { execute(reindexRequest, highLevelClient()::reindex, highLevelClient()::reindexAsync); }
-            );
+            OpenSearchStatusException exception = expectThrows(OpenSearchStatusException.class, () -> {
+                execute(reindexRequest, highLevelClient()::reindex, highLevelClient()::reindexAsync);
+            });
             assertEquals(RestStatus.NOT_FOUND, exception.status());
             assertEquals(
                 "OpenSearch exception [type=index_not_found_exception, reason=no such index [dest] and [require_alias] request flag is [true] and [dest] is not an alias]",
diff --git a/client/rest-high-level/src/test/java/org/opensearch/client/RestHighLevelClientTests.java b/client/rest-high-level/src/test/java/org/opensearch/client/RestHighLevelClientTests.java
index a50cc811a87dc..9d1b83a32fb02 100644
--- a/client/rest-high-level/src/test/java/org/opensearch/client/RestHighLevelClientTests.java
+++ b/client/rest-high-level/src/test/java/org/opensearch/client/RestHighLevelClientTests.java
@@ -427,13 +427,9 @@ public void testPerformRequestOnSuccess() throws IOException {
         {
             IOException ioe = expectThrows(
                 IOException.class,
-                () -> restHighLevelClient.performRequest(
-                    mainRequest,
-                    requestConverter,
-                    RequestOptions.DEFAULT,
-                    response -> { throw new IllegalStateException(); },
-                    Collections.emptySet()
-                )
+                () -> restHighLevelClient.performRequest(mainRequest, requestConverter, RequestOptions.DEFAULT, response -> {
+                    throw new IllegalStateException();
+                }, Collections.emptySet())
             );
             assertEquals(
                 "Unable to parse response body for Response{requestLine=GET / http/1.1, host=http://localhost:9200, "
@@ -575,13 +571,9 @@ public void testPerformRequestOnResponseExceptionWithIgnoresErrorNoBody() throws
         when(restClient.performRequest(any(Request.class))).thenThrow(responseException);
         OpenSearchException openSearchException = expectThrows(
             OpenSearchException.class,
-            () -> restHighLevelClient.performRequest(
-                mainRequest,
-                requestConverter,
-                RequestOptions.DEFAULT,
-                response -> { throw new IllegalStateException(); },
-                Collections.singleton(404)
-            )
+            () -> restHighLevelClient.performRequest(mainRequest, requestConverter, RequestOptions.DEFAULT, response -> {
+                throw new IllegalStateException();
+            }, Collections.singleton(404))
         );
         assertEquals(RestStatus.NOT_FOUND, openSearchException.status());
         assertSame(responseException, openSearchException.getCause());
@@ -598,13 +590,9 @@ public void testPerformRequestOnResponseExceptionWithIgnoresErrorValidBody() thr
         when(restClient.performRequest(any(Request.class))).thenThrow(responseException);
         OpenSearchException openSearchException = expectThrows(
             OpenSearchException.class,
-            () -> restHighLevelClient.performRequest(
-                mainRequest,
-                requestConverter,
-                RequestOptions.DEFAULT,
-                response -> { throw new IllegalStateException(); },
-                Collections.singleton(404)
-            )
+            () -> restHighLevelClient.performRequest(mainRequest, requestConverter, RequestOptions.DEFAULT, response -> {
+                throw new IllegalStateException();
+            }, Collections.singleton(404))
         );
         assertEquals(RestStatus.NOT_FOUND, openSearchException.status());
         assertSame(responseException, openSearchException.getSuppressed()[0]);
diff --git a/gradle/formatting.gradle b/gradle/formatting.gradle
index e0939fa9766f2..9066a122b71b2 100644
--- a/gradle/formatting.gradle
+++ b/gradle/formatting.gradle
@@ -68,6 +68,7 @@ allprojects {
           removeUnusedImports()
           eclipse().configFile rootProject.file('buildSrc/formatterConfig.xml')
           trimTrailingWhitespace()
+          endWithNewline()
 
           custom 'Refuse wildcard imports', {
                 // Wildcard imports can't be resolved; fail the build
@@ -81,6 +82,12 @@ allprojects {
             paddedCell()
           }
         }
+        format 'misc', {
+            target '*.md', '*.gradle', '**/*.yaml', '**/*.yml', '**/*.svg'   
+
+            trimTrailingWhitespace()
+            endWithNewline()
+        }
       }
 
       precommit.dependsOn 'spotlessJavaCheck'
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 967dd3ccea2d7..21b7e71e15d65 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -11,7 +11,7 @@
 
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.0.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.0.2-all.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionSha256Sum=948d1e4ccc2f6ae36cbfa087d827aaca51403acae5411e664a6000bb47946f22
+distributionSha256Sum=47a5bfed9ef814f90f8debcbbb315e8e7c654109acd224595ea39fca95c5d4da
diff --git a/libs/common/src/main/java/org/opensearch/common/collect/List.java b/libs/common/src/main/java/org/opensearch/common/collect/List.java
index c28a69a515d35..07cfc2c019856 100644
--- a/libs/common/src/main/java/org/opensearch/common/collect/List.java
+++ b/libs/common/src/main/java/org/opensearch/common/collect/List.java
@@ -37,10 +37,10 @@
 /**
  * Java 9 List
  *
- * todo: deprecate and remove w/ min jdk upgrade to 11?
  *
  * @opensearch.internal
  */
+@Deprecated(forRemoval = true)
 public class List {
 
     /**
diff --git a/libs/common/src/main/java/org/opensearch/common/collect/Map.java b/libs/common/src/main/java/org/opensearch/common/collect/Map.java
index a0b8c03d3d3e4..3913c0fd942a4 100644
--- a/libs/common/src/main/java/org/opensearch/common/collect/Map.java
+++ b/libs/common/src/main/java/org/opensearch/common/collect/Map.java
@@ -35,10 +35,10 @@
 /**
  * Java 9 Map
  *
- * todo: deprecate and remove w/ min jdk upgrade to 11?
  *
  * @opensearch.internal
  */
+@Deprecated(forRemoval = true)
 public class Map {
 
     /**
diff --git a/libs/common/src/main/java/org/opensearch/common/collect/Set.java b/libs/common/src/main/java/org/opensearch/common/collect/Set.java
index 11d59cead6009..0c3899b2aaacd 100644
--- a/libs/common/src/main/java/org/opensearch/common/collect/Set.java
+++ b/libs/common/src/main/java/org/opensearch/common/collect/Set.java
@@ -37,10 +37,10 @@
 /**
  * Java 9 Set
  *
- * todo: deprecate and remove w/ min jdk upgrade to 11?
  *
  * @opensearch.internal
  */
+@Deprecated(forRemoval = true)
 public class Set {
 
     /**
diff --git a/libs/common/src/test/java/org/opensearch/common/collect/ListTests.java b/libs/common/src/test/java/org/opensearch/common/collect/ListTests.java
deleted file mode 100644
index 70841a102b783..0000000000000
--- a/libs/common/src/test/java/org/opensearch/common/collect/ListTests.java
+++ /dev/null
@@ -1,83 +0,0 @@
-/*
- * SPDX-License-Identifier: Apache-2.0
- *
- * The OpenSearch Contributors require contributions made to
- * this file be licensed under the Apache-2.0 license or a
- * compatible open source license.
- */
-
-/*
- * Licensed to Elasticsearch under one or more contributor
- * license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright
- * ownership. Elasticsearch licenses this file to you under
- * the Apache License, Version 2.0 (the "License"); you may
- * not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-
-/*
- * Modifications Copyright OpenSearch Contributors. See
- * GitHub history for details.
- */
-
-package org.opensearch.common.collect;
-
-import org.opensearch.test.OpenSearchTestCase;
-
-import java.util.Arrays;
-import java.util.Collection;
-
-import static org.hamcrest.CoreMatchers.equalTo;
-
-public class ListTests extends OpenSearchTestCase {
-
-    public void testStringListOfZero() {
-        final String[] strings = {};
-        final java.util.List<String> stringsList = List.of(strings);
-        assertThat(stringsList.size(), equalTo(strings.length));
-        assertTrue(stringsList.containsAll(Arrays.asList(strings)));
-        expectThrows(UnsupportedOperationException.class, () -> stringsList.add("foo"));
-    }
-
-    public void testStringListOfOne() {
-        final String[] strings = { "foo" };
-        final java.util.List<String> stringsList = List.of(strings);
-        assertThat(stringsList.size(), equalTo(strings.length));
-        assertTrue(stringsList.containsAll(Arrays.asList(strings)));
-        expectThrows(UnsupportedOperationException.class, () -> stringsList.add("foo"));
-    }
-
-    public void testStringListOfTwo() {
-        final String[] strings = { "foo", "bar" };
-        final java.util.List<String> stringsList = List.of(strings);
-        assertThat(stringsList.size(), equalTo(strings.length));
-        assertTrue(stringsList.containsAll(Arrays.asList(strings)));
-        expectThrows(UnsupportedOperationException.class, () -> stringsList.add("foo"));
-    }
-
-    public void testStringListOfN() {
-        final String[] strings = { "foo", "bar", "baz" };
-        final java.util.List<String> stringsList = List.of(strings);
-        assertThat(stringsList.size(), equalTo(strings.length));
-        assertTrue(stringsList.containsAll(Arrays.asList(strings)));
-        expectThrows(UnsupportedOperationException.class, () -> stringsList.add("foo"));
-    }
-
-    public void testCopyOf() {
-        final Collection<String> coll = Arrays.asList("foo", "bar", "baz");
-        final java.util.List<String> copy = List.copyOf(coll);
-        assertThat(coll.size(), equalTo(copy.size()));
-        assertTrue(copy.containsAll(coll));
-        expectThrows(UnsupportedOperationException.class, () -> copy.add("foo"));
-    }
-}
diff --git a/libs/common/src/test/java/org/opensearch/common/collect/MapTests.java b/libs/common/src/test/java/org/opensearch/common/collect/MapTests.java
deleted file mode 100644
index 8d7ffa71df562..0000000000000
--- a/libs/common/src/test/java/org/opensearch/common/collect/MapTests.java
+++ /dev/null
@@ -1,210 +0,0 @@
-/*
- * SPDX-License-Identifier: Apache-2.0
- *
- * The OpenSearch Contributors require contributions made to
- * this file be licensed under the Apache-2.0 license or a
- * compatible open source license.
- */
-
-/*
- * Licensed to Elasticsearch under one or more contributor
- * license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright
- * ownership. Elasticsearch licenses this file to you under
- * the Apache License, Version 2.0 (the "License"); you may
- * not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-
-/*
- * Modifications Copyright OpenSearch Contributors. See
- * GitHub history for details.
- */
-
-package org.opensearch.common.collect;
-
-import org.opensearch.test.OpenSearchTestCase;
-
-import static org.hamcrest.CoreMatchers.equalTo;
-
-public class MapTests extends OpenSearchTestCase {
-
-    private static final String[] numbers = { "zero", "one", "two", "three", "four", "five", "six", "seven", "eight", "nine" };
-
-    public void testMapOfZero() {
-        final java.util.Map<String, Integer> map = Map.of();
-        validateMapContents(map, 0);
-    }
-
-    public void testMapOfOne() {
-        final java.util.Map<String, Integer> map = Map.of(numbers[0], 0);
-        validateMapContents(map, 1);
-    }
-
-    public void testMapOfTwo() {
-        final java.util.Map<String, Integer> map = Map.of(numbers[0], 0, numbers[1], 1);
-        validateMapContents(map, 2);
-    }
-
-    public void testMapOfThree() {
-        final java.util.Map<String, Integer> map = Map.of(numbers[0], 0, numbers[1], 1, numbers[2], 2);
-        validateMapContents(map, 3);
-    }
-
-    public void testMapOfFour() {
-        final java.util.Map<String, Integer> map = Map.of(numbers[0], 0, numbers[1], 1, numbers[2], 2, numbers[3], 3);
-        validateMapContents(map, 4);
-    }
-
-    public void testMapOfFive() {
-        final java.util.Map<String, Integer> map = Map.of(numbers[0], 0, numbers[1], 1, numbers[2], 2, numbers[3], 3, numbers[4], 4);
-        validateMapContents(map, 5);
-    }
-
-    public void testMapOfSix() {
-        final java.util.Map<String, Integer> map = Map.of(
-            numbers[0],
-            0,
-            numbers[1],
-            1,
-            numbers[2],
-            2,
-            numbers[3],
-            3,
-            numbers[4],
-            4,
-            numbers[5],
-            5
-        );
-        validateMapContents(map, 6);
-    }
-
-    public void testMapOfSeven() {
-        final java.util.Map<String, Integer> map = Map.of(
-            numbers[0],
-            0,
-            numbers[1],
-            1,
-            numbers[2],
-            2,
-            numbers[3],
-            3,
-            numbers[4],
-            4,
-            numbers[5],
-            5,
-            numbers[6],
-            6
-        );
-        validateMapContents(map, 7);
-    }
-
-    public void testMapOfEight() {
-        final java.util.Map<String, Integer> map = Map.of(
-            numbers[0],
-            0,
-            numbers[1],
-            1,
-            numbers[2],
-            2,
-            numbers[3],
-            3,
-            numbers[4],
-            4,
-            numbers[5],
-            5,
-            numbers[6],
-            6,
-            numbers[7],
-            7
-        );
-        validateMapContents(map, 8);
-    }
-
-    public void testMapOfNine() {
-        final java.util.Map<String, Integer> map = Map.of(
-            numbers[0],
-            0,
-            numbers[1],
-            1,
-            numbers[2],
-            2,
-            numbers[3],
-            3,
-            numbers[4],
-            4,
-            numbers[5],
-            5,
-            numbers[6],
-            6,
-            numbers[7],
-            7,
-            numbers[8],
-            8
-        );
-        validateMapContents(map, 9);
-    }
-
-    public void testMapOfTen() {
-        final java.util.Map<String, Integer> map = Map.of(
-            numbers[0],
-            0,
-            numbers[1],
-            1,
-            numbers[2],
-            2,
-            numbers[3],
-            3,
-            numbers[4],
-            4,
-            numbers[5],
-            5,
-            numbers[6],
-            6,
-            numbers[7],
-            7,
-            numbers[8],
-            8,
-            numbers[9],
-            9
-        );
-        validateMapContents(map, 10);
-    }
-
-    private static void validateMapContents(java.util.Map<String, Integer> map, int size) {
-        assertThat(map.size(), equalTo(size));
-        for (int k = 0; k < map.size(); k++) {
-            assertEquals(Integer.class, map.get(numbers[k]).getClass());
-            assertThat(k, equalTo(map.get(numbers[k])));
-        }
-        expectThrows(UnsupportedOperationException.class, () -> map.put("foo", 42));
-    }
-
-    public void testOfEntries() {
-        final java.util.Map<String, Integer> map = Map.ofEntries(
-            Map.entry(numbers[0], 0),
-            Map.entry(numbers[1], 1),
-            Map.entry(numbers[2], 2)
-        );
-        validateMapContents(map, 3);
-    }
-
-    public void testCopyOf() {
-        final java.util.Map<String, String> map1 = Map.of("fooK", "fooV", "barK", "barV", "bazK", "bazV");
-        final java.util.Map<String, String> copy = Map.copyOf(map1);
-        assertThat(map1.size(), equalTo(copy.size()));
-        for (java.util.Map.Entry<String, String> entry : map1.entrySet()) {
-            assertEquals(entry.getValue(), copy.get(entry.getKey()));
-        }
-        expectThrows(UnsupportedOperationException.class, () -> copy.put("foo", "bar"));
-    }
-}
diff --git a/libs/common/src/test/java/org/opensearch/common/collect/SetTests.java b/libs/common/src/test/java/org/opensearch/common/collect/SetTests.java
deleted file mode 100644
index 1b7f29ff0d6f1..0000000000000
--- a/libs/common/src/test/java/org/opensearch/common/collect/SetTests.java
+++ /dev/null
@@ -1,83 +0,0 @@
-/*
- * SPDX-License-Identifier: Apache-2.0
- *
- * The OpenSearch Contributors require contributions made to
- * this file be licensed under the Apache-2.0 license or a
- * compatible open source license.
- */
-
-/*
- * Licensed to Elasticsearch under one or more contributor
- * license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright
- * ownership. Elasticsearch licenses this file to you under
- * the Apache License, Version 2.0 (the "License"); you may
- * not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-
-/*
- * Modifications Copyright OpenSearch Contributors. See
- * GitHub history for details.
- */
-
-package org.opensearch.common.collect;
-
-import org.opensearch.test.OpenSearchTestCase;
-
-import java.util.Arrays;
-import java.util.Collection;
-
-import static org.hamcrest.CoreMatchers.equalTo;
-
-public class SetTests extends OpenSearchTestCase {
-
-    public void testStringSetOfZero() {
-        final String[] strings = {};
-        final java.util.Set<String> stringsSet = Set.of(strings);
-        assertThat(stringsSet.size(), equalTo(strings.length));
-        assertTrue(stringsSet.containsAll(Arrays.asList(strings)));
-        expectThrows(UnsupportedOperationException.class, () -> stringsSet.add("foo"));
-    }
-
-    public void testStringSetOfOne() {
-        final String[] strings = { "foo" };
-        final java.util.Set<String> stringsSet = Set.of(strings);
-        assertThat(stringsSet.size(), equalTo(strings.length));
-        assertTrue(stringsSet.containsAll(Arrays.asList(strings)));
-        expectThrows(UnsupportedOperationException.class, () -> stringsSet.add("foo"));
-    }
-
-    public void testStringSetOfTwo() {
-        final String[] strings = { "foo", "bar" };
-        final java.util.Set<String> stringsSet = Set.of(strings);
-        assertThat(stringsSet.size(), equalTo(strings.length));
-        assertTrue(stringsSet.containsAll(Arrays.asList(strings)));
-        expectThrows(UnsupportedOperationException.class, () -> stringsSet.add("foo"));
-    }
-
-    public void testStringSetOfN() {
-        final String[] strings = { "foo", "bar", "baz" };
-        final java.util.Set<String> stringsSet = Set.of(strings);
-        assertThat(stringsSet.size(), equalTo(strings.length));
-        assertTrue(stringsSet.containsAll(Arrays.asList(strings)));
-        expectThrows(UnsupportedOperationException.class, () -> stringsSet.add("foo"));
-    }
-
-    public void testCopyOf() {
-        final Collection<String> coll = Arrays.asList("foo", "bar", "baz");
-        final java.util.Set<String> copy = Set.copyOf(coll);
-        assertThat(coll.size(), equalTo(copy.size()));
-        assertTrue(copy.containsAll(coll));
-        expectThrows(UnsupportedOperationException.class, () -> copy.add("foo"));
-    }
-}
diff --git a/libs/grok/src/test/java/org/opensearch/grok/GrokTests.java b/libs/grok/src/test/java/org/opensearch/grok/GrokTests.java
index ed48585cc124a..bdcde57f91bb3 100644
--- a/libs/grok/src/test/java/org/opensearch/grok/GrokTests.java
+++ b/libs/grok/src/test/java/org/opensearch/grok/GrokTests.java
@@ -65,20 +65,20 @@
 public class GrokTests extends OpenSearchTestCase {
     public void testMatchWithoutCaptures() {
         Grok grok = new Grok(Grok.BUILTIN_PATTERNS, "value", logger::warn);
-        assertThat(grok.captures("value"), equalTo(org.opensearch.common.collect.Map.of()));
-        assertThat(grok.captures("prefix_value"), equalTo(org.opensearch.common.collect.Map.of()));
+        assertThat(grok.captures("value"), equalTo(Map.of()));
+        assertThat(grok.captures("prefix_value"), equalTo(Map.of()));
         assertThat(grok.captures("no_match"), nullValue());
     }
 
     public void testCaputuresBytes() {
         Grok grok = new Grok(Grok.BUILTIN_PATTERNS, "%{NUMBER:n:int}", logger::warn);
         byte[] utf8 = "10".getBytes(StandardCharsets.UTF_8);
-        assertThat(captureBytes(grok, utf8, 0, utf8.length), equalTo(org.opensearch.common.collect.Map.of("n", 10)));
-        assertThat(captureBytes(grok, utf8, 0, 1), equalTo(org.opensearch.common.collect.Map.of("n", 1)));
+        assertThat(captureBytes(grok, utf8, 0, utf8.length), equalTo(Map.of("n", 10)));
+        assertThat(captureBytes(grok, utf8, 0, 1), equalTo(Map.of("n", 1)));
         utf8 = "10 11 12".getBytes(StandardCharsets.UTF_8);
-        assertThat(captureBytes(grok, utf8, 0, 2), equalTo(org.opensearch.common.collect.Map.of("n", 10)));
-        assertThat(captureBytes(grok, utf8, 3, 2), equalTo(org.opensearch.common.collect.Map.of("n", 11)));
-        assertThat(captureBytes(grok, utf8, 6, 2), equalTo(org.opensearch.common.collect.Map.of("n", 12)));
+        assertThat(captureBytes(grok, utf8, 0, 2), equalTo(Map.of("n", 10)));
+        assertThat(captureBytes(grok, utf8, 3, 2), equalTo(Map.of("n", 11)));
+        assertThat(captureBytes(grok, utf8, 6, 2), equalTo(Map.of("n", 12)));
     }
 
     private Map<String, Object> captureBytes(Grok grok, byte[] utf8, int offset, int length) {
@@ -99,15 +99,15 @@ public void testSimpleSyslogLine() {
         Grok grok = new Grok(Grok.BUILTIN_PATTERNS, "%{SYSLOGLINE}", logger::warn);
         assertCaptureConfig(
             grok,
-            org.opensearch.common.collect.Map.ofEntries(
-                org.opensearch.common.collect.Map.entry("facility", STRING),
-                org.opensearch.common.collect.Map.entry("logsource", STRING),
-                org.opensearch.common.collect.Map.entry("message", STRING),
-                org.opensearch.common.collect.Map.entry("pid", STRING),
-                org.opensearch.common.collect.Map.entry("priority", STRING),
-                org.opensearch.common.collect.Map.entry("program", STRING),
-                org.opensearch.common.collect.Map.entry("timestamp", STRING),
-                org.opensearch.common.collect.Map.entry("timestamp8601", STRING)
+            Map.ofEntries(
+                Map.entry("facility", STRING),
+                Map.entry("logsource", STRING),
+                Map.entry("message", STRING),
+                Map.entry("pid", STRING),
+                Map.entry("priority", STRING),
+                Map.entry("program", STRING),
+                Map.entry("timestamp", STRING),
+                Map.entry("timestamp8601", STRING)
             )
         );
         Map<String, Object> matches = grok.captures(line);
@@ -134,16 +134,16 @@ public void testSyslog5424Line() {
         Grok grok = new Grok(Grok.BUILTIN_PATTERNS, "%{SYSLOG5424LINE}", logger::warn);
         assertCaptureConfig(
             grok,
-            org.opensearch.common.collect.Map.ofEntries(
-                org.opensearch.common.collect.Map.entry("syslog5424_app", STRING),
-                org.opensearch.common.collect.Map.entry("syslog5424_host", STRING),
-                org.opensearch.common.collect.Map.entry("syslog5424_msg", STRING),
-                org.opensearch.common.collect.Map.entry("syslog5424_msgid", STRING),
-                org.opensearch.common.collect.Map.entry("syslog5424_pri", STRING),
-                org.opensearch.common.collect.Map.entry("syslog5424_proc", STRING),
-                org.opensearch.common.collect.Map.entry("syslog5424_sd", STRING),
-                org.opensearch.common.collect.Map.entry("syslog5424_ts", STRING),
-                org.opensearch.common.collect.Map.entry("syslog5424_ver", STRING)
+            Map.ofEntries(
+                Map.entry("syslog5424_app", STRING),
+                Map.entry("syslog5424_host", STRING),
+                Map.entry("syslog5424_msg", STRING),
+                Map.entry("syslog5424_msgid", STRING),
+                Map.entry("syslog5424_pri", STRING),
+                Map.entry("syslog5424_proc", STRING),
+                Map.entry("syslog5424_sd", STRING),
+                Map.entry("syslog5424_ts", STRING),
+                Map.entry("syslog5424_ver", STRING)
             )
         );
         Map<String, Object> matches = grok.captures(line);
@@ -161,14 +161,14 @@ public void testSyslog5424Line() {
     public void testDatePattern() {
         String line = "fancy 12-12-12 12:12:12";
         Grok grok = new Grok(Grok.BUILTIN_PATTERNS, "(?<timestamp>%{DATE_EU} %{TIME})", logger::warn);
-        assertCaptureConfig(grok, org.opensearch.common.collect.Map.of("timestamp", STRING));
+        assertCaptureConfig(grok, Map.of("timestamp", STRING));
         Map<String, Object> matches = grok.captures(line);
         assertEquals("12-12-12 12:12:12", matches.get("timestamp"));
     }
 
     public void testNilCoercedValues() {
         Grok grok = new Grok(Grok.BUILTIN_PATTERNS, "test (N/A|%{BASE10NUM:duration:float}ms)", logger::warn);
-        assertCaptureConfig(grok, org.opensearch.common.collect.Map.of("duration", FLOAT));
+        assertCaptureConfig(grok, Map.of("duration", FLOAT));
         Map<String, Object> matches = grok.captures("test 28.4ms");
         assertEquals(28.4f, matches.get("duration"));
         matches = grok.captures("test N/A");
@@ -177,7 +177,7 @@ public void testNilCoercedValues() {
 
     public void testNilWithNoCoercion() {
         Grok grok = new Grok(Grok.BUILTIN_PATTERNS, "test (N/A|%{BASE10NUM:duration}ms)", logger::warn);
-        assertCaptureConfig(grok, org.opensearch.common.collect.Map.of("duration", STRING));
+        assertCaptureConfig(grok, Map.of("duration", STRING));
         Map<String, Object> matches = grok.captures("test 28.4ms");
         assertEquals("28.4", matches.get("duration"));
         matches = grok.captures("test N/A");
@@ -194,13 +194,13 @@ public void testUnicodeSyslog() {
         );
         assertCaptureConfig(
             grok,
-            org.opensearch.common.collect.Map.ofEntries(
-                org.opensearch.common.collect.Map.entry("syslog_hostname", STRING),
-                org.opensearch.common.collect.Map.entry("syslog_message", STRING),
-                org.opensearch.common.collect.Map.entry("syslog_pid", STRING),
-                org.opensearch.common.collect.Map.entry("syslog_pri", STRING),
-                org.opensearch.common.collect.Map.entry("syslog_program", STRING),
-                org.opensearch.common.collect.Map.entry("syslog_timestamp", STRING)
+            Map.ofEntries(
+                Map.entry("syslog_hostname", STRING),
+                Map.entry("syslog_message", STRING),
+                Map.entry("syslog_pid", STRING),
+                Map.entry("syslog_pri", STRING),
+                Map.entry("syslog_program", STRING),
+                Map.entry("syslog_timestamp", STRING)
             )
         );
         Map<String, Object> matches = grok.captures(
@@ -215,21 +215,21 @@ public void testUnicodeSyslog() {
 
     public void testNamedFieldsWithWholeTextMatch() {
         Grok grok = new Grok(Grok.BUILTIN_PATTERNS, "%{DATE_EU:stimestamp}", logger::warn);
-        assertCaptureConfig(grok, org.opensearch.common.collect.Map.of("stimestamp", STRING));
+        assertCaptureConfig(grok, Map.of("stimestamp", STRING));
         Map<String, Object> matches = grok.captures("11/01/01");
         assertThat(matches.get("stimestamp"), equalTo("11/01/01"));
     }
 
     public void testWithOniguramaNamedCaptures() {
         Grok grok = new Grok(Grok.BUILTIN_PATTERNS, "(?<foo>\\w+)", logger::warn);
-        assertCaptureConfig(grok, org.opensearch.common.collect.Map.of("foo", STRING));
+        assertCaptureConfig(grok, Map.of("foo", STRING));
         Map<String, Object> matches = grok.captures("hello world");
         assertThat(matches.get("foo"), equalTo("hello"));
     }
 
     public void testISO8601() {
         Grok grok = new Grok(Grok.BUILTIN_PATTERNS, "^%{TIMESTAMP_ISO8601}$", logger::warn);
-        assertCaptureConfig(grok, org.opensearch.common.collect.Map.of());
+        assertCaptureConfig(grok, Map.of());
         List<String> timeMessages = Arrays.asList(
             "2001-01-01T00:00:00",
             "1974-03-02T04:09:09",
@@ -254,7 +254,7 @@ public void testISO8601() {
 
     public void testNotISO8601() {
         Grok grok = new Grok(Grok.BUILTIN_PATTERNS, "^%{TIMESTAMP_ISO8601}$", logger::warn);
-        assertCaptureConfig(grok, org.opensearch.common.collect.Map.of());
+        assertCaptureConfig(grok, Map.of());
         List<String> timeMessages = Arrays.asList(
             "2001-13-01T00:00:00", // invalid month
             "2001-00-01T00:00:00", // invalid month
@@ -294,7 +294,7 @@ public void testNoNamedCaptures() {
         String text = "wowza !!!Tal!!! - Tal";
         String pattern = "%{EXCITED_NAME} - %{NAME}";
         Grok g = new Grok(bank, pattern, false, logger::warn);
-        assertCaptureConfig(g, org.opensearch.common.collect.Map.of("EXCITED_NAME_0", STRING, "NAME_21", STRING, "NAME_22", STRING));
+        assertCaptureConfig(g, Map.of("EXCITED_NAME_0", STRING, "NAME_21", STRING, "NAME_22", STRING));
 
         assertEquals("(?<EXCITED_NAME_0>!!!(?<NAME_21>Tal)!!!) - (?<NAME_22>Tal)", g.toRegex(pattern));
         assertEquals(true, g.match(text));
@@ -400,7 +400,7 @@ public void testMalformedPattern() {
     public void testBooleanCaptures() {
         String pattern = "%{WORD:name}=%{WORD:status:boolean}";
         Grok g = new Grok(Grok.BUILTIN_PATTERNS, pattern, logger::warn);
-        assertCaptureConfig(g, org.opensearch.common.collect.Map.of("name", STRING, "status", BOOLEAN));
+        assertCaptureConfig(g, Map.of("name", STRING, "status", BOOLEAN));
 
         String text = "active=true";
         Map<String, Object> expected = new HashMap<>();
@@ -428,7 +428,7 @@ public void testNumericCaptures() {
 
         String pattern = "%{NUMBER:bytes:float} %{NUMBER:id:long} %{NUMBER:rating:double}";
         Grok g = new Grok(bank, pattern, logger::warn);
-        assertCaptureConfig(g, org.opensearch.common.collect.Map.of("bytes", FLOAT, "id", LONG, "rating", DOUBLE));
+        assertCaptureConfig(g, Map.of("bytes", FLOAT, "id", LONG, "rating", DOUBLE));
 
         String text = "12009.34 20000000000 4820.092";
         Map<String, Object> expected = new HashMap<>();
@@ -476,7 +476,7 @@ public void testNumericCapturesCoercion() {
 
         String pattern = "%{NUMBER:bytes:float} %{NUMBER:status} %{NUMBER}";
         Grok g = new Grok(bank, pattern, logger::warn);
-        assertCaptureConfig(g, org.opensearch.common.collect.Map.of("bytes", FLOAT, "status", STRING));
+        assertCaptureConfig(g, Map.of("bytes", FLOAT, "status", STRING));
 
         String text = "12009.34 200 9032";
         Map<String, Object> expected = new HashMap<>();
@@ -494,8 +494,8 @@ public void testGarbageTypeNameBecomesString() {
 
         String pattern = "%{NUMBER:f:not_a_valid_type}";
         Grok g = new Grok(bank, pattern, logger::warn);
-        assertCaptureConfig(g, org.opensearch.common.collect.Map.of("f", STRING));
-        assertThat(g.captures("12009.34"), equalTo(org.opensearch.common.collect.Map.of("f", "12009.34")));
+        assertCaptureConfig(g, Map.of("f", STRING));
+        assertThat(g.captures("12009.34"), equalTo(Map.of("f", "12009.34")));
     }
 
     public void testApacheLog() {
@@ -505,19 +505,19 @@ public void testApacheLog() {
         Grok grok = new Grok(Grok.BUILTIN_PATTERNS, "%{COMBINEDAPACHELOG}", logger::warn);
         assertCaptureConfig(
             grok,
-            org.opensearch.common.collect.Map.ofEntries(
-                org.opensearch.common.collect.Map.entry("agent", STRING),
-                org.opensearch.common.collect.Map.entry("auth", STRING),
-                org.opensearch.common.collect.Map.entry("bytes", STRING),
-                org.opensearch.common.collect.Map.entry("clientip", STRING),
-                org.opensearch.common.collect.Map.entry("httpversion", STRING),
-                org.opensearch.common.collect.Map.entry("ident", STRING),
-                org.opensearch.common.collect.Map.entry("rawrequest", STRING),
-                org.opensearch.common.collect.Map.entry("referrer", STRING),
-                org.opensearch.common.collect.Map.entry("request", STRING),
-                org.opensearch.common.collect.Map.entry("response", STRING),
-                org.opensearch.common.collect.Map.entry("timestamp", STRING),
-                org.opensearch.common.collect.Map.entry("verb", STRING)
+            Map.ofEntries(
+                Map.entry("agent", STRING),
+                Map.entry("auth", STRING),
+                Map.entry("bytes", STRING),
+                Map.entry("clientip", STRING),
+                Map.entry("httpversion", STRING),
+                Map.entry("ident", STRING),
+                Map.entry("rawrequest", STRING),
+                Map.entry("referrer", STRING),
+                Map.entry("request", STRING),
+                Map.entry("response", STRING),
+                Map.entry("timestamp", STRING),
+                Map.entry("verb", STRING)
             )
         );
         Map<String, Object> matches = grok.captures(logLine);
@@ -594,18 +594,18 @@ public void testComplete() {
         Grok grok = new Grok(bank, pattern, logger::warn);
         assertCaptureConfig(
             grok,
-            org.opensearch.common.collect.Map.ofEntries(
-                org.opensearch.common.collect.Map.entry("agent", STRING),
-                org.opensearch.common.collect.Map.entry("auth", STRING),
-                org.opensearch.common.collect.Map.entry("bytes", INTEGER),
-                org.opensearch.common.collect.Map.entry("clientip", STRING),
-                org.opensearch.common.collect.Map.entry("httpversion", STRING),
-                org.opensearch.common.collect.Map.entry("ident", STRING),
-                org.opensearch.common.collect.Map.entry("referrer", STRING),
-                org.opensearch.common.collect.Map.entry("request", STRING),
-                org.opensearch.common.collect.Map.entry("response", INTEGER),
-                org.opensearch.common.collect.Map.entry("timestamp", STRING),
-                org.opensearch.common.collect.Map.entry("verb", STRING)
+            Map.ofEntries(
+                Map.entry("agent", STRING),
+                Map.entry("auth", STRING),
+                Map.entry("bytes", INTEGER),
+                Map.entry("clientip", STRING),
+                Map.entry("httpversion", STRING),
+                Map.entry("ident", STRING),
+                Map.entry("referrer", STRING),
+                Map.entry("request", STRING),
+                Map.entry("response", INTEGER),
+                Map.entry("timestamp", STRING),
+                Map.entry("verb", STRING)
             )
         );
 
@@ -642,7 +642,7 @@ public void testMultipleNamedCapturesWithSameName() {
         Map<String, String> bank = new HashMap<>();
         bank.put("SINGLEDIGIT", "[0-9]");
         Grok grok = new Grok(bank, "%{SINGLEDIGIT:num}%{SINGLEDIGIT:num}", logger::warn);
-        assertCaptureConfig(grok, org.opensearch.common.collect.Map.of("num", STRING));
+        assertCaptureConfig(grok, Map.of("num", STRING));
 
         Map<String, Object> expected = new HashMap<>();
         expected.put("num", "1");
diff --git a/libs/x-content/licenses/snakeyaml-1.33.jar.sha1 b/libs/x-content/licenses/snakeyaml-1.33.jar.sha1
deleted file mode 100644
index c8a323290e7ba..0000000000000
--- a/libs/x-content/licenses/snakeyaml-1.33.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-2cd0a87ff7df953f810c344bdf2fe3340b954c69
\ No newline at end of file
diff --git a/libs/x-content/licenses/snakeyaml-2.0.jar.sha1 b/libs/x-content/licenses/snakeyaml-2.0.jar.sha1
new file mode 100644
index 0000000000000..d09dea5564729
--- /dev/null
+++ b/libs/x-content/licenses/snakeyaml-2.0.jar.sha1
@@ -0,0 +1 @@
+3aab2116756442bf0d4cd1c089b24d34c3baa253
\ No newline at end of file
diff --git a/modules/analysis-common/src/test/java/org/opensearch/analysis/common/SynonymsAnalysisTests.java b/modules/analysis-common/src/test/java/org/opensearch/analysis/common/SynonymsAnalysisTests.java
index 03404a284020b..e38599818d04f 100644
--- a/modules/analysis-common/src/test/java/org/opensearch/analysis/common/SynonymsAnalysisTests.java
+++ b/modules/analysis-common/src/test/java/org/opensearch/analysis/common/SynonymsAnalysisTests.java
@@ -244,10 +244,9 @@ public void testShingleFilters() {
             .build();
         IndexSettings idxSettings = IndexSettingsModule.newIndexSettings("index", settings);
 
-        expectThrows(
-            IllegalArgumentException.class,
-            () -> { indexAnalyzers = createTestAnalysis(idxSettings, settings, new CommonAnalysisPlugin()).indexAnalyzers; }
-        );
+        expectThrows(IllegalArgumentException.class, () -> {
+            indexAnalyzers = createTestAnalysis(idxSettings, settings, new CommonAnalysisPlugin()).indexAnalyzers;
+        });
 
     }
 
@@ -308,7 +307,9 @@ public void testPreconfiguredTokenFilters() throws IOException {
                 IllegalArgumentException e = expectThrows(
                     IllegalArgumentException.class,
                     "Expected exception for factory " + tf.getName(),
-                    () -> { tf.get(idxSettings, null, tf.getName(), settings).getSynonymFilter(); }
+                    () -> {
+                        tf.get(idxSettings, null, tf.getName(), settings).getSynonymFilter();
+                    }
                 );
                 assertEquals(tf.getName(), "Token filter [" + tf.getName() + "] cannot be used to parse synonyms", e.getMessage());
             } else {
diff --git a/modules/geo/src/test/java/org/opensearch/geo/search/aggregations/bucket/geogrid/GeoGridAggregatorTestCase.java b/modules/geo/src/test/java/org/opensearch/geo/search/aggregations/bucket/geogrid/GeoGridAggregatorTestCase.java
index d6153637f656d..d1c1d0e0d1ea8 100644
--- a/modules/geo/src/test/java/org/opensearch/geo/search/aggregations/bucket/geogrid/GeoGridAggregatorTestCase.java
+++ b/modules/geo/src/test/java/org/opensearch/geo/search/aggregations/bucket/geogrid/GeoGridAggregatorTestCase.java
@@ -123,7 +123,9 @@ public void testUnmapped() throws IOException {
             randomPrecision(),
             null,
             geoGrid -> { assertEquals(0, geoGrid.getBuckets().size()); },
-            iw -> { iw.addDocument(Collections.singleton(new LatLonDocValuesField(FIELD_NAME, 10D, 10D))); }
+            iw -> {
+                iw.addDocument(Collections.singleton(new LatLonDocValuesField(FIELD_NAME, 10D, 10D)));
+            }
         );
     }
 
diff --git a/modules/ingest-common/src/test/java/org/opensearch/ingest/common/AppendProcessorTests.java b/modules/ingest-common/src/test/java/org/opensearch/ingest/common/AppendProcessorTests.java
index 7caa63792f347..1cb1ad7e408f6 100644
--- a/modules/ingest-common/src/test/java/org/opensearch/ingest/common/AppendProcessorTests.java
+++ b/modules/ingest-common/src/test/java/org/opensearch/ingest/common/AppendProcessorTests.java
@@ -203,7 +203,7 @@ public void testAppendingUniqueValueToScalar() throws Exception {
         appendProcessor.execute(ingestDocument);
         List<?> list = ingestDocument.getFieldValue(field, List.class);
         assertThat(list.size(), equalTo(2));
-        assertThat(list, equalTo(org.opensearch.common.collect.List.of(originalValue, newValue)));
+        assertThat(list, equalTo(List.of(originalValue, newValue)));
     }
 
     public void testAppendingToListWithDuplicatesDisallowed() throws Exception {
diff --git a/modules/ingest-common/src/test/java/org/opensearch/ingest/common/ForEachProcessorTests.java b/modules/ingest-common/src/test/java/org/opensearch/ingest/common/ForEachProcessorTests.java
index f49d5492a09b3..241945e58fa06 100644
--- a/modules/ingest-common/src/test/java/org/opensearch/ingest/common/ForEachProcessorTests.java
+++ b/modules/ingest-common/src/test/java/org/opensearch/ingest/common/ForEachProcessorTests.java
@@ -226,12 +226,8 @@ public void testModifyFieldsOutsideArray() throws Exception {
             "values",
             new CompoundProcessor(
                 false,
-                org.opensearch.common.collect.List.of(
-                    new UppercaseProcessor("_tag_upper", null, "_ingest._value", false, "_ingest._value")
-                ),
-                org.opensearch.common.collect.List.of(
-                    new AppendProcessor("_tag", null, template, (model) -> (Collections.singletonList("added")), true)
-                )
+                List.of(new UppercaseProcessor("_tag_upper", null, "_ingest._value", false, "_ingest._value")),
+                List.of(new AppendProcessor("_tag", null, template, (model) -> (Collections.singletonList("added")), true))
             ),
             false
         );
diff --git a/modules/ingest-common/src/test/java/org/opensearch/ingest/common/GrokProcessorGetActionTests.java b/modules/ingest-common/src/test/java/org/opensearch/ingest/common/GrokProcessorGetActionTests.java
index 5ccf85dd53f0e..641d8cdc5bcfe 100644
--- a/modules/ingest-common/src/test/java/org/opensearch/ingest/common/GrokProcessorGetActionTests.java
+++ b/modules/ingest-common/src/test/java/org/opensearch/ingest/common/GrokProcessorGetActionTests.java
@@ -57,7 +57,7 @@
 import static org.mockito.Mockito.mock;
 
 public class GrokProcessorGetActionTests extends OpenSearchTestCase {
-    private static final Map<String, String> TEST_PATTERNS = org.opensearch.common.collect.Map.of("PATTERN2", "foo2", "PATTERN1", "foo1");
+    private static final Map<String, String> TEST_PATTERNS = Map.of("PATTERN2", "foo2", "PATTERN1", "foo1");
 
     public void testRequest() throws Exception {
         GrokProcessorGetAction.Request request = new GrokProcessorGetAction.Request(false);
diff --git a/modules/ingest-geoip/src/test/java/org/opensearch/ingest/geoip/IngestGeoIpPluginTests.java b/modules/ingest-geoip/src/test/java/org/opensearch/ingest/geoip/IngestGeoIpPluginTests.java
index 540d68b0982eb..31cd9e8ef2f6a 100644
--- a/modules/ingest-geoip/src/test/java/org/opensearch/ingest/geoip/IngestGeoIpPluginTests.java
+++ b/modules/ingest-geoip/src/test/java/org/opensearch/ingest/geoip/IngestGeoIpPluginTests.java
@@ -65,11 +65,9 @@ public void testThrowsFunctionsException() {
         GeoIpCache cache = new GeoIpCache(1);
         IllegalArgumentException ex = expectThrows(
             IllegalArgumentException.class,
-            () -> cache.putIfAbsent(
-                InetAddresses.forString("127.0.0.1"),
-                AbstractResponse.class,
-                ip -> { throw new IllegalArgumentException("bad"); }
-            )
+            () -> cache.putIfAbsent(InetAddresses.forString("127.0.0.1"), AbstractResponse.class, ip -> {
+                throw new IllegalArgumentException("bad");
+            })
         );
         assertEquals("bad", ex.getMessage());
     }
diff --git a/modules/lang-painless/src/test/java/org/opensearch/painless/DefBootstrapTests.java b/modules/lang-painless/src/test/java/org/opensearch/painless/DefBootstrapTests.java
index 9134d7a3c062b..d063a3fd5c0a6 100644
--- a/modules/lang-painless/src/test/java/org/opensearch/painless/DefBootstrapTests.java
+++ b/modules/lang-painless/src/test/java/org/opensearch/painless/DefBootstrapTests.java
@@ -157,21 +157,13 @@ public void testMegamorphic() throws Throwable {
         map.put("a", "b");
         assertEquals(2, (int) handle.invokeExact((Object) map));
 
-        final IllegalArgumentException iae = expectThrows(
-            IllegalArgumentException.class,
-            () -> { Integer.toString((int) handle.invokeExact(new Object())); }
-        );
+        final IllegalArgumentException iae = expectThrows(IllegalArgumentException.class, () -> {
+            Integer.toString((int) handle.invokeExact(new Object()));
+        });
         assertEquals("dynamic method [java.lang.Object, size/0] not found", iae.getMessage());
-        assertTrue(
-            "Does not fail inside ClassValue.computeValue()",
-            Arrays.stream(iae.getStackTrace())
-                .anyMatch(
-                    e -> {
-                        return e.getMethodName().equals("computeValue")
-                            && e.getClassName().startsWith("org.opensearch.painless.DefBootstrap$PIC$");
-                    }
-                )
-        );
+        assertTrue("Does not fail inside ClassValue.computeValue()", Arrays.stream(iae.getStackTrace()).anyMatch(e -> {
+            return e.getMethodName().equals("computeValue") && e.getClassName().startsWith("org.opensearch.painless.DefBootstrap$PIC$");
+        }));
     }
 
     // test operators with null guards
diff --git a/modules/lang-painless/src/test/java/org/opensearch/painless/FunctionRefTests.java b/modules/lang-painless/src/test/java/org/opensearch/painless/FunctionRefTests.java
index 2ed1fa49d0bda..065e0fbd1f4e2 100644
--- a/modules/lang-painless/src/test/java/org/opensearch/painless/FunctionRefTests.java
+++ b/modules/lang-painless/src/test/java/org/opensearch/painless/FunctionRefTests.java
@@ -268,18 +268,16 @@ public void testInterfaceStaticMethod() {
     }
 
     public void testMethodMissing() {
-        Exception e = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("List l = [2, 1]; l.sort(Integer::bogus); return l.get(0);"); }
-        );
+        Exception e = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("List l = [2, 1]; l.sort(Integer::bogus); return l.get(0);");
+        });
         assertThat(e.getMessage(), containsString("function reference [Integer::bogus/2] matching [java.util.Comparator"));
     }
 
     public void testQualifiedMethodMissing() {
-        Exception e = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("List l = [2, 1]; l.sort(java.time.Instant::bogus); return l.get(0);", false); }
-        );
+        Exception e = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("List l = [2, 1]; l.sort(java.time.Instant::bogus); return l.get(0);", false);
+        });
         assertThat(
             e.getMessage(),
             containsString("function reference [java.time.Instant::bogus/2] matching [java.util.Comparator, compare/2")
@@ -287,26 +285,23 @@ public void testQualifiedMethodMissing() {
     }
 
     public void testClassMissing() {
-        Exception e = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("List l = [2, 1]; l.sort(Bogus::bogus); return l.get(0);", false); }
-        );
+        Exception e = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("List l = [2, 1]; l.sort(Bogus::bogus); return l.get(0);", false);
+        });
         assertThat(e.getMessage(), endsWith("variable [Bogus] is not defined"));
     }
 
     public void testQualifiedClassMissing() {
-        Exception e = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("List l = [2, 1]; l.sort(org.joda.time.BogusDateTime::bogus); return l.get(0);", false); }
-        );
+        Exception e = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("List l = [2, 1]; l.sort(org.joda.time.BogusDateTime::bogus); return l.get(0);", false);
+        });
         assertEquals("variable [org.joda.time.BogusDateTime] is not defined", e.getMessage());
     }
 
     public void testNotFunctionalInterface() {
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("List l = new ArrayList(); l.add(2); l.add(1); l.add(Integer::bogus); return l.get(0);"); }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("List l = new ArrayList(); l.add(2); l.add(1); l.add(Integer::bogus); return l.get(0);");
+        });
         assertThat(
             expected.getMessage(),
             containsString("cannot convert function reference [Integer::bogus] to a non-functional interface [def]")
@@ -314,17 +309,15 @@ public void testNotFunctionalInterface() {
     }
 
     public void testIncompatible() {
-        expectScriptThrows(
-            ClassCastException.class,
-            () -> { exec("List l = new ArrayList(); l.add(2); l.add(1); l.sort(String::startsWith); return l.get(0);"); }
-        );
+        expectScriptThrows(ClassCastException.class, () -> {
+            exec("List l = new ArrayList(); l.add(2); l.add(1); l.sort(String::startsWith); return l.get(0);");
+        });
     }
 
     public void testWrongArity() {
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("Optional.empty().orElseGet(String::startsWith);"); }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("Optional.empty().orElseGet(String::startsWith);");
+        });
         assertThat(
             expected.getMessage(),
             containsString("function reference [String::startsWith/0] matching [java.util.function.Supplier")
@@ -332,18 +325,16 @@ public void testWrongArity() {
     }
 
     public void testWrongArityNotEnough() {
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("List l = new ArrayList(); l.add(2); l.add(1); l.sort(String::isEmpty);"); }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("List l = new ArrayList(); l.add(2); l.add(1); l.sort(String::isEmpty);");
+        });
         assertThat(expected.getMessage(), containsString("function reference [String::isEmpty/2] matching [java.util.Comparator"));
     }
 
     public void testWrongArityDef() {
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("def y = Optional.empty(); return y.orElseGet(String::startsWith);"); }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("def y = Optional.empty(); return y.orElseGet(String::startsWith);");
+        });
         assertThat(
             expected.getMessage(),
             containsString("function reference [String::startsWith/0] matching [java.util.function.Supplier")
@@ -351,38 +342,33 @@ public void testWrongArityDef() {
     }
 
     public void testWrongArityNotEnoughDef() {
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("def l = new ArrayList(); l.add(2); l.add(1); l.sort(String::isEmpty);"); }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("def l = new ArrayList(); l.add(2); l.add(1); l.sort(String::isEmpty);");
+        });
         assertThat(expected.getMessage(), containsString("function reference [String::isEmpty/2] matching [java.util.Comparator"));
     }
 
     public void testReturnVoid() {
-        Throwable expected = expectScriptThrows(
-            ClassCastException.class,
-            () -> { exec("StringBuilder b = new StringBuilder(); List l = [1, 2]; l.stream().mapToLong(b::setLength).sum();"); }
-        );
+        Throwable expected = expectScriptThrows(ClassCastException.class, () -> {
+            exec("StringBuilder b = new StringBuilder(); List l = [1, 2]; l.stream().mapToLong(b::setLength).sum();");
+        });
         assertThat(expected.getMessage(), containsString("Cannot cast from [void] to [long]."));
     }
 
     public void testReturnVoidDef() {
-        Exception expected = expectScriptThrows(
-            LambdaConversionException.class,
-            () -> { exec("StringBuilder b = new StringBuilder(); def l = [1, 2]; l.stream().mapToLong(b::setLength);"); }
-        );
+        Exception expected = expectScriptThrows(LambdaConversionException.class, () -> {
+            exec("StringBuilder b = new StringBuilder(); def l = [1, 2]; l.stream().mapToLong(b::setLength);");
+        });
         assertThat(expected.getMessage(), containsString("lambda expects return type [long], but found return type [void]"));
 
-        expected = expectScriptThrows(
-            LambdaConversionException.class,
-            () -> { exec("def b = new StringBuilder(); def l = [1, 2]; l.stream().mapToLong(b::setLength);"); }
-        );
+        expected = expectScriptThrows(LambdaConversionException.class, () -> {
+            exec("def b = new StringBuilder(); def l = [1, 2]; l.stream().mapToLong(b::setLength);");
+        });
         assertThat(expected.getMessage(), containsString("lambda expects return type [long], but found return type [void]"));
 
-        expected = expectScriptThrows(
-            LambdaConversionException.class,
-            () -> { exec("def b = new StringBuilder(); List l = [1, 2]; l.stream().mapToLong(b::setLength);"); }
-        );
+        expected = expectScriptThrows(LambdaConversionException.class, () -> {
+            exec("def b = new StringBuilder(); List l = [1, 2]; l.stream().mapToLong(b::setLength);");
+        });
         assertThat(expected.getMessage(), containsString("lambda expects return type [long], but found return type [void]"));
     }
 }
diff --git a/modules/lang-painless/src/test/java/org/opensearch/painless/FunctionTests.java b/modules/lang-painless/src/test/java/org/opensearch/painless/FunctionTests.java
index 77b6e8f0b3d5c..45efaa2c8a5a4 100644
--- a/modules/lang-painless/src/test/java/org/opensearch/painless/FunctionTests.java
+++ b/modules/lang-painless/src/test/java/org/opensearch/painless/FunctionTests.java
@@ -82,10 +82,9 @@ public void testReturnsAreUnboxedIfNeeded() {
     }
 
     public void testDuplicates() {
-        Exception expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("void test(int x) {x = 2;} void test(def y) {y = 3;} test()"); }
-        );
+        Exception expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("void test(int x) {x = 2;} void test(def y) {y = 3;} test()");
+        });
         assertThat(expected.getMessage(), containsString("found duplicate function"));
     }
 
@@ -108,23 +107,20 @@ public void testInfiniteLoop() {
 
     public void testReturnVoid() {
         assertEquals(null, exec("void test(StringBuilder b, int i) {b.setLength(i)} test(new StringBuilder(), 1)"));
-        Exception expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("int test(StringBuilder b, int i) {b.setLength(i)} test(new StringBuilder(), 1)"); }
-        );
+        Exception expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("int test(StringBuilder b, int i) {b.setLength(i)} test(new StringBuilder(), 1)");
+        });
         assertEquals(
             "invalid function definition: " + "not all paths provide a return value for function [test] with [2] parameters",
             expected.getMessage()
         );
-        expected = expectScriptThrows(
-            ClassCastException.class,
-            () -> { exec("int test(StringBuilder b, int i) {return b.setLength(i)} test(new StringBuilder(), 1)"); }
-        );
+        expected = expectScriptThrows(ClassCastException.class, () -> {
+            exec("int test(StringBuilder b, int i) {return b.setLength(i)} test(new StringBuilder(), 1)");
+        });
         assertEquals("Cannot cast from [void] to [int].", expected.getMessage());
-        expected = expectScriptThrows(
-            ClassCastException.class,
-            () -> { exec("def test(StringBuilder b, int i) {return b.setLength(i)} test(new StringBuilder(), 1)"); }
-        );
+        expected = expectScriptThrows(ClassCastException.class, () -> {
+            exec("def test(StringBuilder b, int i) {return b.setLength(i)} test(new StringBuilder(), 1)");
+        });
         assertEquals("Cannot cast from [void] to [def].", expected.getMessage());
     }
 }
diff --git a/modules/lang-painless/src/test/java/org/opensearch/painless/GeneralCastTests.java b/modules/lang-painless/src/test/java/org/opensearch/painless/GeneralCastTests.java
index 225dbd51819de..27930e2cb43d8 100644
--- a/modules/lang-painless/src/test/java/org/opensearch/painless/GeneralCastTests.java
+++ b/modules/lang-painless/src/test/java/org/opensearch/painless/GeneralCastTests.java
@@ -293,14 +293,12 @@ public void testIllegalExplicitConversionsDef() {
     }
 
     public void testIllegalVoidCasts() {
-        expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("def map = ['a': 1,'b': 2,'c': 3]; map.c = Collections.sort(new ArrayList(map.keySet()));"); }
-        );
-        expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("Map map = ['a': 1,'b': 2,'c': 3]; def x = new HashMap(); x.put(1, map.clear());"); }
-        );
+        expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("def map = ['a': 1,'b': 2,'c': 3]; map.c = Collections.sort(new ArrayList(map.keySet()));");
+        });
+        expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("Map map = ['a': 1,'b': 2,'c': 3]; def x = new HashMap(); x.put(1, map.clear());");
+        });
     }
 
     public void testBoxedDefCalls() {
diff --git a/modules/lang-painless/src/test/java/org/opensearch/painless/LambdaTests.java b/modules/lang-painless/src/test/java/org/opensearch/painless/LambdaTests.java
index c1b19522021b8..8d0cbb4018801 100644
--- a/modules/lang-painless/src/test/java/org/opensearch/painless/LambdaTests.java
+++ b/modules/lang-painless/src/test/java/org/opensearch/painless/LambdaTests.java
@@ -173,28 +173,19 @@ public void testTwoCaptures() {
     }
 
     public void testCapturesAreReadOnly() {
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> {
-                exec(
-                    "List l = new ArrayList(); l.add(1); l.add(1); " + "return l.stream().mapToInt(x -> { l = null; return x + 1 }).sum();"
-                );
-            }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("List l = new ArrayList(); l.add(1); l.add(1); " + "return l.stream().mapToInt(x -> { l = null; return x + 1 }).sum();");
+        });
         assertTrue(expected.getMessage().contains("is read-only"));
     }
 
     /** Lambda parameters shouldn't be able to mask a variable already in scope */
     public void testNoParamMasking() {
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> {
-                exec(
-                    "int x = 0; List l = new ArrayList(); l.add(1); l.add(1); "
-                        + "return l.stream().mapToInt(x -> { x += 1; return x }).sum();"
-                );
-            }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec(
+                "int x = 0; List l = new ArrayList(); l.add(1); l.add(1); " + "return l.stream().mapToInt(x -> { x += 1; return x }).sum();"
+            );
+        });
         assertTrue(expected.getMessage().contains("already defined"));
     }
 
@@ -214,36 +205,30 @@ public void testNestedCaptureParams() {
     }
 
     public void testWrongArity() {
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            false,
-            () -> { exec("Optional.empty().orElseGet(x -> x);"); }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, false, () -> {
+            exec("Optional.empty().orElseGet(x -> x);");
+        });
         assertTrue(expected.getMessage().contains("Incorrect number of parameters"));
     }
 
     public void testWrongArityDef() {
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("def y = Optional.empty(); return y.orElseGet(x -> x);"); }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("def y = Optional.empty(); return y.orElseGet(x -> x);");
+        });
         assertTrue(expected.getMessage(), expected.getMessage().contains("due to an incorrect number of arguments"));
     }
 
     public void testWrongArityNotEnough() {
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            false,
-            () -> { exec("List l = new ArrayList(); l.add(1); l.add(1); " + "return l.stream().mapToInt(() -> 5).sum();"); }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, false, () -> {
+            exec("List l = new ArrayList(); l.add(1); l.add(1); " + "return l.stream().mapToInt(() -> 5).sum();");
+        });
         assertTrue(expected.getMessage().contains("Incorrect number of parameters"));
     }
 
     public void testWrongArityNotEnoughDef() {
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("def l = new ArrayList(); l.add(1); l.add(1); " + "return l.stream().mapToInt(() -> 5).sum();"); }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("def l = new ArrayList(); l.add(1); l.add(1); " + "return l.stream().mapToInt(() -> 5).sum();");
+        });
         assertTrue(expected.getMessage(), expected.getMessage().contains("due to an incorrect number of arguments"));
     }
 
@@ -308,19 +293,17 @@ public void testReservedCapture() {
     }
 
     public void testReturnVoid() {
-        Throwable expected = expectScriptThrows(
-            ClassCastException.class,
-            () -> { exec("StringBuilder b = new StringBuilder(); List l = [1, 2]; l.stream().mapToLong(i -> b.setLength(i))"); }
-        );
+        Throwable expected = expectScriptThrows(ClassCastException.class, () -> {
+            exec("StringBuilder b = new StringBuilder(); List l = [1, 2]; l.stream().mapToLong(i -> b.setLength(i))");
+        });
         assertThat(expected.getMessage(), containsString("Cannot cast from [void] to [long]."));
     }
 
     public void testReturnVoidDef() {
         // If we can catch the error at compile time we do
-        Exception expected = expectScriptThrows(
-            ClassCastException.class,
-            () -> { exec("StringBuilder b = new StringBuilder(); def l = [1, 2]; l.stream().mapToLong(i -> b.setLength(i))"); }
-        );
+        Exception expected = expectScriptThrows(ClassCastException.class, () -> {
+            exec("StringBuilder b = new StringBuilder(); def l = [1, 2]; l.stream().mapToLong(i -> b.setLength(i))");
+        });
         assertThat(expected.getMessage(), containsString("Cannot cast from [void] to [def]."));
 
         // Otherwise we convert the void into a null
diff --git a/modules/lang-painless/src/test/java/org/opensearch/painless/OverloadTests.java b/modules/lang-painless/src/test/java/org/opensearch/painless/OverloadTests.java
index 16f3c16a59548..02fa18ec07178 100644
--- a/modules/lang-painless/src/test/java/org/opensearch/painless/OverloadTests.java
+++ b/modules/lang-painless/src/test/java/org/opensearch/painless/OverloadTests.java
@@ -38,20 +38,18 @@ public class OverloadTests extends ScriptTestCase {
     public void testMethod() {
         // assertEquals(2, exec("return 'abc123abc'.indexOf('c');"));
         // assertEquals(8, exec("return 'abc123abc'.indexOf('c', 3);"));
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("return 'abc123abc'.indexOf('c', 3, 'bogus');"); }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("return 'abc123abc'.indexOf('c', 3, 'bogus');");
+        });
         assertTrue(expected.getMessage().contains("[java.lang.String, indexOf/3]"));
     }
 
     public void testMethodDynamic() {
         assertEquals(2, exec("def x = 'abc123abc'; return x.indexOf('c');"));
         assertEquals(8, exec("def x = 'abc123abc'; return x.indexOf('c', 3);"));
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("def x = 'abc123abc'; return x.indexOf('c', 3, 'bogus');"); }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("def x = 'abc123abc'; return x.indexOf('c', 3, 'bogus');");
+        });
         assertTrue(expected.getMessage().contains("dynamic method [java.lang.String, indexOf/3] not found"));
     }
 
diff --git a/modules/lang-painless/src/test/java/org/opensearch/painless/StringTests.java b/modules/lang-painless/src/test/java/org/opensearch/painless/StringTests.java
index d344a9c2a31f1..b9586924d4fcd 100644
--- a/modules/lang-painless/src/test/java/org/opensearch/painless/StringTests.java
+++ b/modules/lang-painless/src/test/java/org/opensearch/painless/StringTests.java
@@ -182,11 +182,9 @@ public void testStringAndCharacter() {
         assertEquals('c', exec("String s = \"c\"; (char)s"));
         assertEquals('c', exec("String s = 'c'; (char)s"));
 
-        ClassCastException expected = expectScriptThrows(
-            ClassCastException.class,
-            false,
-            () -> { assertEquals("cc", exec("return (String)(char)\"cc\"")); }
-        );
+        ClassCastException expected = expectScriptThrows(ClassCastException.class, false, () -> {
+            assertEquals("cc", exec("return (String)(char)\"cc\""));
+        });
         assertTrue(expected.getMessage().contains("cannot cast java.lang.String with length not equal to one to char"));
 
         expected = expectScriptThrows(ClassCastException.class, false, () -> { assertEquals("cc", exec("return (String)(char)'cc'")); });
diff --git a/modules/lang-painless/src/test/java/org/opensearch/painless/WhenThingsGoWrongTests.java b/modules/lang-painless/src/test/java/org/opensearch/painless/WhenThingsGoWrongTests.java
index fb8d2eccfa043..3f12bf57a0e33 100644
--- a/modules/lang-painless/src/test/java/org/opensearch/painless/WhenThingsGoWrongTests.java
+++ b/modules/lang-painless/src/test/java/org/opensearch/painless/WhenThingsGoWrongTests.java
@@ -57,10 +57,9 @@ public void testNullPointer() {
     public void testScriptStack() {
         for (String type : new String[] { "String", "def   " }) {
             // trigger NPE at line 1 of the script
-            ScriptException exception = expectThrows(
-                ScriptException.class,
-                () -> { exec(type + " x = null; boolean y = x.isEmpty();\n" + "return y;"); }
-            );
+            ScriptException exception = expectThrows(ScriptException.class, () -> {
+                exec(type + " x = null; boolean y = x.isEmpty();\n" + "return y;");
+            });
             // null deref at x.isEmpty(), the '.' is offset 30
             assertScriptElementColumn(30, exception);
             assertScriptStack(exception, "y = x.isEmpty();\n", "     ^---- HERE");
@@ -84,12 +83,9 @@ public void testScriptStack() {
             assertThat(exception.getCause(), instanceOf(NullPointerException.class));
 
             // trigger NPE at line 4 in script (inside conditional)
-            exception = expectThrows(
-                ScriptException.class,
-                () -> {
-                    exec(type + " x = null;\n" + "boolean y = false;\n" + "if (!y) {\n" + "  y = x.isEmpty();\n" + "}\n" + "return y;");
-                }
-            );
+            exception = expectThrows(ScriptException.class, () -> {
+                exec(type + " x = null;\n" + "boolean y = false;\n" + "if (!y) {\n" + "  y = x.isEmpty();\n" + "}\n" + "return y;");
+            });
             // null deref at x.isEmpty(), the '.' is offset 53
             assertScriptElementColumn(53, exception);
             assertScriptStack(exception, "y = x.isEmpty();\n}\n", "     ^---- HERE");
@@ -121,10 +117,9 @@ public void testInvalidShift() {
     }
 
     public void testBogusParameter() {
-        IllegalArgumentException expected = expectThrows(
-            IllegalArgumentException.class,
-            () -> { exec("return 5;", null, Collections.singletonMap("bogusParameterKey", "bogusParameterValue"), true); }
-        );
+        IllegalArgumentException expected = expectThrows(IllegalArgumentException.class, () -> {
+            exec("return 5;", null, Collections.singletonMap("bogusParameterKey", "bogusParameterValue"), true);
+        });
         assertTrue(expected.getMessage().contains("Unrecognized compile-time parameter"));
     }
 
@@ -178,10 +173,9 @@ public void testLoopLimits() {
     }
 
     public void testIllegalDynamicMethod() {
-        IllegalArgumentException expected = expectScriptThrows(
-            IllegalArgumentException.class,
-            () -> { exec("def x = 'test'; return x.getClass().toString()"); }
-        );
+        IllegalArgumentException expected = expectScriptThrows(IllegalArgumentException.class, () -> {
+            exec("def x = 'test'; return x.getClass().toString()");
+        });
         assertTrue(expected.getMessage().contains("dynamic method [java.lang.String, getClass/0] not found"));
     }
 
diff --git a/modules/lang-painless/src/test/java/org/opensearch/painless/WhitelistLoaderTests.java b/modules/lang-painless/src/test/java/org/opensearch/painless/WhitelistLoaderTests.java
index e4e754a541414..b7ba3040894e3 100644
--- a/modules/lang-painless/src/test/java/org/opensearch/painless/WhitelistLoaderTests.java
+++ b/modules/lang-painless/src/test/java/org/opensearch/painless/WhitelistLoaderTests.java
@@ -47,19 +47,15 @@ public class WhitelistLoaderTests extends ScriptTestCase {
     public void testUnknownAnnotations() {
         Map<String, WhitelistAnnotationParser> parsers = new HashMap<>(WhitelistAnnotationParser.BASE_ANNOTATION_PARSERS);
 
-        RuntimeException expected = expectThrows(
-            RuntimeException.class,
-            () -> { WhitelistLoader.loadFromResourceFiles(Whitelist.class, parsers, "org.opensearch.painless.annotation.unknown"); }
-        );
+        RuntimeException expected = expectThrows(RuntimeException.class, () -> {
+            WhitelistLoader.loadFromResourceFiles(Whitelist.class, parsers, "org.opensearch.painless.annotation.unknown");
+        });
         assertEquals("invalid annotation: parser not found for [unknownAnnotation] [@unknownAnnotation]", expected.getCause().getMessage());
         assertEquals(IllegalArgumentException.class, expected.getCause().getClass());
 
-        expected = expectThrows(
-            RuntimeException.class,
-            () -> {
-                WhitelistLoader.loadFromResourceFiles(Whitelist.class, parsers, "org.opensearch.painless.annotation.unknown_with_options");
-            }
-        );
+        expected = expectThrows(RuntimeException.class, () -> {
+            WhitelistLoader.loadFromResourceFiles(Whitelist.class, parsers, "org.opensearch.painless.annotation.unknown_with_options");
+        });
         assertEquals(
             "invalid annotation: parser not found for [unknownAnootationWithMessage] [@unknownAnootationWithMessage[arg=\"arg value\"]]",
             expected.getCause().getMessage()
diff --git a/modules/mapper-extras/src/main/java/org/opensearch/index/mapper/TokenCountFieldMapper.java b/modules/mapper-extras/src/main/java/org/opensearch/index/mapper/TokenCountFieldMapper.java
index fd029503e9a7b..1851afcf0af85 100644
--- a/modules/mapper-extras/src/main/java/org/opensearch/index/mapper/TokenCountFieldMapper.java
+++ b/modules/mapper-extras/src/main/java/org/opensearch/index/mapper/TokenCountFieldMapper.java
@@ -122,7 +122,7 @@ static class TokenCountFieldType extends NumberFieldMapper.NumberFieldType {
         @Override
         public ValueFetcher valueFetcher(QueryShardContext context, SearchLookup searchLookup, String format) {
             if (hasDocValues() == false) {
-                return lookup -> org.opensearch.common.collect.List.of();
+                return lookup -> List.of();
             }
             return new DocValueFetcher(docValueFormat(format, null), searchLookup.doc().getForField(this));
         }
diff --git a/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/RankFeatureFieldMapperTests.java b/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/RankFeatureFieldMapperTests.java
index 908e5db6196c3..7fcbb2045d0de 100644
--- a/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/RankFeatureFieldMapperTests.java
+++ b/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/RankFeatureFieldMapperTests.java
@@ -39,13 +39,13 @@
 import org.apache.lucene.search.Query;
 import org.apache.lucene.search.TermQuery;
 import org.opensearch.common.Strings;
-import org.opensearch.common.collect.List;
 import org.opensearch.common.xcontent.XContentBuilder;
 import org.opensearch.plugins.Plugin;
 
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.List;
 
 import static org.hamcrest.Matchers.instanceOf;
 
diff --git a/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/RankFeaturesFieldMapperTests.java b/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/RankFeaturesFieldMapperTests.java
index 55d825d1b53bb..5ddbff1cf8708 100644
--- a/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/RankFeaturesFieldMapperTests.java
+++ b/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/RankFeaturesFieldMapperTests.java
@@ -42,6 +42,7 @@
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.List;
 
 public class RankFeaturesFieldMapperTests extends MapperTestCase {
 
@@ -58,7 +59,7 @@ protected void assertExistsQuery(MapperService mapperService) {
 
     @Override
     protected Collection<? extends Plugin> getPlugins() {
-        return org.opensearch.common.collect.List.of(new MapperExtrasPlugin());
+        return List.of(new MapperExtrasPlugin());
     }
 
     @Override
diff --git a/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/SearchAsYouTypeFieldMapperTests.java b/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/SearchAsYouTypeFieldMapperTests.java
index d320a279bbfc5..0ba132596e16c 100644
--- a/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/SearchAsYouTypeFieldMapperTests.java
+++ b/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/SearchAsYouTypeFieldMapperTests.java
@@ -76,6 +76,7 @@
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
+import java.util.Map;
 import java.util.Set;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
@@ -134,7 +135,7 @@ protected void writeFieldValue(XContentBuilder builder) throws IOException {
 
     @Override
     protected Collection<? extends Plugin> getPlugins() {
-        return org.opensearch.common.collect.List.of(new MapperExtrasPlugin());
+        return List.of(new MapperExtrasPlugin());
     }
 
     @Override
@@ -150,20 +151,9 @@ protected IndexAnalyzers createIndexAnalyzers(IndexSettings indexSettings) {
         NamedAnalyzer simple = new NamedAnalyzer("simple", AnalyzerScope.INDEX, new SimpleAnalyzer());
         NamedAnalyzer whitespace = new NamedAnalyzer("whitespace", AnalyzerScope.INDEX, new WhitespaceAnalyzer());
         return new IndexAnalyzers(
-            org.opensearch.common.collect.Map.of(
-                "default",
-                dflt,
-                "standard",
-                standard,
-                "keyword",
-                keyword,
-                "simple",
-                simple,
-                "whitespace",
-                whitespace
-            ),
-            org.opensearch.common.collect.Map.of(),
-            org.opensearch.common.collect.Map.of()
+            Map.of("default", dflt, "standard", standard, "keyword", keyword, "simple", simple, "whitespace", whitespace),
+            Map.of(),
+            Map.of()
         );
     }
 
diff --git a/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/SearchAsYouTypeFieldTypeTests.java b/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/SearchAsYouTypeFieldTypeTests.java
index 1998465318c2b..77e34560d4cad 100644
--- a/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/SearchAsYouTypeFieldTypeTests.java
+++ b/modules/mapper-extras/src/test/java/org/opensearch/index/mapper/SearchAsYouTypeFieldTypeTests.java
@@ -49,6 +49,7 @@
 
 import java.io.IOException;
 import java.util.Collections;
+import java.util.List;
 
 import static java.util.Arrays.asList;
 import static org.apache.lucene.search.MultiTermQuery.CONSTANT_SCORE_REWRITE;
@@ -154,9 +155,9 @@ public void testFetchSourceValue() throws IOException {
         SearchAsYouTypeFieldType fieldType = createFieldType();
         fieldType.setIndexAnalyzer(Lucene.STANDARD_ANALYZER);
 
-        assertEquals(org.opensearch.common.collect.List.of("value"), fetchSourceValue(fieldType, "value"));
-        assertEquals(org.opensearch.common.collect.List.of("42"), fetchSourceValue(fieldType, 42L));
-        assertEquals(org.opensearch.common.collect.List.of("true"), fetchSourceValue(fieldType, true));
+        assertEquals(List.of("value"), fetchSourceValue(fieldType, "value"));
+        assertEquals(List.of("42"), fetchSourceValue(fieldType, 42L));
+        assertEquals(List.of("true"), fetchSourceValue(fieldType, true));
 
         SearchAsYouTypeFieldMapper.PrefixFieldType prefixFieldType = new SearchAsYouTypeFieldMapper.PrefixFieldType(
             fieldType.name(),
@@ -164,17 +165,17 @@ public void testFetchSourceValue() throws IOException {
             2,
             10
         );
-        assertEquals(org.opensearch.common.collect.List.of("value"), fetchSourceValue(prefixFieldType, "value"));
-        assertEquals(org.opensearch.common.collect.List.of("42"), fetchSourceValue(prefixFieldType, 42L));
-        assertEquals(org.opensearch.common.collect.List.of("true"), fetchSourceValue(prefixFieldType, true));
+        assertEquals(List.of("value"), fetchSourceValue(prefixFieldType, "value"));
+        assertEquals(List.of("42"), fetchSourceValue(prefixFieldType, 42L));
+        assertEquals(List.of("true"), fetchSourceValue(prefixFieldType, true));
 
         SearchAsYouTypeFieldMapper.ShingleFieldType shingleFieldType = new SearchAsYouTypeFieldMapper.ShingleFieldType(
             fieldType.name(),
             5,
             fieldType.getTextSearchInfo()
         );
-        assertEquals(org.opensearch.common.collect.List.of("value"), fetchSourceValue(shingleFieldType, "value"));
-        assertEquals(org.opensearch.common.collect.List.of("42"), fetchSourceValue(shingleFieldType, 42L));
-        assertEquals(org.opensearch.common.collect.List.of("true"), fetchSourceValue(shingleFieldType, true));
+        assertEquals(List.of("value"), fetchSourceValue(shingleFieldType, "value"));
+        assertEquals(List.of("42"), fetchSourceValue(shingleFieldType, 42L));
+        assertEquals(List.of("true"), fetchSourceValue(shingleFieldType, true));
     }
 }
diff --git a/modules/percolator/src/internalClusterTest/java/org/opensearch/percolator/PercolatorQuerySearchIT.java b/modules/percolator/src/internalClusterTest/java/org/opensearch/percolator/PercolatorQuerySearchIT.java
index b318a504ab7e7..3a07ba907be33 100644
--- a/modules/percolator/src/internalClusterTest/java/org/opensearch/percolator/PercolatorQuerySearchIT.java
+++ b/modules/percolator/src/internalClusterTest/java/org/opensearch/percolator/PercolatorQuerySearchIT.java
@@ -436,10 +436,9 @@ public void testPercolatorQueryExistingDocumentSourceDisabled() throws Exception
         client().admin().indices().prepareRefresh().get();
 
         logger.info("percolating empty doc with source disabled");
-        IllegalArgumentException e = expectThrows(
-            IllegalArgumentException.class,
-            () -> { client().prepareSearch().setQuery(new PercolateQueryBuilder("query", "test", "1", null, null, null)).get(); }
-        );
+        IllegalArgumentException e = expectThrows(IllegalArgumentException.class, () -> {
+            client().prepareSearch().setQuery(new PercolateQueryBuilder("query", "test", "1", null, null, null)).get();
+        });
         assertThat(e.getMessage(), containsString("source disabled"));
     }
 
diff --git a/modules/percolator/src/test/java/org/opensearch/percolator/PercolateQueryBuilderTests.java b/modules/percolator/src/test/java/org/opensearch/percolator/PercolateQueryBuilderTests.java
index 87aa28a3346bc..6f2fe980f44ee 100644
--- a/modules/percolator/src/test/java/org/opensearch/percolator/PercolateQueryBuilderTests.java
+++ b/modules/percolator/src/test/java/org/opensearch/percolator/PercolateQueryBuilderTests.java
@@ -245,10 +245,9 @@ protected Set<String> getObjectsHoldingArbitraryContent() {
     }
 
     public void testRequiredParameters() {
-        IllegalArgumentException e = expectThrows(
-            IllegalArgumentException.class,
-            () -> { new PercolateQueryBuilder(null, new BytesArray("{}"), XContentType.JSON); }
-        );
+        IllegalArgumentException e = expectThrows(IllegalArgumentException.class, () -> {
+            new PercolateQueryBuilder(null, new BytesArray("{}"), XContentType.JSON);
+        });
         assertThat(e.getMessage(), equalTo("[field] is a required argument"));
 
         e = expectThrows(
diff --git a/modules/rank-eval/src/main/java/org/opensearch/index/rankeval/DiscountedCumulativeGain.java b/modules/rank-eval/src/main/java/org/opensearch/index/rankeval/DiscountedCumulativeGain.java
index 35db325b70ca5..ded1df2f43de5 100644
--- a/modules/rank-eval/src/main/java/org/opensearch/index/rankeval/DiscountedCumulativeGain.java
+++ b/modules/rank-eval/src/main/java/org/opensearch/index/rankeval/DiscountedCumulativeGain.java
@@ -282,11 +282,9 @@ public XContentBuilder innerToXContent(XContentBuilder builder, Params params) t
             return builder;
         }
 
-        private static final ConstructingObjectParser<Detail, Void> PARSER = new ConstructingObjectParser<>(
-            NAME,
-            true,
-            args -> { return new Detail((Double) args[0], (Double) args[1] != null ? (Double) args[1] : 0.0d, (Integer) args[2]); }
-        );
+        private static final ConstructingObjectParser<Detail, Void> PARSER = new ConstructingObjectParser<>(NAME, true, args -> {
+            return new Detail((Double) args[0], (Double) args[1] != null ? (Double) args[1] : 0.0d, (Integer) args[2]);
+        });
 
         static {
             PARSER.declareDouble(constructorArg(), DCG_FIELD);
diff --git a/modules/rank-eval/src/main/java/org/opensearch/index/rankeval/ExpectedReciprocalRank.java b/modules/rank-eval/src/main/java/org/opensearch/index/rankeval/ExpectedReciprocalRank.java
index 3557e0576bb05..af699c65eb332 100644
--- a/modules/rank-eval/src/main/java/org/opensearch/index/rankeval/ExpectedReciprocalRank.java
+++ b/modules/rank-eval/src/main/java/org/opensearch/index/rankeval/ExpectedReciprocalRank.java
@@ -262,11 +262,9 @@ public XContentBuilder innerToXContent(XContentBuilder builder, Params params) t
             return builder.field(UNRATED_FIELD.getPreferredName(), this.unratedDocs);
         }
 
-        private static final ConstructingObjectParser<Detail, Void> PARSER = new ConstructingObjectParser<>(
-            NAME,
-            true,
-            args -> { return new Detail((Integer) args[0]); }
-        );
+        private static final ConstructingObjectParser<Detail, Void> PARSER = new ConstructingObjectParser<>(NAME, true, args -> {
+            return new Detail((Integer) args[0]);
+        });
 
         static {
             PARSER.declareInt(constructorArg(), UNRATED_FIELD);
diff --git a/modules/rank-eval/src/main/java/org/opensearch/index/rankeval/MeanReciprocalRank.java b/modules/rank-eval/src/main/java/org/opensearch/index/rankeval/MeanReciprocalRank.java
index 59792537e89e5..6ccecadd2d7f8 100644
--- a/modules/rank-eval/src/main/java/org/opensearch/index/rankeval/MeanReciprocalRank.java
+++ b/modules/rank-eval/src/main/java/org/opensearch/index/rankeval/MeanReciprocalRank.java
@@ -219,11 +219,9 @@ public XContentBuilder innerToXContent(XContentBuilder builder, Params params) t
             return builder.field(FIRST_RELEVANT_RANK_FIELD.getPreferredName(), firstRelevantRank);
         }
 
-        private static final ConstructingObjectParser<Detail, Void> PARSER = new ConstructingObjectParser<>(
-            NAME,
-            true,
-            args -> { return new Detail((Integer) args[0]); }
-        );
+        private static final ConstructingObjectParser<Detail, Void> PARSER = new ConstructingObjectParser<>(NAME, true, args -> {
+            return new Detail((Integer) args[0]);
+        });
 
         static {
             PARSER.declareInt(constructorArg(), FIRST_RELEVANT_RANK_FIELD);
diff --git a/modules/rank-eval/src/test/java/org/opensearch/index/rankeval/DiscountedCumulativeGainTests.java b/modules/rank-eval/src/test/java/org/opensearch/index/rankeval/DiscountedCumulativeGainTests.java
index 2bf229b094245..2537886ddf577 100644
--- a/modules/rank-eval/src/test/java/org/opensearch/index/rankeval/DiscountedCumulativeGainTests.java
+++ b/modules/rank-eval/src/test/java/org/opensearch/index/rankeval/DiscountedCumulativeGainTests.java
@@ -346,11 +346,9 @@ public void testSerialization() throws IOException {
     }
 
     public void testEqualsAndHash() throws IOException {
-        checkEqualsAndHashCode(
-            createTestItem(),
-            original -> { return new DiscountedCumulativeGain(original.getNormalize(), original.getUnknownDocRating(), original.getK()); },
-            DiscountedCumulativeGainTests::mutateTestItem
-        );
+        checkEqualsAndHashCode(createTestItem(), original -> {
+            return new DiscountedCumulativeGain(original.getNormalize(), original.getUnknownDocRating(), original.getK());
+        }, DiscountedCumulativeGainTests::mutateTestItem);
     }
 
     private static DiscountedCumulativeGain mutateTestItem(DiscountedCumulativeGain original) {
diff --git a/modules/rank-eval/src/test/java/org/opensearch/index/rankeval/ExpectedReciprocalRankTests.java b/modules/rank-eval/src/test/java/org/opensearch/index/rankeval/ExpectedReciprocalRankTests.java
index 723a1e2202e2b..1b39f4e07efa5 100644
--- a/modules/rank-eval/src/test/java/org/opensearch/index/rankeval/ExpectedReciprocalRankTests.java
+++ b/modules/rank-eval/src/test/java/org/opensearch/index/rankeval/ExpectedReciprocalRankTests.java
@@ -213,11 +213,9 @@ public void testSerialization() throws IOException {
     }
 
     public void testEqualsAndHash() throws IOException {
-        checkEqualsAndHashCode(
-            createTestItem(),
-            original -> { return new ExpectedReciprocalRank(original.getMaxRelevance(), original.getUnknownDocRating(), original.getK()); },
-            ExpectedReciprocalRankTests::mutateTestItem
-        );
+        checkEqualsAndHashCode(createTestItem(), original -> {
+            return new ExpectedReciprocalRank(original.getMaxRelevance(), original.getUnknownDocRating(), original.getK());
+        }, ExpectedReciprocalRankTests::mutateTestItem);
     }
 
     private static ExpectedReciprocalRank mutateTestItem(ExpectedReciprocalRank original) {
diff --git a/modules/rank-eval/src/test/java/org/opensearch/index/rankeval/RatedDocumentTests.java b/modules/rank-eval/src/test/java/org/opensearch/index/rankeval/RatedDocumentTests.java
index f3fb01b153c55..042bf22765ade 100644
--- a/modules/rank-eval/src/test/java/org/opensearch/index/rankeval/RatedDocumentTests.java
+++ b/modules/rank-eval/src/test/java/org/opensearch/index/rankeval/RatedDocumentTests.java
@@ -91,11 +91,9 @@ public void testSerialization() throws IOException {
     }
 
     public void testEqualsAndHash() throws IOException {
-        checkEqualsAndHashCode(
-            createRatedDocument(),
-            original -> { return new RatedDocument(original.getIndex(), original.getDocID(), original.getRating()); },
-            RatedDocumentTests::mutateTestItem
-        );
+        checkEqualsAndHashCode(createRatedDocument(), original -> {
+            return new RatedDocument(original.getIndex(), original.getDocID(), original.getRating());
+        }, RatedDocumentTests::mutateTestItem);
     }
 
     private static RatedDocument mutateTestItem(RatedDocument original) {
diff --git a/modules/reindex/src/test/java/org/opensearch/index/reindex/ClientScrollableHitSourceTests.java b/modules/reindex/src/test/java/org/opensearch/index/reindex/ClientScrollableHitSourceTests.java
index 9333e5bd3dcc9..3a79a0b35e391 100644
--- a/modules/reindex/src/test/java/org/opensearch/index/reindex/ClientScrollableHitSourceTests.java
+++ b/modules/reindex/src/test/java/org/opensearch/index/reindex/ClientScrollableHitSourceTests.java
@@ -105,10 +105,9 @@ private static class ExpectedException extends RuntimeException {
 
     public void testRetryFail() {
         int retries = randomInt(10);
-        ExpectedException ex = expectThrows(
-            ExpectedException.class,
-            () -> { dotestBasicsWithRetry(retries, retries + 1, retries + 1, e -> { throw new ExpectedException(e); }); }
-        );
+        ExpectedException ex = expectThrows(ExpectedException.class, () -> {
+            dotestBasicsWithRetry(retries, retries + 1, retries + 1, e -> { throw new ExpectedException(e); });
+        });
         assertThat(ex.getCause(), instanceOf(OpenSearchRejectedExecutionException.class));
     }
 
diff --git a/modules/repository-url/src/yamlRestTest/resources/rest-api-spec/test/repository_url/20_repository.yml b/modules/repository-url/src/yamlRestTest/resources/rest-api-spec/test/repository_url/20_repository.yml
index f40ad16bb4265..cc6b3b5ce1f33 100644
--- a/modules/repository-url/src/yamlRestTest/resources/rest-api-spec/test/repository_url/20_repository.yml
+++ b/modules/repository-url/src/yamlRestTest/resources/rest-api-spec/test/repository_url/20_repository.yml
@@ -27,6 +27,3 @@
           type: url
           settings:
             url: "http://snapshot.unknown"
-
-
-    
diff --git a/modules/transport-netty4/licenses/netty-buffer-4.1.87.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-buffer-4.1.87.Final.jar.sha1
deleted file mode 100644
index 8350f48acdb54..0000000000000
--- a/modules/transport-netty4/licenses/netty-buffer-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-8942174141fb0586e7fffefc8ae48e1458293696
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-buffer-4.1.90.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-buffer-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..67604d11c1eca
--- /dev/null
+++ b/modules/transport-netty4/licenses/netty-buffer-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+937eb60c19c5f5c1326b96123c9ec3d33238d4d5
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-codec-4.1.87.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-codec-4.1.87.Final.jar.sha1
deleted file mode 100644
index 9a494c68b7afb..0000000000000
--- a/modules/transport-netty4/licenses/netty-codec-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-d7ab7363f736114e6324ccf802d094529b30b8d8
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-codec-4.1.90.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-codec-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..c8fb04a021807
--- /dev/null
+++ b/modules/transport-netty4/licenses/netty-codec-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+9992a22c82e18b8fd4f34989535f3e504e55aa37
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-codec-http-4.1.87.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-codec-http-4.1.87.Final.jar.sha1
deleted file mode 100644
index 115657578cf80..0000000000000
--- a/modules/transport-netty4/licenses/netty-codec-http-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-3230e95d6832ee4306fe1ca774c7bcecf1da4b28
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-codec-http-4.1.90.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-codec-http-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..861599ce1d1d2
--- /dev/null
+++ b/modules/transport-netty4/licenses/netty-codec-http-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+19bbcd46f8ee0d118486f98eff22fe665b9689e5
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-common-4.1.87.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-common-4.1.87.Final.jar.sha1
deleted file mode 100644
index 066550b9e0135..0000000000000
--- a/modules/transport-netty4/licenses/netty-common-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-3e7e80dd6e604144781fcb859b79cfe8d3730079
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-common-4.1.90.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-common-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..afb531805329e
--- /dev/null
+++ b/modules/transport-netty4/licenses/netty-common-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+43597a09382c6ae2bef469a9b3a41e8a17850638
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-handler-4.1.87.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-handler-4.1.87.Final.jar.sha1
deleted file mode 100644
index 0923602100814..0000000000000
--- a/modules/transport-netty4/licenses/netty-handler-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-2bd97491c22ebea4670c00f1bd5dbf65a8a1cfe7
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-handler-4.1.90.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-handler-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..c98bfb52393d6
--- /dev/null
+++ b/modules/transport-netty4/licenses/netty-handler-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+64f6946ce4d9189cec5341d3f5f86ac5653099b5
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-resolver-4.1.87.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-resolver-4.1.87.Final.jar.sha1
deleted file mode 100644
index 4465a47bd49fb..0000000000000
--- a/modules/transport-netty4/licenses/netty-resolver-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-eaa964e16a67914c8d9b814d29a4b969635d72a0
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-resolver-4.1.90.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-resolver-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..b92177828aa56
--- /dev/null
+++ b/modules/transport-netty4/licenses/netty-resolver-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+47c415d8c83f08b820ba00e6497a6cf19dd0155f
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-transport-4.1.87.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-transport-4.1.87.Final.jar.sha1
deleted file mode 100644
index dcb49c515e460..0000000000000
--- a/modules/transport-netty4/licenses/netty-transport-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-30c78c8ced3417f35e2a55f7533dc2bb43fef2aa
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-transport-4.1.90.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-transport-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..c7a77dbf6aaa8
--- /dev/null
+++ b/modules/transport-netty4/licenses/netty-transport-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+82d68da212f62b076c763f5efa9b072d2abc018f
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-transport-native-unix-common-4.1.87.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-transport-native-unix-common-4.1.87.Final.jar.sha1
deleted file mode 100644
index 4fb195e5f08f6..0000000000000
--- a/modules/transport-netty4/licenses/netty-transport-native-unix-common-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-4bf8308dc7d6ba2570681eaeddb16f8d1196b438
\ No newline at end of file
diff --git a/modules/transport-netty4/licenses/netty-transport-native-unix-common-4.1.90.Final.jar.sha1 b/modules/transport-netty4/licenses/netty-transport-native-unix-common-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..5f954b2595927
--- /dev/null
+++ b/modules/transport-netty4/licenses/netty-transport-native-unix-common-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+e42282002cf22105e7e993651aead231246d0220
\ No newline at end of file
diff --git a/plugins/analysis-icu/src/test/java/org/opensearch/index/analysis/IcuAnalyzerTests.java b/plugins/analysis-icu/src/test/java/org/opensearch/index/analysis/IcuAnalyzerTests.java
index e490248fc8122..c363bc6eb43f8 100644
--- a/plugins/analysis-icu/src/test/java/org/opensearch/index/analysis/IcuAnalyzerTests.java
+++ b/plugins/analysis-icu/src/test/java/org/opensearch/index/analysis/IcuAnalyzerTests.java
@@ -90,10 +90,9 @@ public void testBadSettings() {
         Settings settings = Settings.builder().put(IndexMetadata.SETTING_VERSION_CREATED, Version.CURRENT).put("mode", "wrong").build();
         IndexSettings idxSettings = IndexSettingsModule.newIndexSettings("index", settings);
 
-        IllegalArgumentException e = expectThrows(
-            IllegalArgumentException.class,
-            () -> { new IcuAnalyzerProvider(idxSettings, null, "icu", settings); }
-        );
+        IllegalArgumentException e = expectThrows(IllegalArgumentException.class, () -> {
+            new IcuAnalyzerProvider(idxSettings, null, "icu", settings);
+        });
 
         assertThat(e.getMessage(), containsString("Unknown mode [wrong] in analyzer [icu], expected one of [compose, decompose]"));
 
diff --git a/plugins/analysis-icu/src/test/java/org/opensearch/index/mapper/ICUCollationKeywordFieldMapperTests.java b/plugins/analysis-icu/src/test/java/org/opensearch/index/mapper/ICUCollationKeywordFieldMapperTests.java
index 0cf82c408ae6f..a784e312b4463 100644
--- a/plugins/analysis-icu/src/test/java/org/opensearch/index/mapper/ICUCollationKeywordFieldMapperTests.java
+++ b/plugins/analysis-icu/src/test/java/org/opensearch/index/mapper/ICUCollationKeywordFieldMapperTests.java
@@ -40,7 +40,6 @@
 import org.apache.lucene.index.IndexableFieldType;
 import org.apache.lucene.util.BytesRef;
 import org.opensearch.common.Strings;
-import org.opensearch.common.collect.List;
 import org.opensearch.common.xcontent.XContentBuilder;
 import org.opensearch.plugin.analysis.icu.AnalysisICUPlugin;
 import org.opensearch.plugins.Plugin;
@@ -48,6 +47,7 @@
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.List;
 import java.util.Set;
 
 import static org.hamcrest.Matchers.containsString;
@@ -69,7 +69,7 @@ protected ICUCollationKeywordFieldMapper.Builder newBuilder() {
 
     @Override
     protected Set<String> unsupportedProperties() {
-        return org.opensearch.common.collect.Set.of("analyzer", "similarity");
+        return Set.of("analyzer", "similarity");
     }
 
     @Override
diff --git a/plugins/mapper-murmur3/src/test/java/org/opensearch/index/mapper/murmur3/Murmur3FieldMapperTests.java b/plugins/mapper-murmur3/src/test/java/org/opensearch/index/mapper/murmur3/Murmur3FieldMapperTests.java
index 5cfbc0cde1050..8bf5b86a06b39 100644
--- a/plugins/mapper-murmur3/src/test/java/org/opensearch/index/mapper/murmur3/Murmur3FieldMapperTests.java
+++ b/plugins/mapper-murmur3/src/test/java/org/opensearch/index/mapper/murmur3/Murmur3FieldMapperTests.java
@@ -45,6 +45,7 @@
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.List;
 
 public class Murmur3FieldMapperTests extends MapperTestCase {
 
@@ -55,7 +56,7 @@ protected void writeFieldValue(XContentBuilder builder) throws IOException {
 
     @Override
     protected Collection<? extends Plugin> getPlugins() {
-        return org.opensearch.common.collect.List.of(new MapperMurmur3Plugin());
+        return List.of(new MapperMurmur3Plugin());
     }
 
     @Override
diff --git a/plugins/repository-azure/build.gradle b/plugins/repository-azure/build.gradle
index 0105c32669ad8..89ea405464987 100644
--- a/plugins/repository-azure/build.gradle
+++ b/plugins/repository-azure/build.gradle
@@ -45,7 +45,7 @@ opensearchplugin {
 
 dependencies {
   api 'com.azure:azure-core:1.34.0'
-  api 'com.azure:azure-storage-common:12.19.3'
+  api 'com.azure:azure-storage-common:12.20.0'
   api 'com.azure:azure-core-http-netty:1.12.8'
   api "io.netty:netty-codec-dns:${versions.netty}"
   api "io.netty:netty-codec-socks:${versions.netty}"
@@ -57,9 +57,9 @@ dependencies {
   api 'com.azure:azure-storage-blob:12.15.0'
   api 'org.reactivestreams:reactive-streams:1.0.3'
   api 'io.projectreactor:reactor-core:3.4.18'
-  api 'io.projectreactor.netty:reactor-netty:1.1.3'
+  api 'io.projectreactor.netty:reactor-netty:1.1.4'
   api 'io.projectreactor.netty:reactor-netty-core:1.0.24'
-  api 'io.projectreactor.netty:reactor-netty-http:1.1.3'
+  api 'io.projectreactor.netty:reactor-netty-http:1.1.4'
   api "org.slf4j:slf4j-api:${versions.slf4j}"
   api "com.fasterxml.jackson.core:jackson-annotations:${versions.jackson}"
   api "com.fasterxml.jackson.core:jackson-databind:${versions.jackson_databind}"
diff --git a/plugins/repository-azure/licenses/azure-storage-common-12.19.3.jar.sha1 b/plugins/repository-azure/licenses/azure-storage-common-12.19.3.jar.sha1
deleted file mode 100644
index c22aa05ad5258..0000000000000
--- a/plugins/repository-azure/licenses/azure-storage-common-12.19.3.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-3e30b1be613815b10ea8d2cfa39f560aaeef5f0d
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/azure-storage-common-12.20.0.jar.sha1 b/plugins/repository-azure/licenses/azure-storage-common-12.20.0.jar.sha1
new file mode 100644
index 0000000000000..1fd3f8066411d
--- /dev/null
+++ b/plugins/repository-azure/licenses/azure-storage-common-12.20.0.jar.sha1
@@ -0,0 +1 @@
+69b962bbeea787c6aca83115472791aacc2ae94c
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/netty-codec-dns-4.1.87.Final.jar.sha1 b/plugins/repository-azure/licenses/netty-codec-dns-4.1.87.Final.jar.sha1
deleted file mode 100644
index ea9c36f36b988..0000000000000
--- a/plugins/repository-azure/licenses/netty-codec-dns-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-092ec0019d4e72c1305f4357694c4831aade60ce
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/netty-codec-dns-4.1.90.Final.jar.sha1 b/plugins/repository-azure/licenses/netty-codec-dns-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..3ef0c5df26b85
--- /dev/null
+++ b/plugins/repository-azure/licenses/netty-codec-dns-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+ebf5da8e6edf783d069d9aca346ff46c55772de6
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/netty-codec-http2-4.1.87.Final.jar.sha1 b/plugins/repository-azure/licenses/netty-codec-http2-4.1.87.Final.jar.sha1
deleted file mode 100644
index da15720c2d0e1..0000000000000
--- a/plugins/repository-azure/licenses/netty-codec-http2-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-72b756ff290d782c9ebb36db7d42ee272270c0b4
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/netty-codec-http2-4.1.90.Final.jar.sha1 b/plugins/repository-azure/licenses/netty-codec-http2-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..64caa309f2c05
--- /dev/null
+++ b/plugins/repository-azure/licenses/netty-codec-http2-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+ea3be877ea976b3d71e1a872958d32854b24db66
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/netty-codec-socks-4.1.87.Final.jar.sha1 b/plugins/repository-azure/licenses/netty-codec-socks-4.1.87.Final.jar.sha1
deleted file mode 100644
index 5bd83f816a9e4..0000000000000
--- a/plugins/repository-azure/licenses/netty-codec-socks-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-109027470b72d56914d76154e947f9bd5844bb9b
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/netty-codec-socks-4.1.90.Final.jar.sha1 b/plugins/repository-azure/licenses/netty-codec-socks-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..2738db8a6710a
--- /dev/null
+++ b/plugins/repository-azure/licenses/netty-codec-socks-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+7397535a4e03d2f74c71aa2282eb7a2760ffc37b
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/netty-handler-proxy-4.1.87.Final.jar.sha1 b/plugins/repository-azure/licenses/netty-handler-proxy-4.1.87.Final.jar.sha1
deleted file mode 100644
index 226ea309ac472..0000000000000
--- a/plugins/repository-azure/licenses/netty-handler-proxy-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-8079f16d6209e10f5d3a09522e7aa9ffb217e17e
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/netty-handler-proxy-4.1.90.Final.jar.sha1 b/plugins/repository-azure/licenses/netty-handler-proxy-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..60bde875d0faf
--- /dev/null
+++ b/plugins/repository-azure/licenses/netty-handler-proxy-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+6ab526a43a14f7796434fa6a705c34201603235f
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/netty-resolver-dns-4.1.87.Final.jar.sha1 b/plugins/repository-azure/licenses/netty-resolver-dns-4.1.87.Final.jar.sha1
deleted file mode 100644
index 39d59cb45eed2..0000000000000
--- a/plugins/repository-azure/licenses/netty-resolver-dns-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-a40442ff2afaf73d7ddc1d75d7e86814ef04f980
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/netty-resolver-dns-4.1.90.Final.jar.sha1 b/plugins/repository-azure/licenses/netty-resolver-dns-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..6124f27a050e0
--- /dev/null
+++ b/plugins/repository-azure/licenses/netty-resolver-dns-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+c9e6762805fe1bc854352dbc8020226f38674bce
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/netty-transport-native-unix-common-4.1.87.Final.jar.sha1 b/plugins/repository-azure/licenses/netty-transport-native-unix-common-4.1.87.Final.jar.sha1
deleted file mode 100644
index 4fb195e5f08f6..0000000000000
--- a/plugins/repository-azure/licenses/netty-transport-native-unix-common-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-4bf8308dc7d6ba2570681eaeddb16f8d1196b438
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/netty-transport-native-unix-common-4.1.90.Final.jar.sha1 b/plugins/repository-azure/licenses/netty-transport-native-unix-common-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..5f954b2595927
--- /dev/null
+++ b/plugins/repository-azure/licenses/netty-transport-native-unix-common-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+e42282002cf22105e7e993651aead231246d0220
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/reactor-netty-1.1.3.jar.sha1 b/plugins/repository-azure/licenses/reactor-netty-1.1.3.jar.sha1
deleted file mode 100644
index 00cb9fe0edf44..0000000000000
--- a/plugins/repository-azure/licenses/reactor-netty-1.1.3.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-2745c13811d82b7c57d4ca52764bbaab83e3e2e2
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/reactor-netty-1.1.4.jar.sha1 b/plugins/repository-azure/licenses/reactor-netty-1.1.4.jar.sha1
new file mode 100644
index 0000000000000..ab76deb3bc1f1
--- /dev/null
+++ b/plugins/repository-azure/licenses/reactor-netty-1.1.4.jar.sha1
@@ -0,0 +1 @@
+1b66183ba316fbbd2d212eb9e9a3ba060ba557b0
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/reactor-netty-http-1.1.3.jar.sha1 b/plugins/repository-azure/licenses/reactor-netty-http-1.1.3.jar.sha1
deleted file mode 100644
index fda433830ce35..0000000000000
--- a/plugins/repository-azure/licenses/reactor-netty-http-1.1.3.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-ddebf6e059e10315e9a53417289c98745a8fc7a7
\ No newline at end of file
diff --git a/plugins/repository-azure/licenses/reactor-netty-http-1.1.4.jar.sha1 b/plugins/repository-azure/licenses/reactor-netty-http-1.1.4.jar.sha1
new file mode 100644
index 0000000000000..7848fcdd8f5cb
--- /dev/null
+++ b/plugins/repository-azure/licenses/reactor-netty-http-1.1.4.jar.sha1
@@ -0,0 +1 @@
+ca8b2f1b23e4593577e0f570e04bb80cd29ce1e3
\ No newline at end of file
diff --git a/plugins/repository-azure/src/main/java/org/opensearch/repositories/azure/AzureBlobStore.java b/plugins/repository-azure/src/main/java/org/opensearch/repositories/azure/AzureBlobStore.java
index b540dd83c95a2..060ffdda79196 100644
--- a/plugins/repository-azure/src/main/java/org/opensearch/repositories/azure/AzureBlobStore.java
+++ b/plugins/repository-azure/src/main/java/org/opensearch/repositories/azure/AzureBlobStore.java
@@ -442,7 +442,7 @@ private static class Stats {
         private final AtomicLong putBlockListOperations = new AtomicLong();
 
         private Map<String, Long> toMap() {
-            return org.opensearch.common.collect.Map.of(
+            return Map.of(
                 "GetBlob",
                 getOperations.get(),
                 "ListBlobs",
diff --git a/plugins/repository-azure/src/main/java/org/opensearch/repositories/azure/AzureRepository.java b/plugins/repository-azure/src/main/java/org/opensearch/repositories/azure/AzureRepository.java
index a7799fef475f3..3e71c389e2fb0 100644
--- a/plugins/repository-azure/src/main/java/org/opensearch/repositories/azure/AzureRepository.java
+++ b/plugins/repository-azure/src/main/java/org/opensearch/repositories/azure/AzureRepository.java
@@ -150,7 +150,7 @@ public AzureRepository(
     }
 
     private static Map<String, String> buildLocation(RepositoryMetadata metadata) {
-        return org.opensearch.common.collect.Map.of(
+        return Map.of(
             "base_path",
             Repository.BASE_PATH_SETTING.get(metadata.settings()),
             "container",
diff --git a/plugins/repository-gcs/src/main/java/org/opensearch/repositories/gcs/GoogleCloudStorageHttpStatsCollector.java b/plugins/repository-gcs/src/main/java/org/opensearch/repositories/gcs/GoogleCloudStorageHttpStatsCollector.java
index 7375d4edb9030..2f48de94a4830 100644
--- a/plugins/repository-gcs/src/main/java/org/opensearch/repositories/gcs/GoogleCloudStorageHttpStatsCollector.java
+++ b/plugins/repository-gcs/src/main/java/org/opensearch/repositories/gcs/GoogleCloudStorageHttpStatsCollector.java
@@ -36,8 +36,8 @@
 import com.google.api.client.http.HttpRequest;
 import com.google.api.client.http.HttpResponse;
 import com.google.api.client.http.HttpResponseInterceptor;
-import org.opensearch.common.collect.List;
 
+import java.util.List;
 import java.util.Locale;
 import java.util.function.Consumer;
 import java.util.function.Function;
diff --git a/plugins/repository-gcs/src/main/java/org/opensearch/repositories/gcs/GoogleCloudStorageRepository.java b/plugins/repository-gcs/src/main/java/org/opensearch/repositories/gcs/GoogleCloudStorageRepository.java
index 909dc066a493b..2369248f7a244 100644
--- a/plugins/repository-gcs/src/main/java/org/opensearch/repositories/gcs/GoogleCloudStorageRepository.java
+++ b/plugins/repository-gcs/src/main/java/org/opensearch/repositories/gcs/GoogleCloudStorageRepository.java
@@ -115,12 +115,7 @@ class GoogleCloudStorageRepository extends MeteredBlobStoreRepository {
     }
 
     private static Map<String, String> buildLocation(RepositoryMetadata metadata) {
-        return org.opensearch.common.collect.Map.of(
-            "base_path",
-            BASE_PATH.get(metadata.settings()),
-            "bucket",
-            getSetting(BUCKET, metadata)
-        );
+        return Map.of("base_path", BASE_PATH.get(metadata.settings()), "bucket", getSetting(BUCKET, metadata));
     }
 
     @Override
diff --git a/plugins/repository-hdfs/build.gradle b/plugins/repository-hdfs/build.gradle
index 3712b9dbc6caa..d2f8eee79dfdd 100644
--- a/plugins/repository-hdfs/build.gradle
+++ b/plugins/repository-hdfs/build.gradle
@@ -69,7 +69,7 @@ dependencies {
   api 'org.apache.avro:avro:1.11.1'
   api 'com.google.code.gson:gson:2.10.1'
   runtimeOnly "com.google.guava:guava:${versions.guava}"
-  api 'com.google.protobuf:protobuf-java:3.22.0'
+  api 'com.google.protobuf:protobuf-java:3.22.2'
   api "commons-logging:commons-logging:${versions.commonslogging}"
   api 'commons-cli:commons-cli:1.2'
   api "commons-codec:commons-codec:${versions.commonscodec}"
@@ -82,7 +82,7 @@ dependencies {
   api 'javax.servlet:servlet-api:2.5'
   api "org.slf4j:slf4j-api:${versions.slf4j}"
   api "org.apache.logging.log4j:log4j-slf4j-impl:${versions.log4j}"
-  api 'net.minidev:json-smart:2.4.7'
+  api 'net.minidev:json-smart:2.4.10'
   api "io.netty:netty-all:${versions.netty}"
   implementation "com.fasterxml.woodstox:woodstox-core:${versions.woodstox}"
   implementation 'org.codehaus.woodstox:stax2-api:4.2.1'
diff --git a/plugins/repository-hdfs/licenses/json-smart-2.4.10.jar.sha1 b/plugins/repository-hdfs/licenses/json-smart-2.4.10.jar.sha1
new file mode 100644
index 0000000000000..faac861f60a28
--- /dev/null
+++ b/plugins/repository-hdfs/licenses/json-smart-2.4.10.jar.sha1
@@ -0,0 +1 @@
+91cb329e9424bf32131eeb1ce2d17bf31b9899bc
\ No newline at end of file
diff --git a/plugins/repository-hdfs/licenses/json-smart-2.4.7.jar.sha1 b/plugins/repository-hdfs/licenses/json-smart-2.4.7.jar.sha1
deleted file mode 100644
index 16f9a4431485a..0000000000000
--- a/plugins/repository-hdfs/licenses/json-smart-2.4.7.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-8d7f4c1530c07c54930935f3da85f48b83b3c109
\ No newline at end of file
diff --git a/plugins/repository-hdfs/licenses/netty-all-4.1.87.Final.jar.sha1 b/plugins/repository-hdfs/licenses/netty-all-4.1.87.Final.jar.sha1
deleted file mode 100644
index 8dcb64ecfdf24..0000000000000
--- a/plugins/repository-hdfs/licenses/netty-all-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-39de92ea74a05da937343695f780e59addb8b8ea
\ No newline at end of file
diff --git a/plugins/repository-hdfs/licenses/netty-all-4.1.90.Final.jar.sha1 b/plugins/repository-hdfs/licenses/netty-all-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..829204d91b994
--- /dev/null
+++ b/plugins/repository-hdfs/licenses/netty-all-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+0fb2bac7d106f8db84b111202bfb1c68a1aa89b8
\ No newline at end of file
diff --git a/plugins/repository-hdfs/licenses/protobuf-java-3.22.0.jar.sha1 b/plugins/repository-hdfs/licenses/protobuf-java-3.22.0.jar.sha1
deleted file mode 100644
index 4255cb52bf49c..0000000000000
--- a/plugins/repository-hdfs/licenses/protobuf-java-3.22.0.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-aa58e31e88e9974452f0498e237532df5732257a
\ No newline at end of file
diff --git a/plugins/repository-hdfs/licenses/protobuf-java-3.22.2.jar.sha1 b/plugins/repository-hdfs/licenses/protobuf-java-3.22.2.jar.sha1
new file mode 100644
index 0000000000000..80feeec023e7b
--- /dev/null
+++ b/plugins/repository-hdfs/licenses/protobuf-java-3.22.2.jar.sha1
@@ -0,0 +1 @@
+fdee98b8f6abab73f146a4edb4c09e56f8278d03
\ No newline at end of file
diff --git a/plugins/repository-hdfs/src/test/java/org/opensearch/repositories/hdfs/HaHdfsFailoverTestSuiteIT.java b/plugins/repository-hdfs/src/test/java/org/opensearch/repositories/hdfs/HaHdfsFailoverTestSuiteIT.java
index e12b24f27dcdc..d0b63f17e3887 100644
--- a/plugins/repository-hdfs/src/test/java/org/opensearch/repositories/hdfs/HaHdfsFailoverTestSuiteIT.java
+++ b/plugins/repository-hdfs/src/test/java/org/opensearch/repositories/hdfs/HaHdfsFailoverTestSuiteIT.java
@@ -75,9 +75,9 @@ public void testHAFailoverWithRepository() throws Exception {
         String nn2Port = "10002";
         if (ports.length() > 0) {
             final Path path = PathUtils.get(ports);
-            final List<String> lines = AccessController.doPrivileged(
-                (PrivilegedExceptionAction<List<String>>) () -> { return Files.readAllLines(path); }
-            );
+            final List<String> lines = AccessController.doPrivileged((PrivilegedExceptionAction<List<String>>) () -> {
+                return Files.readAllLines(path);
+            });
             nn1Port = lines.get(0);
             nn2Port = lines.get(1);
         }
diff --git a/plugins/repository-hdfs/src/test/resources/rest-api-spec/test/hdfs_repository/30_snapshot.yml b/plugins/repository-hdfs/src/test/resources/rest-api-spec/test/hdfs_repository/30_snapshot.yml
index fbe0e0a8b0066..7e76024dd2368 100644
--- a/plugins/repository-hdfs/src/test/resources/rest-api-spec/test/hdfs_repository/30_snapshot.yml
+++ b/plugins/repository-hdfs/src/test/resources/rest-api-spec/test/hdfs_repository/30_snapshot.yml
@@ -36,7 +36,7 @@
   - match: { snapshot.shards.failed : 0 }
 
   # Remove our snapshot
-  - do: 
+  - do:
       snapshot.delete:
         repository: test_snapshot_repository
         snapshot: test_snapshot
diff --git a/plugins/repository-hdfs/src/test/resources/rest-api-spec/test/hdfs_repository/30_snapshot_get.yml b/plugins/repository-hdfs/src/test/resources/rest-api-spec/test/hdfs_repository/30_snapshot_get.yml
index f38f4783b195b..3e61ef62f2a7d 100644
--- a/plugins/repository-hdfs/src/test/resources/rest-api-spec/test/hdfs_repository/30_snapshot_get.yml
+++ b/plugins/repository-hdfs/src/test/resources/rest-api-spec/test/hdfs_repository/30_snapshot_get.yml
@@ -59,7 +59,7 @@
   - match: { snapshots.0.snapshot : test_snapshot_get }
 
   # Remove our snapshot
-  - do: 
+  - do:
       snapshot.delete:
         repository: test_snapshot_get_repository
         snapshot: test_snapshot_get
diff --git a/plugins/repository-s3/src/main/java/org/opensearch/repositories/s3/S3Repository.java b/plugins/repository-s3/src/main/java/org/opensearch/repositories/s3/S3Repository.java
index c8377949a6842..9cc97244cae46 100644
--- a/plugins/repository-s3/src/main/java/org/opensearch/repositories/s3/S3Repository.java
+++ b/plugins/repository-s3/src/main/java/org/opensearch/repositories/s3/S3Repository.java
@@ -310,12 +310,7 @@ class S3Repository extends MeteredBlobStoreRepository {
     }
 
     private static Map<String, String> buildLocation(RepositoryMetadata metadata) {
-        return org.opensearch.common.collect.Map.of(
-            "base_path",
-            BASE_PATH_SETTING.get(metadata.settings()),
-            "bucket",
-            BUCKET_SETTING.get(metadata.settings())
-        );
+        return Map.of("base_path", BASE_PATH_SETTING.get(metadata.settings()), "bucket", BUCKET_SETTING.get(metadata.settings()));
     }
 
     /**
diff --git a/plugins/transport-nio/build.gradle b/plugins/transport-nio/build.gradle
index 5ebb2a835782a..8a6a6a334e1a9 100644
--- a/plugins/transport-nio/build.gradle
+++ b/plugins/transport-nio/build.gradle
@@ -65,7 +65,7 @@ thirdPartyAudit {
     'com.aayushatharva.brotli4j.encoder.Encoder',
     'com.aayushatharva.brotli4j.encoder.Encoder$Mode',
     'com.aayushatharva.brotli4j.encoder.Encoder$Parameters',
-    
+
     // from io.netty.handler.codec.protobuf.ProtobufDecoder (netty)
     'com.google.protobuf.ExtensionRegistry',
     'com.google.protobuf.MessageLite$Builder',
diff --git a/plugins/transport-nio/licenses/netty-buffer-4.1.87.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-buffer-4.1.87.Final.jar.sha1
deleted file mode 100644
index 8350f48acdb54..0000000000000
--- a/plugins/transport-nio/licenses/netty-buffer-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-8942174141fb0586e7fffefc8ae48e1458293696
\ No newline at end of file
diff --git a/plugins/transport-nio/licenses/netty-buffer-4.1.90.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-buffer-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..67604d11c1eca
--- /dev/null
+++ b/plugins/transport-nio/licenses/netty-buffer-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+937eb60c19c5f5c1326b96123c9ec3d33238d4d5
\ No newline at end of file
diff --git a/plugins/transport-nio/licenses/netty-codec-4.1.87.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-codec-4.1.87.Final.jar.sha1
deleted file mode 100644
index 9a494c68b7afb..0000000000000
--- a/plugins/transport-nio/licenses/netty-codec-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-d7ab7363f736114e6324ccf802d094529b30b8d8
\ No newline at end of file
diff --git a/plugins/transport-nio/licenses/netty-codec-4.1.90.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-codec-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..c8fb04a021807
--- /dev/null
+++ b/plugins/transport-nio/licenses/netty-codec-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+9992a22c82e18b8fd4f34989535f3e504e55aa37
\ No newline at end of file
diff --git a/plugins/transport-nio/licenses/netty-codec-http-4.1.87.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-codec-http-4.1.87.Final.jar.sha1
deleted file mode 100644
index 115657578cf80..0000000000000
--- a/plugins/transport-nio/licenses/netty-codec-http-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-3230e95d6832ee4306fe1ca774c7bcecf1da4b28
\ No newline at end of file
diff --git a/plugins/transport-nio/licenses/netty-codec-http-4.1.90.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-codec-http-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..861599ce1d1d2
--- /dev/null
+++ b/plugins/transport-nio/licenses/netty-codec-http-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+19bbcd46f8ee0d118486f98eff22fe665b9689e5
\ No newline at end of file
diff --git a/plugins/transport-nio/licenses/netty-common-4.1.87.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-common-4.1.87.Final.jar.sha1
deleted file mode 100644
index 066550b9e0135..0000000000000
--- a/plugins/transport-nio/licenses/netty-common-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-3e7e80dd6e604144781fcb859b79cfe8d3730079
\ No newline at end of file
diff --git a/plugins/transport-nio/licenses/netty-common-4.1.90.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-common-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..afb531805329e
--- /dev/null
+++ b/plugins/transport-nio/licenses/netty-common-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+43597a09382c6ae2bef469a9b3a41e8a17850638
\ No newline at end of file
diff --git a/plugins/transport-nio/licenses/netty-handler-4.1.87.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-handler-4.1.87.Final.jar.sha1
deleted file mode 100644
index 0923602100814..0000000000000
--- a/plugins/transport-nio/licenses/netty-handler-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-2bd97491c22ebea4670c00f1bd5dbf65a8a1cfe7
\ No newline at end of file
diff --git a/plugins/transport-nio/licenses/netty-handler-4.1.90.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-handler-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..c98bfb52393d6
--- /dev/null
+++ b/plugins/transport-nio/licenses/netty-handler-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+64f6946ce4d9189cec5341d3f5f86ac5653099b5
\ No newline at end of file
diff --git a/plugins/transport-nio/licenses/netty-resolver-4.1.87.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-resolver-4.1.87.Final.jar.sha1
deleted file mode 100644
index 4465a47bd49fb..0000000000000
--- a/plugins/transport-nio/licenses/netty-resolver-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-eaa964e16a67914c8d9b814d29a4b969635d72a0
\ No newline at end of file
diff --git a/plugins/transport-nio/licenses/netty-resolver-4.1.90.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-resolver-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..b92177828aa56
--- /dev/null
+++ b/plugins/transport-nio/licenses/netty-resolver-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+47c415d8c83f08b820ba00e6497a6cf19dd0155f
\ No newline at end of file
diff --git a/plugins/transport-nio/licenses/netty-transport-4.1.87.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-transport-4.1.87.Final.jar.sha1
deleted file mode 100644
index dcb49c515e460..0000000000000
--- a/plugins/transport-nio/licenses/netty-transport-4.1.87.Final.jar.sha1
+++ /dev/null
@@ -1 +0,0 @@
-30c78c8ced3417f35e2a55f7533dc2bb43fef2aa
\ No newline at end of file
diff --git a/plugins/transport-nio/licenses/netty-transport-4.1.90.Final.jar.sha1 b/plugins/transport-nio/licenses/netty-transport-4.1.90.Final.jar.sha1
new file mode 100644
index 0000000000000..c7a77dbf6aaa8
--- /dev/null
+++ b/plugins/transport-nio/licenses/netty-transport-4.1.90.Final.jar.sha1
@@ -0,0 +1 @@
+82d68da212f62b076c763f5efa9b072d2abc018f
\ No newline at end of file
diff --git a/qa/logging-config/src/test/java/org/opensearch/common/logging/OpenSearchJsonLayoutTests.java b/qa/logging-config/src/test/java/org/opensearch/common/logging/OpenSearchJsonLayoutTests.java
index 6639d53c9c879..0a8bd46ac96f3 100644
--- a/qa/logging-config/src/test/java/org/opensearch/common/logging/OpenSearchJsonLayoutTests.java
+++ b/qa/logging-config/src/test/java/org/opensearch/common/logging/OpenSearchJsonLayoutTests.java
@@ -66,6 +66,46 @@ public void testLayout() {
                 "%exceptionAsJson }" + System.lineSeparator()));
     }
 
+    public void testWithMaxMessageLengthLayout() {
+        OpenSearchJsonLayout server = OpenSearchJsonLayout.newBuilder()
+            .setType("server")
+            .setMaxMessageLength(42)
+            .build();
+        String conversionPattern = server.getPatternLayout().getConversionPattern();
+
+        assertThat(conversionPattern, Matchers.equalTo(
+            "{" +
+                "\"type\": \"server\", " +
+                "\"timestamp\": \"%d{yyyy-MM-dd'T'HH:mm:ss,SSSZZ}\", " +
+                "\"level\": \"%p\", " +
+                "\"component\": \"%c{1.}\", " +
+                "\"cluster.name\": \"${sys:opensearch.logs.cluster_name}\", " +
+                "\"node.name\": \"%node_name\", " +
+                "\"message\": \"%notEmpty{%enc{%marker}{JSON} }%enc{%.-42m}{JSON}\"" +
+                "%notEmpty{, %node_and_cluster_id }" +
+                "%exceptionAsJson }" + System.lineSeparator()));
+    }
+
+    public void testWithUnrestrictedMaxMessageLengthLayout() {
+        OpenSearchJsonLayout server = OpenSearchJsonLayout.newBuilder()
+            .setType("server")
+            .setMaxMessageLength(0)
+            .build();
+        String conversionPattern = server.getPatternLayout().getConversionPattern();
+
+        assertThat(conversionPattern, Matchers.equalTo(
+            "{" +
+                "\"type\": \"server\", " +
+                "\"timestamp\": \"%d{yyyy-MM-dd'T'HH:mm:ss,SSSZZ}\", " +
+                "\"level\": \"%p\", " +
+                "\"component\": \"%c{1.}\", " +
+                "\"cluster.name\": \"${sys:opensearch.logs.cluster_name}\", " +
+                "\"node.name\": \"%node_name\", " +
+                "\"message\": \"%notEmpty{%enc{%marker}{JSON} }%enc{%m}{JSON}\"" +
+                "%notEmpty{, %node_and_cluster_id }" +
+                "%exceptionAsJson }" + System.lineSeparator()));
+    }
+
     public void testLayoutWithAdditionalFields() {
         OpenSearchJsonLayout server = OpenSearchJsonLayout.newBuilder()
                                           .setType("server")
diff --git a/qa/os/src/test/java/org/opensearch/packaging/test/ArchiveTests.java b/qa/os/src/test/java/org/opensearch/packaging/test/ArchiveTests.java
index 898ea12b6a6c3..29e40a4e179cb 100644
--- a/qa/os/src/test/java/org/opensearch/packaging/test/ArchiveTests.java
+++ b/qa/os/src/test/java/org/opensearch/packaging/test/ArchiveTests.java
@@ -328,7 +328,7 @@ public void test54ForceBundledJdkEmptyJavaHome() throws Exception {
     public void test70CustomPathConfAndJvmOptions() throws Exception {
 
         withCustomConfig(tempConf -> {
-            final List<String> jvmOptions = org.opensearch.common.collect.List.of("-Xms512m", "-Xmx512m", "-Dlog4j2.disable.jmx=true");
+            final List<String> jvmOptions = List.of("-Xms512m", "-Xmx512m", "-Dlog4j2.disable.jmx=true");
             Files.write(tempConf.resolve("jvm.options"), jvmOptions, CREATE, APPEND);
 
             sh.getEnv().put("OPENSEARCH_JAVA_OPTS", "-XX:-UseCompressedOops");
diff --git a/qa/os/src/test/java/org/opensearch/packaging/util/FileUtils.java b/qa/os/src/test/java/org/opensearch/packaging/util/FileUtils.java
index aa52c3325bee5..d7005a17926ad 100644
--- a/qa/os/src/test/java/org/opensearch/packaging/util/FileUtils.java
+++ b/qa/os/src/test/java/org/opensearch/packaging/util/FileUtils.java
@@ -83,7 +83,7 @@ public class FileUtils {
     public static List<Path> lsGlob(Path directory, String glob) {
         List<Path> paths = new ArrayList<>();
         if (Files.exists(directory) == false) {
-            return org.opensearch.common.collect.List.of();
+            return List.of();
         }
         try (DirectoryStream<Path> stream = Files.newDirectoryStream(directory, glob)) {
 
diff --git a/qa/os/src/test/java/org/opensearch/packaging/util/Packages.java b/qa/os/src/test/java/org/opensearch/packaging/util/Packages.java
index cea03a0b6fe70..b80ae422bda9a 100644
--- a/qa/os/src/test/java/org/opensearch/packaging/util/Packages.java
+++ b/qa/os/src/test/java/org/opensearch/packaging/util/Packages.java
@@ -322,7 +322,7 @@ private enum PackageManagerCommand {
         REMOVE
     }
 
-    private static Map<PackageManagerCommand, String> RPM_OPTIONS = org.opensearch.common.collect.Map.of(
+    private static Map<PackageManagerCommand, String> RPM_OPTIONS = Map.of(
         PackageManagerCommand.QUERY,
         "-qe",
         PackageManagerCommand.INSTALL,
@@ -335,7 +335,7 @@ private enum PackageManagerCommand {
         "-e"
     );
 
-    private static Map<PackageManagerCommand, String> DEB_OPTIONS = org.opensearch.common.collect.Map.of(
+    private static Map<PackageManagerCommand, String> DEB_OPTIONS = Map.of(
         PackageManagerCommand.QUERY,
         "-s",
         PackageManagerCommand.INSTALL,
diff --git a/qa/smoke-test-http/src/test/java/org/opensearch/http/SystemIndexRestIT.java b/qa/smoke-test-http/src/test/java/org/opensearch/http/SystemIndexRestIT.java
index e687e5eb8a151..9f2d686251947 100644
--- a/qa/smoke-test-http/src/test/java/org/opensearch/http/SystemIndexRestIT.java
+++ b/qa/smoke-test-http/src/test/java/org/opensearch/http/SystemIndexRestIT.java
@@ -157,7 +157,7 @@ public List<RestHandler> getRestHandlers(Settings settings, RestController restC
                                                  IndexScopedSettings indexScopedSettings, SettingsFilter settingsFilter,
                                                  IndexNameExpressionResolver indexNameExpressionResolver,
                                                  Supplier<DiscoveryNodes> nodesInCluster) {
-            return org.opensearch.common.collect.List.of(new AddDocRestHandler());
+            return List.of(new AddDocRestHandler());
         }
 
         @Override
@@ -178,7 +178,7 @@ public String getName() {
 
             @Override
             public List<Route> routes() {
-                return org.opensearch.common.collect.List.of(new Route(RestRequest.Method.POST, "/_sys_index_test/add_doc/{id}"));
+                return List.of(new Route(RestRequest.Method.POST, "/_sys_index_test/add_doc/{id}"));
             }
 
             @Override
@@ -186,7 +186,7 @@ protected RestChannelConsumer prepareRequest(RestRequest request, NodeClient cli
                 IndexRequest indexRequest = new IndexRequest(SYSTEM_INDEX_NAME);
                 indexRequest.id(request.param("id"));
                 indexRequest.setRefreshPolicy(WriteRequest.RefreshPolicy.IMMEDIATE);
-                indexRequest.source(org.opensearch.common.collect.Map.of("some_field", "some_value"));
+                indexRequest.source(Map.of("some_field", "some_value"));
                 return channel -> client.index(indexRequest,
                     new RestStatusToXContentListener<>(channel, r -> r.getLocation(indexRequest.routing())));
             }
diff --git a/rest-api-spec/src/main/resources/rest-api-spec/api/cat.segment_replication.json b/rest-api-spec/src/main/resources/rest-api-spec/api/cat.segment_replication.json
index 0b1c65e551d63..a815cd5b1101b 100644
--- a/rest-api-spec/src/main/resources/rest-api-spec/api/cat.segment_replication.json
+++ b/rest-api-spec/src/main/resources/rest-api-spec/api/cat.segment_replication.json
@@ -37,11 +37,6 @@
         "description":"If `true`, the response only includes ongoing segment replication events",
         "default":false
       },
-      "completed_only":{
-        "type":"boolean",
-        "description":"If `true`, the response only includes latest completed segment replication events",
-        "default":false
-      },
       "bytes":{
         "type":"enum",
         "description":"The unit in which to display byte values",
diff --git a/rest-api-spec/src/main/resources/rest-api-spec/test/cat.cluster_manager/10_basic.yml b/rest-api-spec/src/main/resources/rest-api-spec/test/cat.cluster_manager/10_basic.yml
index b0f1c81b56a0e..6354c751aa5f3 100644
--- a/rest-api-spec/src/main/resources/rest-api-spec/test/cat.cluster_manager/10_basic.yml
+++ b/rest-api-spec/src/main/resources/rest-api-spec/test/cat.cluster_manager/10_basic.yml
@@ -20,7 +20,7 @@ setup:
             host     .+ \n
             ip       .+ \n
             node     .+ \n
-        
+
         $/
 
 ---
diff --git a/rest-api-spec/src/main/resources/rest-api-spec/test/cat.health/10_basic.yml b/rest-api-spec/src/main/resources/rest-api-spec/test/cat.health/10_basic.yml
index 0d945d01a6ddb..52b27837a61ac 100644
--- a/rest-api-spec/src/main/resources/rest-api-spec/test/cat.health/10_basic.yml
+++ b/rest-api-spec/src/main/resources/rest-api-spec/test/cat.health/10_basic.yml
@@ -9,9 +9,9 @@
         help: true
       node_selector:
         # Only send request to nodes in <2.0 versions, especially during ':qa:mixed-cluster:v1.x.x#mixedClusterTest'.
-        # Because YAML REST test takes the minimum OpenSearch version in the cluster to apply the filter in 'skip' section, 
+        # Because YAML REST test takes the minimum OpenSearch version in the cluster to apply the filter in 'skip' section,
         # see OpenSearchClientYamlSuiteTestCase#initAndResetContext() for detail.
-        # During 'mixedClusterTest', the cluster can be mixed with nodes in 1.x and 2.x versions, 
+        # During 'mixedClusterTest', the cluster can be mixed with nodes in 1.x and 2.x versions,
         # so node_selector is required, and only filtering version in 'skip' is not enough.
         version: "1.0.0 - 1.4.99"
 
@@ -61,7 +61,7 @@
                    pending_tasks .+ \n
                    max_task_wait_time .+ \n
                    active_shards_percent .+ \n
-      
+
                $/
 
 ---
diff --git a/rest-api-spec/src/main/resources/rest-api-spec/test/cluster.state/10_basic.yml b/rest-api-spec/src/main/resources/rest-api-spec/test/cluster.state/10_basic.yml
index fa973454cfba5..294f00bdd822b 100644
--- a/rest-api-spec/src/main/resources/rest-api-spec/test/cluster.state/10_basic.yml
+++ b/rest-api-spec/src/main/resources/rest-api-spec/test/cluster.state/10_basic.yml
@@ -17,18 +17,18 @@
 
   - is_true: cluster_uuid
   - is_true: master_node
-    
+
 ---
 "Get cluster state returns cluster_manager_node":
   - skip:
       version: " - 1.4.99"
       reason: "The metric cluster_manager_node is added to cluster state in version 2.0.0"
-      
+
   - do:
       cluster.state: {}
-      
+
   - set:
       cluster_manager_node: node_id
-      
+
   - match: {master_node: $node_id}
   - match: {cluster_manager_node: $node_id}
diff --git a/rest-api-spec/src/main/resources/rest-api-spec/test/indices.delete_alias/10_basic.yml b/rest-api-spec/src/main/resources/rest-api-spec/test/indices.delete_alias/10_basic.yml
index 74684901579a4..43a6f656c09c3 100644
--- a/rest-api-spec/src/main/resources/rest-api-spec/test/indices.delete_alias/10_basic.yml
+++ b/rest-api-spec/src/main/resources/rest-api-spec/test/indices.delete_alias/10_basic.yml
@@ -28,6 +28,6 @@
       indices.get_alias:
         index: testind
         name:  testali
-  
+
   - match: { 'status': 404 }
   - match: { 'error': 'alias [testali] missing' }
diff --git a/rest-api-spec/src/main/resources/rest-api-spec/test/indices.split/20_source_mapping.yml b/rest-api-spec/src/main/resources/rest-api-spec/test/indices.split/20_source_mapping.yml
index 69061c6d0fbd4..2c878157f468e 100644
--- a/rest-api-spec/src/main/resources/rest-api-spec/test/indices.split/20_source_mapping.yml
+++ b/rest-api-spec/src/main/resources/rest-api-spec/test/indices.split/20_source_mapping.yml
@@ -2,7 +2,7 @@
 "Split index ignores target template mapping":
   - skip:
       features: allowed_warnings
-  
+
   # create index
   - do:
       indices.create:
diff --git a/rest-api-spec/src/main/resources/rest-api-spec/test/pit/10_basic.yml b/rest-api-spec/src/main/resources/rest-api-spec/test/pit/10_basic.yml
index 84ff85f465f8b..9d1ee7571f2e2 100644
--- a/rest-api-spec/src/main/resources/rest-api-spec/test/pit/10_basic.yml
+++ b/rest-api-spec/src/main/resources/rest-api-spec/test/pit/10_basic.yml
@@ -138,5 +138,7 @@
   - match: {pits.0.successful: true }
 
   - do:
-      catch: missing
-      delete_all_pits: { }
+      delete_all_pits: {}
+
+  - match: {pits: []}
+  - length: {pits: 0}
diff --git a/server/src/internalClusterTest/java/org/opensearch/action/admin/cluster/node/tasks/TasksIT.java b/server/src/internalClusterTest/java/org/opensearch/action/admin/cluster/node/tasks/TasksIT.java
index 61059f83f0e77..62180412dbf98 100644
--- a/server/src/internalClusterTest/java/org/opensearch/action/admin/cluster/node/tasks/TasksIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/action/admin/cluster/node/tasks/TasksIT.java
@@ -510,14 +510,12 @@ public void taskExecutionStarted(Task task, Boolean closeableInvoked) {}
             if (index != null) {
                 index.join();
             }
-            assertBusy(
-                () -> {
-                    assertEquals(
-                        emptyList(),
-                        client().admin().cluster().prepareListTasks().setActions("indices:data/write/index*").get().getTasks()
-                    );
-                }
-            );
+            assertBusy(() -> {
+                assertEquals(
+                    emptyList(),
+                    client().admin().cluster().prepareListTasks().setActions("indices:data/write/index*").get().getTasks()
+                );
+            });
         }
     }
 
diff --git a/server/src/internalClusterTest/java/org/opensearch/action/admin/indices/datastream/DataStreamIndexTemplateIT.java b/server/src/internalClusterTest/java/org/opensearch/action/admin/indices/datastream/DataStreamIndexTemplateIT.java
index ed500d72c3787..08f7fb17e5164 100644
--- a/server/src/internalClusterTest/java/org/opensearch/action/admin/indices/datastream/DataStreamIndexTemplateIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/action/admin/indices/datastream/DataStreamIndexTemplateIT.java
@@ -8,8 +8,7 @@
 
 package org.opensearch.action.admin.indices.datastream;
 
-import org.opensearch.common.collect.List;
-
+import java.util.List;
 import java.util.concurrent.ExecutionException;
 
 import static org.hamcrest.Matchers.containsString;
diff --git a/server/src/internalClusterTest/java/org/opensearch/action/admin/indices/datastream/DataStreamUsageIT.java b/server/src/internalClusterTest/java/org/opensearch/action/admin/indices/datastream/DataStreamUsageIT.java
index 785be061135f0..46f23e40f0864 100644
--- a/server/src/internalClusterTest/java/org/opensearch/action/admin/indices/datastream/DataStreamUsageIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/action/admin/indices/datastream/DataStreamUsageIT.java
@@ -13,12 +13,12 @@
 import org.opensearch.action.index.IndexRequest;
 import org.opensearch.action.index.IndexResponse;
 import org.opensearch.cluster.metadata.DataStream;
-import org.opensearch.common.collect.List;
 import org.opensearch.common.xcontent.XContentFactory;
 import org.opensearch.common.xcontent.XContentType;
 import org.opensearch.rest.RestStatus;
 
 import java.util.Arrays;
+import java.util.List;
 import java.util.concurrent.ExecutionException;
 import java.util.stream.Collectors;
 
diff --git a/server/src/internalClusterTest/java/org/opensearch/action/bulk/BulkWithUpdatesIT.java b/server/src/internalClusterTest/java/org/opensearch/action/bulk/BulkWithUpdatesIT.java
index 4cf3f3564c8eb..53afa53de92f3 100644
--- a/server/src/internalClusterTest/java/org/opensearch/action/bulk/BulkWithUpdatesIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/action/bulk/BulkWithUpdatesIT.java
@@ -105,18 +105,9 @@ protected Map<String, Function<Map<String, Object>, Object>> pluginScripts() {
 
             scripts.put("ctx._source.field2 = 'value2'", vars -> srcScript(vars, source -> source.replace("field2", "value2")));
 
-            scripts.put(
-                "throw script exception on unknown var",
-                vars -> {
-                    throw new ScriptException(
-                        "message",
-                        null,
-                        Collections.emptyList(),
-                        "exception on unknown var",
-                        CustomScriptPlugin.NAME
-                    );
-                }
-            );
+            scripts.put("throw script exception on unknown var", vars -> {
+                throw new ScriptException("message", null, Collections.emptyList(), "exception on unknown var", CustomScriptPlugin.NAME);
+            });
 
             scripts.put("ctx.op = \"none\"", vars -> ((Map<String, Object>) vars.get("ctx")).put("op", "none"));
             scripts.put("ctx.op = \"delete\"", vars -> ((Map<String, Object>) vars.get("ctx")).put("op", "delete"));
diff --git a/server/src/internalClusterTest/java/org/opensearch/cluster/metadata/TemplateUpgradeServiceIT.java b/server/src/internalClusterTest/java/org/opensearch/cluster/metadata/TemplateUpgradeServiceIT.java
index babe228f544a9..ec617e88c249f 100644
--- a/server/src/internalClusterTest/java/org/opensearch/cluster/metadata/TemplateUpgradeServiceIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/cluster/metadata/TemplateUpgradeServiceIT.java
@@ -99,11 +99,9 @@ public Collection<Object> createComponents(
             IndexNameExpressionResolver expressionResolver,
             Supplier<RepositoriesService> repositoriesServiceSupplier
         ) {
-            clusterService.getClusterSettings()
-                .addSettingsUpdateConsumer(
-                    UPDATE_TEMPLATE_DUMMY_SETTING,
-                    integer -> { logger.debug("the template dummy setting was updated to {}", integer); }
-                );
+            clusterService.getClusterSettings().addSettingsUpdateConsumer(UPDATE_TEMPLATE_DUMMY_SETTING, integer -> {
+                logger.debug("the template dummy setting was updated to {}", integer);
+            });
             return super.createComponents(
                 client,
                 clusterService,
diff --git a/server/src/internalClusterTest/java/org/opensearch/cluster/routing/WeightedRoutingIT.java b/server/src/internalClusterTest/java/org/opensearch/cluster/routing/WeightedRoutingIT.java
index f18ee28a2de91..24ac2f2326931 100644
--- a/server/src/internalClusterTest/java/org/opensearch/cluster/routing/WeightedRoutingIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/cluster/routing/WeightedRoutingIT.java
@@ -15,6 +15,7 @@
 import org.opensearch.action.admin.cluster.shards.routing.weighted.put.ClusterPutWeightedRoutingResponse;
 import org.opensearch.cluster.health.ClusterHealthStatus;
 import org.opensearch.common.settings.Settings;
+import org.opensearch.discovery.ClusterManagerNotDiscoveredException;
 import org.opensearch.rest.RestStatus;
 import org.opensearch.snapshots.mockstore.MockRepository;
 import org.opensearch.test.OpenSearchIntegTestCase;
@@ -336,7 +337,6 @@ public void testGetWeightedRouting_ClusterManagerNotDiscovered() throws Exceptio
         ).admin().cluster().prepareGetWeightedRouting().setAwarenessAttribute("zone").setRequestLocal(true).get();
         assertEquals(weightedRouting, weightedRoutingResponse.weights());
         assertFalse(weightedRoutingResponse.getDiscoveredClusterManager());
-
         logger.info("--> network disruption is stopped");
         networkDisruption.stopDisrupting();
 
@@ -639,28 +639,18 @@ public void testClusterHealthResponseWithEnsureNodeWeighedInParam() throws Excep
         Thread.sleep(13000);
 
         // Check cluster health for weighed in node when cluster manager is not discovered, health check should
-        // return a response with 200 status code
-        nodeLocalHealth = client(nodes_in_zone_a.get(0)).admin()
-            .cluster()
-            .prepareHealth()
-            .setLocal(true)
-            .setEnsureNodeWeighedIn(true)
-            .get();
-        assertFalse(nodeLocalHealth.isTimedOut());
-        assertFalse(nodeLocalHealth.hasDiscoveredClusterManager());
+        // return a response with 503 status code
+        assertThrows(
+            ClusterManagerNotDiscoveredException.class,
+            () -> client(nodes_in_zone_a.get(0)).admin().cluster().prepareHealth().setLocal(true).setEnsureNodeWeighedIn(true).get()
+        );
 
         // Check cluster health for weighed away node when cluster manager is not discovered, health check should
-        // return a response with 200 status code with cluster manager discovered as false
-        // ensure_node_weighed_in is not executed if cluster manager is not discovered
-        nodeLocalHealth = client(nodes_in_zone_c.get(0)).admin()
-            .cluster()
-            .prepareHealth()
-            .setLocal(true)
-            .setEnsureNodeWeighedIn(true)
-            .get();
-        assertFalse(nodeLocalHealth.isTimedOut());
-        assertFalse(nodeLocalHealth.hasDiscoveredClusterManager());
-
+        // return a response with 503 status code
+        assertThrows(
+            ClusterManagerNotDiscoveredException.class,
+            () -> client(nodes_in_zone_c.get(0)).admin().cluster().prepareHealth().setLocal(true).setEnsureNodeWeighedIn(true).get()
+        );
         networkDisruption.stopDisrupting();
         Thread.sleep(1000);
 
diff --git a/server/src/internalClusterTest/java/org/opensearch/index/SegmentReplicationPressureIT.java b/server/src/internalClusterTest/java/org/opensearch/index/SegmentReplicationPressureIT.java
new file mode 100644
index 0000000000000..ee5150c97fb4f
--- /dev/null
+++ b/server/src/internalClusterTest/java/org/opensearch/index/SegmentReplicationPressureIT.java
@@ -0,0 +1,273 @@
+/*
+ * Copyright OpenSearch Contributors.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.index;
+
+import org.opensearch.action.bulk.BulkItemResponse;
+import org.opensearch.action.bulk.BulkRequest;
+import org.opensearch.action.bulk.BulkResponse;
+import org.opensearch.action.index.IndexRequest;
+import org.opensearch.cluster.metadata.IndexMetadata;
+import org.opensearch.common.UUIDs;
+import org.opensearch.common.lease.Releasable;
+import org.opensearch.common.settings.Settings;
+import org.opensearch.common.unit.TimeValue;
+import org.opensearch.common.util.concurrent.OpenSearchRejectedExecutionException;
+import org.opensearch.index.shard.IndexShard;
+import org.opensearch.indices.replication.SegmentReplicationBaseIT;
+import org.opensearch.plugins.Plugin;
+import org.opensearch.rest.RestStatus;
+import org.opensearch.test.OpenSearchIntegTestCase;
+import org.opensearch.test.transport.MockTransportService;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import static java.util.Arrays.asList;
+import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_NUMBER_OF_REPLICAS;
+import static org.opensearch.index.SegmentReplicationPressureService.MAX_INDEXING_CHECKPOINTS;
+import static org.opensearch.index.SegmentReplicationPressureService.MAX_REPLICATION_TIME_SETTING;
+import static org.opensearch.index.SegmentReplicationPressureService.SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED;
+import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertAcked;
+
+@OpenSearchIntegTestCase.ClusterScope(scope = OpenSearchIntegTestCase.Scope.TEST, numDataNodes = 0)
+public class SegmentReplicationPressureIT extends SegmentReplicationBaseIT {
+
+    private static final int MAX_CHECKPOINTS_BEHIND = 2;
+
+    @Override
+    protected Settings nodeSettings(int nodeOrdinal) {
+        return Settings.builder()
+            .put(super.nodeSettings(nodeOrdinal))
+            .put(SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED.getKey(), true)
+            .put(MAX_REPLICATION_TIME_SETTING.getKey(), TimeValue.timeValueSeconds(1))
+            .put(MAX_INDEXING_CHECKPOINTS.getKey(), MAX_CHECKPOINTS_BEHIND)
+            .build();
+    }
+
+    @Override
+    protected Collection<Class<? extends Plugin>> nodePlugins() {
+        return asList(MockTransportService.TestPlugin.class);
+    }
+
+    @AwaitsFix(bugUrl = "https://github.com/opensearch-project/OpenSearch/issues/6671")
+    public void testWritesRejected() throws Exception {
+        final String primaryNode = internalCluster().startNode();
+        createIndex(INDEX_NAME);
+        ensureYellowAndNoInitializingShards(INDEX_NAME);
+        final String replicaNode = internalCluster().startNode();
+        ensureGreen(INDEX_NAME);
+
+        final IndexShard primaryShard = getIndexShard(primaryNode, INDEX_NAME);
+        final List<String> replicaNodes = asList(replicaNode);
+        assertEqualSegmentInfosVersion(replicaNodes, primaryShard);
+
+        final CountDownLatch latch = new CountDownLatch(1);
+        final AtomicInteger totalDocs = new AtomicInteger(0);
+        try (final Releasable ignored = blockReplication(replicaNodes, latch)) {
+            Thread indexingThread = new Thread(() -> { totalDocs.getAndSet(indexUntilCheckpointCount()); });
+            indexingThread.start();
+            indexingThread.join();
+            latch.await();
+            // index again while we are stale.
+            assertBusy(() -> {
+                expectThrows(OpenSearchRejectedExecutionException.class, () -> {
+                    indexDoc();
+                    totalDocs.incrementAndGet();
+                });
+            });
+        }
+        refresh(INDEX_NAME);
+        // wait for the replicas to catch up after block is released.
+        waitForSearchableDocs(totalDocs.get(), replicaNodes.toArray(new String[] {}));
+
+        // index another doc showing there is no pressure enforced.
+        indexDoc();
+        waitForSearchableDocs(totalDocs.incrementAndGet(), replicaNodes.toArray(new String[] {}));
+        verifyStoreContent();
+    }
+
+    /**
+     * This test ensures that a replica can be added while the index is under write block.
+     * Ensuring that only write requests are blocked.
+     */
+    @AwaitsFix(bugUrl = "https://github.com/opensearch-project/OpenSearch/issues/6671")
+    public void testAddReplicaWhileWritesBlocked() throws Exception {
+        final String primaryNode = internalCluster().startNode();
+        createIndex(INDEX_NAME);
+        ensureYellowAndNoInitializingShards(INDEX_NAME);
+        final String replicaNode = internalCluster().startNode();
+        ensureGreen(INDEX_NAME);
+
+        final IndexShard primaryShard = getIndexShard(primaryNode, INDEX_NAME);
+        final List<String> replicaNodes = new ArrayList<>();
+        replicaNodes.add(replicaNode);
+        assertEqualSegmentInfosVersion(replicaNodes, primaryShard);
+
+        final CountDownLatch latch = new CountDownLatch(1);
+        final AtomicInteger totalDocs = new AtomicInteger(0);
+        try (final Releasable ignored = blockReplication(replicaNodes, latch)) {
+            Thread indexingThread = new Thread(() -> { totalDocs.getAndSet(indexUntilCheckpointCount()); });
+            indexingThread.start();
+            indexingThread.join();
+            latch.await();
+            // index again while we are stale.
+            assertBusy(() -> {
+                expectThrows(OpenSearchRejectedExecutionException.class, () -> {
+                    indexDoc();
+                    totalDocs.incrementAndGet();
+                });
+            });
+            final String replica_2 = internalCluster().startNode();
+            assertAcked(
+                client().admin()
+                    .indices()
+                    .prepareUpdateSettings(INDEX_NAME)
+                    .setSettings(Settings.builder().put(SETTING_NUMBER_OF_REPLICAS, 2))
+            );
+            ensureGreen(INDEX_NAME);
+            replicaNodes.add(replica_2);
+            waitForSearchableDocs(totalDocs.get(), replica_2);
+        }
+        refresh(INDEX_NAME);
+        // wait for the replicas to catch up after block is released.
+        waitForSearchableDocs(totalDocs.get(), replicaNodes.toArray(new String[] {}));
+
+        // index another doc showing there is no pressure enforced.
+        indexDoc();
+        waitForSearchableDocs(totalDocs.incrementAndGet(), replicaNodes.toArray(new String[] {}));
+        verifyStoreContent();
+    }
+
+    public void testBelowReplicaLimit() throws Exception {
+        final Settings settings = Settings.builder().put(indexSettings()).put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, 3).build();
+        final String primaryNode = internalCluster().startNode();
+        createIndex(INDEX_NAME, settings);
+        ensureYellowAndNoInitializingShards(INDEX_NAME);
+        List<String> replicaNodes = new ArrayList<>();
+        for (int i = 0; i < 3; i++) {
+            replicaNodes.add(internalCluster().startNode());
+        }
+        ensureGreen(INDEX_NAME);
+
+        final IndexShard primaryShard = getIndexShard(primaryNode, INDEX_NAME);
+        assertEqualSegmentInfosVersion(replicaNodes, primaryShard);
+
+        final CountDownLatch latch = new CountDownLatch(1);
+        final AtomicInteger totalDocs = new AtomicInteger(0);
+        // only block a single replica, pressure should not get applied.
+        try (final Releasable ignored = blockReplication(replicaNodes.subList(0, 1), latch)) {
+            Thread indexingThread = new Thread(() -> totalDocs.getAndSet(indexUntilCheckpointCount()));
+            indexingThread.start();
+            indexingThread.join();
+            latch.await();
+            indexDoc();
+            totalDocs.incrementAndGet();
+            refresh(INDEX_NAME);
+        }
+        // index another doc showing there is no pressure enforced.
+        indexDoc();
+        refresh(INDEX_NAME);
+        waitForSearchableDocs(totalDocs.incrementAndGet(), replicaNodes.toArray(new String[] {}));
+        verifyStoreContent();
+    }
+
+    public void testBulkWritesRejected() throws Exception {
+        final String primaryNode = internalCluster().startNode();
+        createIndex(INDEX_NAME);
+        ensureYellowAndNoInitializingShards(INDEX_NAME);
+        final String replicaNode = internalCluster().startNode();
+        final String coordinator = internalCluster().startCoordinatingOnlyNode(Settings.EMPTY);
+        ensureGreen(INDEX_NAME);
+
+        final IndexShard primaryShard = getIndexShard(primaryNode, INDEX_NAME);
+        final List<String> replicaNodes = asList(replicaNode);
+        assertEqualSegmentInfosVersion(replicaNodes, primaryShard);
+
+        final CountDownLatch latch = new CountDownLatch(1);
+        List<String> nodes = List.of(primaryNode, replicaNode, coordinator);
+
+        int docsPerBatch = randomIntBetween(1, 200);
+        int totalDocs = docsPerBatch * MAX_CHECKPOINTS_BEHIND;
+        try (final Releasable ignored = blockReplication(replicaNodes, latch)) {
+            Thread indexingThread = new Thread(() -> {
+                for (int i = 0; i < MAX_CHECKPOINTS_BEHIND + 1; i++) {
+                    executeBulkRequest(nodes, docsPerBatch);
+                    refresh(INDEX_NAME);
+                }
+            });
+            indexingThread.start();
+            indexingThread.join();
+            latch.await();
+            // try and index again while we are stale.
+            assertBusy(() -> { assertFailedRequests(executeBulkRequest(nodes, randomIntBetween(1, 200))); });
+        }
+        refresh(INDEX_NAME);
+        // wait for the replicas to catch up after block is released.
+        waitForSearchableDocs(totalDocs, replicaNodes.toArray(new String[] {}));
+
+        // index another doc showing there is no pressure enforced.
+        executeBulkRequest(nodes, totalDocs);
+        waitForSearchableDocs(totalDocs * 2L, replicaNodes.toArray(new String[] {}));
+        verifyStoreContent();
+    }
+
+    private BulkResponse executeBulkRequest(List<String> nodes, int docsPerBatch) {
+        final BulkRequest bulkRequest = new BulkRequest();
+        for (int j = 0; j < docsPerBatch; ++j) {
+            IndexRequest request = new IndexRequest(INDEX_NAME).id(UUIDs.base64UUID())
+                .source(Collections.singletonMap("key", randomAlphaOfLength(50)));
+            bulkRequest.add(request);
+        }
+        final BulkResponse bulkItemResponses = client(randomFrom(nodes)).bulk(bulkRequest).actionGet();
+        refresh(INDEX_NAME);
+        return bulkItemResponses;
+    }
+
+    /**
+     * Index and Refresh in batches to force checkpoints behind.
+     * Asserts that there are no stale replicas according to the primary until cp count is reached.
+     */
+    private int indexUntilCheckpointCount() {
+        int total = 0;
+        for (int i = 0; i < MAX_CHECKPOINTS_BEHIND; i++) {
+            final int numDocs = randomIntBetween(1, 100);
+            for (int j = 0; j < numDocs; ++j) {
+                indexDoc();
+            }
+            total += numDocs;
+            refresh(INDEX_NAME);
+        }
+        return total;
+    }
+
+    private void assertFailedRequests(BulkResponse response) {
+        assertTrue(Arrays.stream(response.getItems()).allMatch(BulkItemResponse::isFailed));
+        assertTrue(
+            Arrays.stream(response.getItems())
+                .map(BulkItemResponse::getFailure)
+                .allMatch((failure) -> failure.getStatus() == RestStatus.TOO_MANY_REQUESTS)
+        );
+    }
+
+    private void indexDoc() {
+        client().prepareIndex(INDEX_NAME).setId(UUIDs.base64UUID()).setSource("{}", "{}").get();
+    }
+
+    private void assertEqualSegmentInfosVersion(List<String> replicaNames, IndexShard primaryShard) {
+        for (String replicaName : replicaNames) {
+            final IndexShard replicaShard = getIndexShard(replicaName, INDEX_NAME);
+            assertEquals(
+                primaryShard.getLatestReplicationCheckpoint().getSegmentInfosVersion(),
+                replicaShard.getLatestReplicationCheckpoint().getSegmentInfosVersion()
+            );
+        }
+    }
+}
diff --git a/server/src/internalClusterTest/java/org/opensearch/indexing/IndexActionIT.java b/server/src/internalClusterTest/java/org/opensearch/indexing/IndexActionIT.java
index 45fbb2651a96d..73d6d9aff7b72 100644
--- a/server/src/internalClusterTest/java/org/opensearch/indexing/IndexActionIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/indexing/IndexActionIT.java
@@ -288,10 +288,9 @@ public void testInvalidIndexName() {
     }
 
     public void testDocumentWithBlankFieldName() {
-        MapperParsingException e = expectThrows(
-            MapperParsingException.class,
-            () -> { client().prepareIndex("test").setId("1").setSource("", "value1_2").execute().actionGet(); }
-        );
+        MapperParsingException e = expectThrows(MapperParsingException.class, () -> {
+            client().prepareIndex("test").setId("1").setSource("", "value1_2").execute().actionGet();
+        });
         assertThat(e.getMessage(), containsString("failed to parse"));
         assertThat(e.getRootCause().getMessage(), containsString("field name cannot be an empty string"));
     }
diff --git a/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationAllocationIT.java b/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationAllocationIT.java
new file mode 100644
index 0000000000000..c95c8e30342af
--- /dev/null
+++ b/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationAllocationIT.java
@@ -0,0 +1,267 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.indices.replication;
+
+import com.carrotsearch.hppc.cursors.ObjectObjectCursor;
+import org.opensearch.cluster.ClusterState;
+import org.opensearch.cluster.metadata.IndexMetadata;
+import org.opensearch.cluster.routing.IndexRoutingTable;
+import org.opensearch.cluster.routing.RoutingNode;
+import org.opensearch.cluster.routing.RoutingNodes;
+import org.opensearch.cluster.routing.ShardRouting;
+import org.opensearch.cluster.routing.allocation.allocator.BalancedShardsAllocator;
+import org.opensearch.common.settings.Settings;
+import org.opensearch.common.unit.TimeValue;
+import org.opensearch.index.IndexModule;
+import org.opensearch.indices.replication.common.ReplicationType;
+import org.opensearch.test.InternalTestCluster;
+import org.opensearch.test.OpenSearchIntegTestCase;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
+
+import static org.opensearch.cluster.routing.ShardRoutingState.STARTED;
+import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertAcked;
+
+import org.opensearch.cluster.OpenSearchAllocationTestCase.ShardAllocations;
+
+@OpenSearchIntegTestCase.ClusterScope(scope = OpenSearchIntegTestCase.Scope.TEST, numDataNodes = 0)
+public class SegmentReplicationAllocationIT extends SegmentReplicationBaseIT {
+
+    private void createIndex(String idxName, int shardCount, int replicaCount, boolean isSegRep) {
+        Settings.Builder builder = Settings.builder()
+            .put(IndexMetadata.SETTING_NUMBER_OF_SHARDS, shardCount)
+            .put(IndexModule.INDEX_QUERY_CACHE_ENABLED_SETTING.getKey(), false)
+            .put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, replicaCount);
+        if (isSegRep) {
+            builder = builder.put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT);
+        } else {
+            builder = builder.put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.DOCUMENT);
+        }
+        prepareCreate(idxName, builder).get();
+    }
+
+    public void enablePreferPrimaryBalance() {
+        assertAcked(
+            client().admin()
+                .cluster()
+                .prepareUpdateSettings()
+                .setPersistentSettings(Settings.builder().put(BalancedShardsAllocator.PREFER_PRIMARY_SHARD_BALANCE.getKey(), "true"))
+        );
+    }
+
+    /**
+     * This test verifies that the overall primary balance is attained during allocation. This test verifies primary
+     * balance per index and across all indices is maintained.
+     * @throws Exception
+     */
+    public void testGlobalPrimaryAllocation() throws Exception {
+        internalCluster().startClusterManagerOnlyNode();
+        final int maxReplicaCount = 1;
+        final int maxShardCount = 1;
+        final int nodeCount = randomIntBetween(maxReplicaCount + 1, 10);
+        final int numberOfIndices = randomIntBetween(5, 10);
+
+        final List<String> nodeNames = new ArrayList<>();
+        logger.info("--> Creating {} nodes", nodeCount);
+        for (int i = 0; i < nodeCount; i++) {
+            nodeNames.add(internalCluster().startNode());
+        }
+        enablePreferPrimaryBalance();
+        int shardCount, replicaCount;
+        ClusterState state;
+        for (int i = 0; i < numberOfIndices; i++) {
+            shardCount = randomIntBetween(1, maxShardCount);
+            replicaCount = randomIntBetween(0, maxReplicaCount);
+            createIndex("test" + i, shardCount, replicaCount, i % 2 == 0);
+            logger.info("--> Creating index {} with shard count {} and replica count {}", "test" + i, shardCount, replicaCount);
+            ensureGreen(TimeValue.timeValueSeconds(60));
+        }
+        state = client().admin().cluster().prepareState().execute().actionGet().getState();
+        logger.info(ShardAllocations.printShardDistribution(state));
+        verifyPerIndexPrimaryBalance();
+        verifyPrimaryBalance();
+    }
+
+    /**
+     * This test verifies the happy path where primary shard allocation is balanced when multiple indices are created.
+     *
+     * This test in general passes without primary shard balance as well due to nature of allocation algorithm which
+     * assigns all primary shards first followed by replica copies.
+     */
+    public void testPerIndexPrimaryAllocation() throws Exception {
+        internalCluster().startClusterManagerOnlyNode();
+        final int maxReplicaCount = 2;
+        final int maxShardCount = 5;
+        final int nodeCount = randomIntBetween(maxReplicaCount + 1, 10);
+        final int numberOfIndices = randomIntBetween(5, 10);
+
+        final List<String> nodeNames = new ArrayList<>();
+        logger.info("--> Creating {} nodes", nodeCount);
+        for (int i = 0; i < nodeCount; i++) {
+            nodeNames.add(internalCluster().startNode());
+        }
+        enablePreferPrimaryBalance();
+        int shardCount, replicaCount;
+        ClusterState state;
+        for (int i = 0; i < numberOfIndices; i++) {
+            shardCount = randomIntBetween(1, maxShardCount);
+            replicaCount = randomIntBetween(0, maxReplicaCount);
+            createIndex("test" + i, shardCount, replicaCount, i % 2 == 0);
+            logger.info("--> Creating index {} with shard count {} and replica count {}", "test" + i, shardCount, replicaCount);
+            ensureGreen(TimeValue.timeValueSeconds(60));
+            state = client().admin().cluster().prepareState().execute().actionGet().getState();
+            logger.info(ShardAllocations.printShardDistribution(state));
+        }
+        verifyPerIndexPrimaryBalance();
+    }
+
+    /**
+     * This test verifies balanced primary shard allocation for a single index with large shard count in event of node
+     * going down and a new node joining the cluster. The results in shard distribution skewness and re-balancing logic
+     * ensures the primary shard distribution is balanced.
+     *
+     */
+    public void testSingleIndexShardAllocation() throws Exception {
+        internalCluster().startClusterManagerOnlyNode();
+        final int maxReplicaCount = 1;
+        final int maxShardCount = 50;
+        final int nodeCount = 5;
+
+        final List<String> nodeNames = new ArrayList<>();
+        logger.info("--> Creating {} nodes", nodeCount);
+        for (int i = 0; i < nodeCount; i++) {
+            nodeNames.add(internalCluster().startNode());
+        }
+        enablePreferPrimaryBalance();
+
+        ClusterState state;
+        createIndex("test", maxShardCount, maxReplicaCount, true);
+        ensureGreen(TimeValue.timeValueSeconds(60));
+        state = client().admin().cluster().prepareState().execute().actionGet().getState();
+        logger.info(ShardAllocations.printShardDistribution(state));
+        verifyPerIndexPrimaryBalance();
+
+        // Remove a node
+        internalCluster().stopRandomNode(InternalTestCluster.nameFilter(nodeNames.get(0)));
+        ensureGreen(TimeValue.timeValueSeconds(60));
+        state = client().admin().cluster().prepareState().execute().actionGet().getState();
+        logger.info(ShardAllocations.printShardDistribution(state));
+        verifyPerIndexPrimaryBalance();
+
+        // Add a new node
+        internalCluster().startDataOnlyNode();
+        ensureGreen(TimeValue.timeValueSeconds(60));
+        state = client().admin().cluster().prepareState().execute().actionGet().getState();
+        logger.info(ShardAllocations.printShardDistribution(state));
+        verifyPerIndexPrimaryBalance();
+    }
+
+    /**
+     * Similar to testSingleIndexShardAllocation test but creates multiple indices, multiple node adding in and getting
+     * removed. The test asserts post each such event that primary shard distribution is balanced across single index.
+     */
+    public void testAllocationWithDisruption() throws Exception {
+        internalCluster().startClusterManagerOnlyNode();
+        final int maxReplicaCount = 2;
+        final int maxShardCount = 5;
+        final int nodeCount = randomIntBetween(maxReplicaCount + 1, 10);
+        final int numberOfIndices = randomIntBetween(1, 10);
+
+        logger.info("--> Creating {} nodes", nodeCount);
+        final List<String> nodeNames = new ArrayList<>();
+        for (int i = 0; i < nodeCount; i++) {
+            nodeNames.add(internalCluster().startNode());
+        }
+        enablePreferPrimaryBalance();
+
+        int shardCount, replicaCount, totalShardCount = 0, totalReplicaCount = 0;
+        ClusterState state;
+        for (int i = 0; i < numberOfIndices; i++) {
+            shardCount = randomIntBetween(1, maxShardCount);
+            totalShardCount += shardCount;
+            replicaCount = randomIntBetween(1, maxReplicaCount);
+            totalReplicaCount += replicaCount;
+            logger.info("--> Creating index test{} with primary {} and replica {}", i, shardCount, replicaCount);
+            createIndex("test" + i, shardCount, replicaCount, i % 2 == 0);
+            ensureGreen(TimeValue.timeValueSeconds(60));
+            if (logger.isTraceEnabled()) {
+                state = client().admin().cluster().prepareState().execute().actionGet().getState();
+                logger.info(ShardAllocations.printShardDistribution(state));
+            }
+        }
+        state = client().admin().cluster().prepareState().execute().actionGet().getState();
+        logger.info(ShardAllocations.printShardDistribution(state));
+        verifyPerIndexPrimaryBalance();
+
+        final int additionalNodeCount = randomIntBetween(1, 5);
+        logger.info("--> Adding {} nodes", additionalNodeCount);
+
+        internalCluster().startNodes(additionalNodeCount);
+        ensureGreen(TimeValue.timeValueSeconds(60));
+        state = client().admin().cluster().prepareState().execute().actionGet().getState();
+        logger.info(ShardAllocations.printShardDistribution(state));
+        verifyPerIndexPrimaryBalance();
+
+        logger.info("--> Stop one third nodes");
+        for (int i = 0; i < nodeCount; i += 3) {
+            internalCluster().stopRandomNode(InternalTestCluster.nameFilter(nodeNames.get(i)));
+            // give replica a chance to promote as primary before terminating node containing the replica
+            ensureGreen(TimeValue.timeValueSeconds(60));
+        }
+        state = client().admin().cluster().prepareState().execute().actionGet().getState();
+        logger.info(ShardAllocations.printShardDistribution(state));
+        verifyPerIndexPrimaryBalance();
+    }
+
+    /**
+     * Utility method which ensures cluster has balanced primary shard distribution across a single index.
+     * @throws Exception exception
+     */
+    private void verifyPerIndexPrimaryBalance() throws Exception {
+        assertBusy(() -> {
+            final ClusterState currentState = client().admin().cluster().prepareState().execute().actionGet().getState();
+            RoutingNodes nodes = currentState.getRoutingNodes();
+            for (ObjectObjectCursor<String, IndexRoutingTable> index : currentState.getRoutingTable().indicesRouting()) {
+                final int totalPrimaryShards = index.value.primaryShardsActive();
+                final int avgPrimaryShardsPerNode = (int) Math.ceil(totalPrimaryShards * 1f / currentState.getRoutingNodes().size());
+                for (RoutingNode node : nodes) {
+                    final int primaryCount = node.shardsWithState(index.key, STARTED)
+                        .stream()
+                        .filter(ShardRouting::primary)
+                        .collect(Collectors.toList())
+                        .size();
+                    assertTrue(primaryCount <= avgPrimaryShardsPerNode);
+                }
+            }
+        }, 60, TimeUnit.SECONDS);
+    }
+
+    private void verifyPrimaryBalance() throws Exception {
+        assertBusy(() -> {
+            final ClusterState currentState = client().admin().cluster().prepareState().execute().actionGet().getState();
+            RoutingNodes nodes = currentState.getRoutingNodes();
+            int totalPrimaryShards = 0;
+            for (ObjectObjectCursor<String, IndexRoutingTable> index : currentState.getRoutingTable().indicesRouting()) {
+                totalPrimaryShards += index.value.primaryShardsActive();
+            }
+            final int avgPrimaryShardsPerNode = (int) Math.ceil(totalPrimaryShards * 1f / currentState.getRoutingNodes().size());
+            for (RoutingNode node : nodes) {
+                final int primaryCount = node.shardsWithState(STARTED)
+                    .stream()
+                    .filter(ShardRouting::primary)
+                    .collect(Collectors.toList())
+                    .size();
+                assertTrue(primaryCount <= avgPrimaryShardsPerNode);
+            }
+        }, 60, TimeUnit.SECONDS);
+    }
+}
diff --git a/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationBaseIT.java b/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationBaseIT.java
index dfffeaf860734..e9626e6ecc0bd 100644
--- a/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationBaseIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationBaseIT.java
@@ -8,6 +8,7 @@
 
 package org.opensearch.indices.replication;
 
+import org.opensearch.action.admin.indices.replication.SegmentReplicationStatsResponse;
 import org.opensearch.action.search.SearchResponse;
 import org.opensearch.cluster.ClusterState;
 import org.opensearch.cluster.metadata.IndexMetadata;
@@ -16,11 +17,13 @@
 import org.opensearch.cluster.routing.IndexShardRoutingTable;
 import org.opensearch.cluster.routing.ShardRouting;
 import org.opensearch.common.Nullable;
+import org.opensearch.common.lease.Releasable;
 import org.opensearch.common.settings.Settings;
 import org.opensearch.common.util.FeatureFlags;
 import org.opensearch.index.Index;
 import org.opensearch.index.IndexModule;
 import org.opensearch.index.IndexService;
+import org.opensearch.index.SegmentReplicationPerGroupStats;
 import org.opensearch.index.shard.IndexShard;
 import org.opensearch.index.store.Store;
 import org.opensearch.index.store.StoreFileMetadata;
@@ -29,12 +32,14 @@
 import org.opensearch.plugins.Plugin;
 import org.opensearch.test.OpenSearchIntegTestCase;
 import org.opensearch.test.transport.MockTransportService;
+import org.opensearch.transport.TransportService;
 
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
+import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
 
@@ -134,6 +139,24 @@ protected void waitForSearchableDocs(long docCount, String... nodes) throws Exce
         waitForSearchableDocs(docCount, Arrays.stream(nodes).collect(Collectors.toList()));
     }
 
+    protected void waitForSegmentReplication(String node) throws Exception {
+        assertBusy(() -> {
+            SegmentReplicationStatsResponse segmentReplicationStatsResponse = client(node).admin()
+                .indices()
+                .prepareSegmentReplicationStats(INDEX_NAME)
+                .setDetailed(true)
+                .execute()
+                .actionGet();
+            final SegmentReplicationPerGroupStats perGroupStats = segmentReplicationStatsResponse.getReplicationStats()
+                .get(INDEX_NAME)
+                .get(0);
+            assertEquals(
+                perGroupStats.getReplicaStats().stream().findFirst().get().getCurrentReplicationState().getStage(),
+                SegmentReplicationState.Stage.DONE
+            );
+        }, 1, TimeUnit.MINUTES);
+    }
+
     protected void verifyStoreContent() throws Exception {
         assertBusy(() -> {
             final ClusterState clusterState = getClusterState();
@@ -182,4 +205,31 @@ protected IndexShard getIndexShard(String node, String indexName) {
         return indexService.getShard(shardId.get());
     }
 
+    protected Releasable blockReplication(List<String> nodes, CountDownLatch latch) {
+        CountDownLatch pauseReplicationLatch = new CountDownLatch(nodes.size());
+        for (String node : nodes) {
+
+            MockTransportService mockTargetTransportService = ((MockTransportService) internalCluster().getInstance(
+                TransportService.class,
+                node
+            ));
+            mockTargetTransportService.addSendBehavior((connection, requestId, action, request, options) -> {
+                if (action.equals(SegmentReplicationSourceService.Actions.GET_SEGMENT_FILES)) {
+                    try {
+                        latch.countDown();
+                        pauseReplicationLatch.await();
+                    } catch (InterruptedException e) {
+                        throw new RuntimeException(e);
+                    }
+                }
+                connection.sendRequest(requestId, action, request, options);
+            });
+        }
+        return () -> {
+            while (pauseReplicationLatch.getCount() > 0) {
+                pauseReplicationLatch.countDown();
+            }
+        };
+    }
+
 }
diff --git a/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationIT.java b/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationIT.java
index 9975a5ff65a34..51c0c8710d39d 100644
--- a/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationIT.java
@@ -9,31 +9,52 @@
 package org.opensearch.indices.replication;
 
 import com.carrotsearch.randomizedtesting.RandomizedTest;
+import org.apache.lucene.document.Document;
+import org.apache.lucene.document.Field;
+import org.apache.lucene.document.SortedDocValuesField;
+import org.apache.lucene.document.StringField;
+import org.apache.lucene.document.TextField;
+import org.apache.lucene.index.IndexWriter;
+import org.apache.lucene.index.IndexWriterConfig;
+import org.apache.lucene.index.SegmentInfos;
+import org.apache.lucene.tests.util.TestUtil;
+import org.apache.lucene.util.BytesRef;
 import org.opensearch.action.support.WriteRequest;
 import org.opensearch.action.update.UpdateResponse;
 import org.opensearch.client.Requests;
+import org.opensearch.cluster.health.ClusterHealthStatus;
+import org.opensearch.cluster.ClusterState;
 import org.opensearch.cluster.metadata.IndexMetadata;
+import org.opensearch.cluster.node.DiscoveryNode;
 import org.opensearch.cluster.routing.ShardRouting;
+import org.opensearch.cluster.routing.ShardRoutingState;
 import org.opensearch.cluster.routing.allocation.command.CancelAllocationCommand;
 import org.opensearch.common.settings.Settings;
 import org.opensearch.index.IndexModule;
+import org.opensearch.index.SegmentReplicationPerGroupStats;
+import org.opensearch.index.SegmentReplicationPressureService;
+import org.opensearch.index.SegmentReplicationShardStats;
 import org.opensearch.index.shard.IndexShard;
+import org.opensearch.index.shard.ShardId;
 import org.opensearch.indices.recovery.FileChunkRequest;
 import org.opensearch.indices.replication.common.ReplicationType;
+import org.opensearch.node.NodeClosedException;
 import org.opensearch.test.BackgroundIndexer;
 import org.opensearch.test.InternalTestCluster;
 import org.opensearch.test.OpenSearchIntegTestCase;
 import org.opensearch.test.transport.MockTransportService;
 import org.opensearch.transport.TransportService;
 
+import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.CountDownLatch;
 
 import static java.util.Arrays.asList;
 import static org.opensearch.index.query.QueryBuilders.matchQuery;
-import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertHitCount;
 import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertAcked;
+import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertHitCount;
 import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertSearchHits;
 
 @OpenSearchIntegTestCase.ClusterScope(scope = OpenSearchIntegTestCase.Scope.TEST, numDataNodes = 0)
@@ -284,6 +305,105 @@ public void testReplicationAfterForceMerge() throws Exception {
         }
     }
 
+    /**
+     * This test verifies that segment replication does not fail for closed indices
+     */
+    public void testClosedIndices() {
+        internalCluster().startClusterManagerOnlyNode();
+        List<String> nodes = new ArrayList<>();
+        // start 1st node so that it contains the primary
+        nodes.add(internalCluster().startNode());
+        createIndex(INDEX_NAME, super.indexSettings());
+        ensureYellowAndNoInitializingShards(INDEX_NAME);
+        // start 2nd node so that it contains the replica
+        nodes.add(internalCluster().startNode());
+        ensureGreen(INDEX_NAME);
+
+        logger.info("--> Close index");
+        assertAcked(client().admin().indices().prepareClose(INDEX_NAME));
+
+        logger.info("--> waiting for allocation to have shards assigned");
+        waitForRelocation(ClusterHealthStatus.GREEN);
+    }
+
+    /**
+     * This test validates the primary node drop does not result in shard failure on replica.
+     * @throws Exception
+     */
+    public void testNodeDropWithOngoingReplication() throws Exception {
+        internalCluster().startClusterManagerOnlyNode();
+        final String primaryNode = internalCluster().startNode();
+        createIndex(
+            INDEX_NAME,
+            Settings.builder()
+                .put(indexSettings())
+                .put(IndexMetadata.SETTING_NUMBER_OF_SHARDS, 1)
+                .put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, 1)
+                .put("index.refresh_interval", -1)
+                .build()
+        );
+        ensureYellow(INDEX_NAME);
+        final String replicaNode = internalCluster().startNode();
+        ensureGreen(INDEX_NAME);
+        ClusterState state = client().admin().cluster().prepareState().execute().actionGet().getState();
+        // Get replica allocation id
+        final String replicaAllocationId = state.routingTable()
+            .index(INDEX_NAME)
+            .shardsWithState(ShardRoutingState.STARTED)
+            .stream()
+            .filter(routing -> routing.primary() == false)
+            .findFirst()
+            .get()
+            .allocationId()
+            .getId();
+        DiscoveryNode primaryDiscovery = state.nodes().resolveNode(primaryNode);
+
+        CountDownLatch blockFileCopy = new CountDownLatch(1);
+        MockTransportService primaryTransportService = ((MockTransportService) internalCluster().getInstance(
+            TransportService.class,
+            primaryNode
+        ));
+        primaryTransportService.addSendBehavior(
+            internalCluster().getInstance(TransportService.class, replicaNode),
+            (connection, requestId, action, request, options) -> {
+                if (action.equals(SegmentReplicationTargetService.Actions.FILE_CHUNK)) {
+                    FileChunkRequest req = (FileChunkRequest) request;
+                    logger.debug("file chunk [{}] lastChunk: {}", req, req.lastChunk());
+                    if (req.name().endsWith("cfs") && req.lastChunk()) {
+                        try {
+                            blockFileCopy.await();
+                        } catch (InterruptedException e) {
+                            throw new RuntimeException(e);
+                        }
+                        throw new NodeClosedException(primaryDiscovery);
+                    }
+                }
+                connection.sendRequest(requestId, action, request, options);
+            }
+        );
+        final int docCount = scaledRandomIntBetween(10, 200);
+        for (int i = 0; i < docCount; i++) {
+            client().prepareIndex(INDEX_NAME).setId(Integer.toString(i)).setSource("field", "value" + i).execute().get();
+        }
+        // Refresh, this should trigger round of segment replication
+        refresh(INDEX_NAME);
+        blockFileCopy.countDown();
+        internalCluster().stopRandomNode(InternalTestCluster.nameFilter(primaryNode));
+        assertBusy(() -> { assertDocCounts(docCount, replicaNode); });
+        state = client().admin().cluster().prepareState().execute().actionGet().getState();
+        // replica now promoted as primary should have same allocation id
+        final String currentAllocationID = state.routingTable()
+            .index(INDEX_NAME)
+            .shardsWithState(ShardRoutingState.STARTED)
+            .stream()
+            .filter(routing -> routing.primary())
+            .findFirst()
+            .get()
+            .allocationId()
+            .getId();
+        assertEquals(currentAllocationID, replicaAllocationId);
+    }
+
     public void testCancellation() throws Exception {
         final String primaryNode = internalCluster().startNode();
         createIndex(INDEX_NAME, Settings.builder().put(indexSettings()).put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, 1).build());
@@ -423,6 +543,68 @@ public void testDeleteOperations() throws Exception {
         }
     }
 
+    /**
+     * This tests that the max seqNo we send to replicas is accurate and that after failover
+     * the new primary starts indexing from the correct maxSeqNo and replays the correct count of docs
+     * from xlog.
+     */
+    public void testReplicationPostDeleteAndForceMerge() throws Exception {
+        final String primary = internalCluster().startNode();
+        createIndex(INDEX_NAME);
+        final String replica = internalCluster().startNode();
+        ensureGreen(INDEX_NAME);
+        final int initialDocCount = scaledRandomIntBetween(10, 200);
+        for (int i = 0; i < initialDocCount; i++) {
+            client().prepareIndex(INDEX_NAME).setId(String.valueOf(i)).setSource("foo", "bar").get();
+        }
+        refresh(INDEX_NAME);
+        waitForSearchableDocs(initialDocCount, primary, replica);
+
+        final int deletedDocCount = randomIntBetween(10, initialDocCount);
+        for (int i = 0; i < deletedDocCount; i++) {
+            client(primary).prepareDelete(INDEX_NAME, String.valueOf(i)).setRefreshPolicy(WriteRequest.RefreshPolicy.IMMEDIATE).get();
+        }
+        client().admin().indices().prepareForceMerge(INDEX_NAME).setMaxNumSegments(1).setFlush(false).get();
+
+        // randomly flush here after the force merge to wipe any old segments.
+        if (randomBoolean()) {
+            flush(INDEX_NAME);
+        }
+
+        final IndexShard primaryShard = getIndexShard(primary, INDEX_NAME);
+        final IndexShard replicaShard = getIndexShard(replica, INDEX_NAME);
+        assertBusy(
+            () -> assertEquals(
+                primaryShard.getLatestReplicationCheckpoint().getSegmentInfosVersion(),
+                replicaShard.getLatestReplicationCheckpoint().getSegmentInfosVersion()
+            )
+        );
+
+        // add some docs to the xlog and drop primary.
+        final int additionalDocs = randomIntBetween(1, 50);
+        for (int i = initialDocCount; i < initialDocCount + additionalDocs; i++) {
+            client().prepareIndex(INDEX_NAME).setId(String.valueOf(i)).setSource("foo", "bar").get();
+        }
+        // Drop the primary and wait until replica is promoted.
+        internalCluster().stopRandomNode(InternalTestCluster.nameFilter(primary));
+        ensureYellowAndNoInitializingShards(INDEX_NAME);
+
+        final ShardRouting replicaShardRouting = getShardRoutingForNodeName(replica);
+        assertNotNull(replicaShardRouting);
+        assertTrue(replicaShardRouting + " should be promoted as a primary", replicaShardRouting.primary());
+        refresh(INDEX_NAME);
+        final long expectedHitCount = initialDocCount + additionalDocs - deletedDocCount;
+        assertHitCount(client(replica).prepareSearch(INDEX_NAME).setSize(0).setPreference("_only_local").get(), expectedHitCount);
+
+        int expectedMaxSeqNo = initialDocCount + deletedDocCount + additionalDocs - 1;
+        assertEquals(expectedMaxSeqNo, replicaShard.seqNoStats().getMaxSeqNo());
+
+        // index another doc.
+        client().prepareIndex(INDEX_NAME).setId(String.valueOf(expectedMaxSeqNo + 1)).setSource("another", "doc").get();
+        refresh(INDEX_NAME);
+        assertHitCount(client(replica).prepareSearch(INDEX_NAME).setSize(0).setPreference("_only_local").get(), expectedHitCount + 1);
+    }
+
     public void testUpdateOperations() throws Exception {
         internalCluster().startClusterManagerOnlyNode();
         final String primary = internalCluster().startDataOnlyNode();
@@ -516,4 +698,140 @@ public void testDropPrimaryDuringReplication() throws Exception {
             verifyStoreContent();
         }
     }
+
+    public void testReplicaHasDiffFilesThanPrimary() throws Exception {
+        internalCluster().startClusterManagerOnlyNode();
+        final String primaryNode = internalCluster().startNode();
+        createIndex(INDEX_NAME, Settings.builder().put(indexSettings()).put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, 1).build());
+        ensureYellow(INDEX_NAME);
+        final String replicaNode = internalCluster().startNode();
+        ensureGreen(INDEX_NAME);
+
+        final IndexShard replicaShard = getIndexShard(replicaNode, INDEX_NAME);
+        IndexWriterConfig iwc = newIndexWriterConfig().setOpenMode(IndexWriterConfig.OpenMode.APPEND);
+
+        // create a doc to index
+        int numDocs = 2 + random().nextInt(100);
+
+        List<Document> docs = new ArrayList<>();
+        for (int i = 0; i < numDocs; i++) {
+            Document doc = new Document();
+            doc.add(new StringField("id", "" + i, random().nextBoolean() ? Field.Store.YES : Field.Store.NO));
+            doc.add(
+                new TextField(
+                    "body",
+                    TestUtil.randomRealisticUnicodeString(random()),
+                    random().nextBoolean() ? Field.Store.YES : Field.Store.NO
+                )
+            );
+            doc.add(new SortedDocValuesField("dv", new BytesRef(TestUtil.randomRealisticUnicodeString(random()))));
+            docs.add(doc);
+        }
+        // create some segments on the replica before copy.
+        try (IndexWriter writer = new IndexWriter(replicaShard.store().directory(), iwc)) {
+            for (Document d : docs) {
+                writer.addDocument(d);
+            }
+            writer.flush();
+            writer.commit();
+        }
+
+        final SegmentInfos segmentInfos = SegmentInfos.readLatestCommit(replicaShard.store().directory());
+        replicaShard.finalizeReplication(segmentInfos);
+
+        final int docCount = scaledRandomIntBetween(10, 200);
+        for (int i = 0; i < docCount; i++) {
+            client().prepareIndex(INDEX_NAME).setId(Integer.toString(i)).setSource("field", "value" + i).execute().get();
+            refresh(INDEX_NAME);
+        }
+        // Refresh, this should trigger round of segment replication
+        assertBusy(() -> { assertDocCounts(docCount, replicaNode); });
+        final IndexShard replicaAfterFailure = getIndexShard(replicaNode, INDEX_NAME);
+        assertNotEquals(replicaAfterFailure.routingEntry().allocationId().getId(), replicaShard.routingEntry().allocationId().getId());
+    }
+
+    public void testPressureServiceStats() throws Exception {
+        final String primaryNode = internalCluster().startNode();
+        createIndex(INDEX_NAME);
+        final String replicaNode = internalCluster().startNode();
+        ensureGreen(INDEX_NAME);
+
+        int initialDocCount = scaledRandomIntBetween(100, 200);
+        try (
+            BackgroundIndexer indexer = new BackgroundIndexer(
+                INDEX_NAME,
+                "_doc",
+                client(),
+                -1,
+                RandomizedTest.scaledRandomIntBetween(2, 5),
+                false,
+                random()
+            )
+        ) {
+            indexer.start(initialDocCount);
+            waitForDocs(initialDocCount, indexer);
+            refresh(INDEX_NAME);
+
+            SegmentReplicationPressureService pressureService = internalCluster().getInstance(
+                SegmentReplicationPressureService.class,
+                primaryNode
+            );
+
+            final Map<ShardId, SegmentReplicationPerGroupStats> shardStats = pressureService.nodeStats().getShardStats();
+            assertEquals(1, shardStats.size());
+            final IndexShard primaryShard = getIndexShard(primaryNode, INDEX_NAME);
+            IndexShard replica = getIndexShard(replicaNode, INDEX_NAME);
+            SegmentReplicationPerGroupStats groupStats = shardStats.get(primaryShard.shardId());
+            Set<SegmentReplicationShardStats> replicaStats = groupStats.getReplicaStats();
+            assertEquals(1, replicaStats.size());
+
+            // assert replica node returns nothing.
+            SegmentReplicationPressureService replicaNode_service = internalCluster().getInstance(
+                SegmentReplicationPressureService.class,
+                replicaNode
+            );
+            assertTrue(replicaNode_service.nodeStats().getShardStats().isEmpty());
+
+            // drop the primary, this won't hand off SR state.
+            internalCluster().stopRandomNode(InternalTestCluster.nameFilter(primaryNode));
+            ensureYellowAndNoInitializingShards(INDEX_NAME);
+            replicaNode_service = internalCluster().getInstance(SegmentReplicationPressureService.class, replicaNode);
+            replica = getIndexShard(replicaNode, INDEX_NAME);
+            assertTrue("replica should be promoted as a primary", replica.routingEntry().primary());
+            assertEquals(1, replicaNode_service.nodeStats().getShardStats().size());
+            // we don't have a replica assigned yet, so this should be 0.
+            assertEquals(0, replicaNode_service.nodeStats().getShardStats().get(primaryShard.shardId()).getReplicaStats().size());
+
+            // start another replica.
+            String replicaNode_2 = internalCluster().startNode();
+            ensureGreen(INDEX_NAME);
+            String docId = String.valueOf(initialDocCount + 1);
+            client().prepareIndex(INDEX_NAME).setId(docId).setSource("foo", "bar").get();
+            refresh(INDEX_NAME);
+            waitForSearchableDocs(initialDocCount + 1, replicaNode_2);
+
+            replicaNode_service = internalCluster().getInstance(SegmentReplicationPressureService.class, replicaNode);
+            replica = getIndexShard(replicaNode_2, INDEX_NAME);
+            assertEquals(1, replicaNode_service.nodeStats().getShardStats().size());
+            replicaStats = replicaNode_service.nodeStats().getShardStats().get(primaryShard.shardId()).getReplicaStats();
+            assertEquals(1, replicaStats.size());
+
+            // test a checkpoint without any new segments
+            flush(INDEX_NAME);
+            assertBusy(() -> {
+                final SegmentReplicationPressureService service = internalCluster().getInstance(
+                    SegmentReplicationPressureService.class,
+                    replicaNode
+                );
+                assertEquals(1, service.nodeStats().getShardStats().size());
+                final Set<SegmentReplicationShardStats> shardStatsSet = service.nodeStats()
+                    .getShardStats()
+                    .get(primaryShard.shardId())
+                    .getReplicaStats();
+                assertEquals(1, shardStatsSet.size());
+                final SegmentReplicationShardStats stats = shardStatsSet.stream().findFirst().get();
+                assertEquals(0, stats.getCheckpointsBehindCount());
+            });
+        }
+    }
 }
diff --git a/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationRelocationIT.java b/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationRelocationIT.java
index a47b737c3e198..58e0686385d5e 100644
--- a/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationRelocationIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationRelocationIT.java
@@ -12,6 +12,7 @@
 import org.opensearch.action.ActionFuture;
 import org.opensearch.action.admin.cluster.health.ClusterHealthResponse;
 import org.opensearch.action.admin.cluster.reroute.ClusterRerouteResponse;
+import org.opensearch.action.admin.indices.replication.SegmentReplicationStatsResponse;
 import org.opensearch.action.index.IndexResponse;
 import org.opensearch.action.support.WriteRequest;
 import org.opensearch.cluster.ClusterState;
@@ -33,6 +34,7 @@
 
 import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_NUMBER_OF_REPLICAS;
 import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertAcked;
+import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertHitCount;
 
 /**
  * This test class verifies primary shard relocation with segment replication as replication strategy.
@@ -494,4 +496,67 @@ public void testAddNewReplicaFailure() throws Exception {
         assertTrue(clusterHealthResponse.isTimedOut());
         ensureYellow(INDEX_NAME);
     }
+
+    public void testFlushAfterRelocation() throws Exception {
+        // Starting two nodes with primary and replica shards respectively.
+        final String primaryNode = internalCluster().startNode();
+        prepareCreate(
+            INDEX_NAME,
+            Settings.builder()
+                // we want to control refreshes
+                .put("index.refresh_interval", -1)
+        ).get();
+        ensureYellowAndNoInitializingShards(INDEX_NAME);
+        final String replicaNode = internalCluster().startNode();
+        ensureGreen(INDEX_NAME);
+
+        // Start another empty node for relocation
+        final String newPrimary = internalCluster().startNode();
+        ClusterHealthResponse clusterHealthResponse = client().admin()
+            .cluster()
+            .prepareHealth()
+            .setWaitForEvents(Priority.LANGUID)
+            .setWaitForNodes("3")
+            .execute()
+            .actionGet();
+        assertEquals(clusterHealthResponse.isTimedOut(), false);
+        ensureGreen(INDEX_NAME);
+
+        // Start indexing docs
+        final int initialDocCount = scaledRandomIntBetween(2000, 3000);
+        for (int i = 0; i < initialDocCount; i++) {
+            client().prepareIndex(INDEX_NAME).setId(Integer.toString(i)).setSource("field", "value" + i).execute().actionGet();
+        }
+
+        // Verify segment replication event never happened on replica shard
+        SegmentReplicationStatsResponse segmentReplicationStatsResponse = dataNodeClient().admin()
+            .indices()
+            .prepareSegmentReplicationStats(INDEX_NAME)
+            .execute()
+            .actionGet();
+        assertTrue(segmentReplicationStatsResponse.getReplicationStats().get(INDEX_NAME).get(0).getReplicaStats().isEmpty());
+
+        // Relocate primary to new primary. When new primary starts it does perform a flush.
+        logger.info("--> relocate the shard from primary to newPrimary");
+        ActionFuture<ClusterRerouteResponse> relocationListener = client().admin()
+            .cluster()
+            .prepareReroute()
+            .add(new MoveAllocationCommand(INDEX_NAME, 0, primaryNode, newPrimary))
+            .execute();
+        clusterHealthResponse = client().admin()
+            .cluster()
+            .prepareHealth()
+            .setWaitForEvents(Priority.LANGUID)
+            .setWaitForNoRelocatingShards(true)
+            .setTimeout(ACCEPTABLE_RELOCATION_TIME)
+            .execute()
+            .actionGet();
+        assertEquals(clusterHealthResponse.isTimedOut(), false);
+
+        // Verify if all docs are present in replica after relocation, if new relocated primary doesn't flush after relocation the below
+        // assert will fail.
+        assertBusy(() -> {
+            assertHitCount(client(replicaNode).prepareSearch(INDEX_NAME).setPreference("_only_local").setSize(0).get(), initialDocCount);
+        });
+    }
 }
diff --git a/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationStatsIT.java b/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationStatsIT.java
index 6969f28a784d9..d162e51616831 100644
--- a/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationStatsIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationStatsIT.java
@@ -8,15 +8,21 @@
 
 package org.opensearch.indices.replication;
 
-import org.opensearch.OpenSearchStatusException;
 import org.opensearch.action.admin.indices.replication.SegmentReplicationStatsResponse;
 import org.opensearch.cluster.metadata.IndexMetadata;
 import org.opensearch.common.settings.Settings;
+import org.opensearch.index.SegmentReplicationPerGroupStats;
+import org.opensearch.index.SegmentReplicationShardStats;
+import org.opensearch.index.shard.IndexShard;
 import org.opensearch.indices.replication.common.ReplicationType;
 import org.opensearch.test.OpenSearchIntegTestCase;
 import org.opensearch.test.transport.MockTransportService;
 import org.opensearch.transport.TransportService;
 
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
 
@@ -54,22 +60,24 @@ public void testSegmentReplicationStatsResponse() throws Exception {
             SegmentReplicationStatsResponse segmentReplicationStatsResponse = dataNodeClient().admin()
                 .indices()
                 .prepareSegmentReplicationStats(INDEX_NAME)
+                .setDetailed(true)
                 .execute()
                 .actionGet();
-            assertEquals(segmentReplicationStatsResponse.shardSegmentReplicationStates().size(), 1);
+            SegmentReplicationPerGroupStats perGroupStats = segmentReplicationStatsResponse.getReplicationStats().get(INDEX_NAME).get(0);
+            final SegmentReplicationState currentReplicationState = perGroupStats.getReplicaStats()
+                .stream()
+                .findFirst()
+                .get()
+                .getCurrentReplicationState();
+            assertEquals(segmentReplicationStatsResponse.getReplicationStats().size(), 1);
             assertEquals(segmentReplicationStatsResponse.getTotalShards(), numShards * 2);
             assertEquals(segmentReplicationStatsResponse.getSuccessfulShards(), numShards * 2);
-            assertEquals(
-                segmentReplicationStatsResponse.shardSegmentReplicationStates().get(INDEX_NAME).get(0).getStage(),
-                SegmentReplicationState.Stage.DONE
-            );
-            assertTrue(
-                segmentReplicationStatsResponse.shardSegmentReplicationStates().get(INDEX_NAME).get(0).getIndex().recoveredFileCount() > 0
-            );
+            assertEquals(currentReplicationState.getStage(), SegmentReplicationState.Stage.DONE);
+            assertTrue(currentReplicationState.getIndex().recoveredFileCount() > 0);
         }, 1, TimeUnit.MINUTES);
     }
 
-    public void testSegmentReplicationStatsResponseForActiveAndCompletedOnly() throws Exception {
+    public void testSegmentReplicationStatsResponseForActiveOnly() throws Exception {
         final String primaryNode = internalCluster().startNode();
         createIndex(INDEX_NAME);
         ensureYellowAndNoInitializingShards(INDEX_NAME);
@@ -121,53 +129,231 @@ public void testSegmentReplicationStatsResponseForActiveAndCompletedOnly() throw
             .indices()
             .prepareSegmentReplicationStats(INDEX_NAME)
             .setActiveOnly(true)
+            .setDetailed(true)
             .execute()
             .actionGet();
-        assertEquals(
-            activeOnlyResponse.shardSegmentReplicationStates().get(INDEX_NAME).get(0).getStage(),
-            SegmentReplicationState.Stage.GET_FILES
+        SegmentReplicationPerGroupStats perGroupStats = activeOnlyResponse.getReplicationStats().get(INDEX_NAME).get(0);
+        SegmentReplicationState.Stage stage = perGroupStats.getReplicaStats()
+            .stream()
+            .findFirst()
+            .get()
+            .getCurrentReplicationState()
+            .getStage();
+        assertEquals(SegmentReplicationState.Stage.GET_FILES, stage);
+        waitForAssertions.countDown();
+    }
+
+    public void testNonDetailedResponse() throws Exception {
+        internalCluster().startClusterManagerOnlyNode();
+        int numReplicas = 4;
+        List<String> nodes = new ArrayList<>();
+        final String primaryNode = internalCluster().startNode();
+        nodes.add(primaryNode);
+        createIndex(
+            INDEX_NAME,
+            Settings.builder()
+                .put(indexSettings())
+                .put(IndexMetadata.SETTING_NUMBER_OF_SHARDS, 1)
+                .put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, numReplicas)
+                .build()
         );
+        ensureYellow(INDEX_NAME);
+        for (int i = 0; i < numReplicas; i++) {
+            nodes.add(internalCluster().startNode());
+        }
+        ensureGreen(INDEX_NAME);
+
+        final long numDocs = scaledRandomIntBetween(50, 100);
+        for (int i = 0; i < numDocs; i++) {
+            index(INDEX_NAME, "doc", Integer.toString(i));
+        }
+        refresh(INDEX_NAME);
+        waitForSearchableDocs(numDocs, nodes);
+
+        final IndexShard indexShard = getIndexShard(primaryNode, INDEX_NAME);
+
+        assertBusy(() -> {
+            SegmentReplicationStatsResponse segmentReplicationStatsResponse = dataNodeClient().admin()
+                .indices()
+                .prepareSegmentReplicationStats(INDEX_NAME)
+                .execute()
+                .actionGet();
 
-        // verifying completed_only by checking if current stage is DONE
-        SegmentReplicationStatsResponse completedOnlyResponse = client().admin()
+            final Map<String, List<SegmentReplicationPerGroupStats>> replicationStats = segmentReplicationStatsResponse
+                .getReplicationStats();
+            assertEquals(1, replicationStats.size());
+            final List<SegmentReplicationPerGroupStats> replicationPerGroupStats = replicationStats.get(INDEX_NAME);
+            assertEquals(1, replicationPerGroupStats.size());
+            final SegmentReplicationPerGroupStats perGroupStats = replicationPerGroupStats.get(0);
+            assertEquals(perGroupStats.getShardId(), indexShard.shardId());
+            final Set<SegmentReplicationShardStats> replicaStats = perGroupStats.getReplicaStats();
+            assertEquals(4, replicaStats.size());
+            for (SegmentReplicationShardStats replica : replicaStats) {
+                assertNotNull(replica.getCurrentReplicationState());
+            }
+        });
+    }
+
+    public void testGetSpecificShard() throws Exception {
+        internalCluster().startClusterManagerOnlyNode();
+        List<String> nodes = new ArrayList<>();
+        final String primaryNode = internalCluster().startNode();
+        nodes.add(primaryNode);
+        createIndex(
+            INDEX_NAME,
+            Settings.builder()
+                .put(indexSettings())
+                .put(IndexMetadata.SETTING_NUMBER_OF_SHARDS, 2)
+                .put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, 1)
+                .build()
+        );
+        ensureYellowAndNoInitializingShards(INDEX_NAME);
+        nodes.add(internalCluster().startNode());
+        ensureGreen(INDEX_NAME);
+
+        final long numDocs = scaledRandomIntBetween(50, 100);
+        for (int i = 0; i < numDocs; i++) {
+            index(INDEX_NAME, "doc", Integer.toString(i));
+        }
+        refresh(INDEX_NAME);
+        waitForSearchableDocs(numDocs, nodes);
+
+        final IndexShard indexShard = getIndexShard(primaryNode, INDEX_NAME);
+
+        // search for all
+        SegmentReplicationStatsResponse segmentReplicationStatsResponse = client().admin()
             .indices()
             .prepareSegmentReplicationStats(INDEX_NAME)
-            .setCompletedOnly(true)
+            .setActiveOnly(true)
             .execute()
             .actionGet();
-        assertEquals(completedOnlyResponse.shardSegmentReplicationStates().size(), SHARD_COUNT);
-        assertEquals(
-            completedOnlyResponse.shardSegmentReplicationStates().get(INDEX_NAME).get(0).getStage(),
-            SegmentReplicationState.Stage.DONE
-        );
-        assertTrue(completedOnlyResponse.shardSegmentReplicationStates().get(INDEX_NAME).get(0).getIndex().recoveredFileCount() > 0);
-        waitForAssertions.countDown();
+
+        Map<String, List<SegmentReplicationPerGroupStats>> replicationStats = segmentReplicationStatsResponse.getReplicationStats();
+        assertEquals(1, replicationStats.size());
+        List<SegmentReplicationPerGroupStats> replicationPerGroupStats = replicationStats.get(INDEX_NAME);
+        assertEquals(2, replicationPerGroupStats.size());
+        for (SegmentReplicationPerGroupStats group : replicationPerGroupStats) {
+            assertEquals(1, group.getReplicaStats().size());
+        }
+
+        // now search for one shard.
+        final int id = indexShard.shardId().getId();
+        segmentReplicationStatsResponse = client().admin()
+            .indices()
+            .prepareSegmentReplicationStats(INDEX_NAME)
+            .setActiveOnly(true)
+            .shards(String.valueOf(id))
+            .execute()
+            .actionGet();
+
+        replicationStats = segmentReplicationStatsResponse.getReplicationStats();
+        assertEquals(1, replicationStats.size());
+        replicationPerGroupStats = replicationStats.get(INDEX_NAME);
+        assertEquals(1, replicationPerGroupStats.size());
+        for (SegmentReplicationPerGroupStats group : replicationPerGroupStats) {
+            assertEquals(group.getShardId(), indexShard.shardId());
+            assertEquals(1, group.getReplicaStats().size());
+        }
+
     }
 
-    public void testSegmentReplicationStatsResponseOnDocumentReplicationIndex() {
+    public void testMultipleIndices() throws Exception {
+        internalCluster().startClusterManagerOnlyNode();
+        final String index_2 = "tst-index-2";
+        List<String> nodes = new ArrayList<>();
         final String primaryNode = internalCluster().startNode();
-        prepareCreate(
-            INDEX_NAME,
-            Settings.builder().put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.DOCUMENT)
+        nodes.add(primaryNode);
+        createIndex(INDEX_NAME, index_2);
+
+        ensureYellowAndNoInitializingShards(INDEX_NAME, index_2);
+        nodes.add(internalCluster().startNode());
+        ensureGreen(INDEX_NAME, index_2);
+
+        final long numDocs = scaledRandomIntBetween(50, 100);
+        for (int i = 0; i < numDocs; i++) {
+            index(INDEX_NAME, "doc", Integer.toString(i));
+            index(index_2, "doc", Integer.toString(i));
+        }
+        refresh(INDEX_NAME, index_2);
+        waitForSearchableDocs(INDEX_NAME, numDocs, nodes);
+        waitForSearchableDocs(index_2, numDocs, nodes);
+
+        final IndexShard index_1_primary = getIndexShard(primaryNode, INDEX_NAME);
+        final IndexShard index_2_primary = getIndexShard(primaryNode, index_2);
+
+        assertTrue(index_1_primary.routingEntry().primary());
+        assertTrue(index_2_primary.routingEntry().primary());
+
+        // test both indices are returned in the response.
+        SegmentReplicationStatsResponse segmentReplicationStatsResponse = client().admin()
+            .indices()
+            .prepareSegmentReplicationStats()
+            .execute()
+            .actionGet();
+
+        Map<String, List<SegmentReplicationPerGroupStats>> replicationStats = segmentReplicationStatsResponse.getReplicationStats();
+        assertEquals(2, replicationStats.size());
+        List<SegmentReplicationPerGroupStats> replicationPerGroupStats = replicationStats.get(INDEX_NAME);
+        assertEquals(1, replicationPerGroupStats.size());
+        SegmentReplicationPerGroupStats perGroupStats = replicationPerGroupStats.get(0);
+        assertEquals(perGroupStats.getShardId(), index_1_primary.shardId());
+        Set<SegmentReplicationShardStats> replicaStats = perGroupStats.getReplicaStats();
+        assertEquals(1, replicaStats.size());
+        for (SegmentReplicationShardStats replica : replicaStats) {
+            assertNotNull(replica.getCurrentReplicationState());
+        }
+
+        replicationPerGroupStats = replicationStats.get(index_2);
+        assertEquals(1, replicationPerGroupStats.size());
+        perGroupStats = replicationPerGroupStats.get(0);
+        assertEquals(perGroupStats.getShardId(), index_2_primary.shardId());
+        replicaStats = perGroupStats.getReplicaStats();
+        assertEquals(1, replicaStats.size());
+        for (SegmentReplicationShardStats replica : replicaStats) {
+            assertNotNull(replica.getCurrentReplicationState());
+        }
+
+        // test only single index queried.
+        segmentReplicationStatsResponse = client().admin()
+            .indices()
+            .prepareSegmentReplicationStats()
+            .setIndices(index_2)
+            .execute()
+            .actionGet();
+        assertEquals(1, segmentReplicationStatsResponse.getReplicationStats().size());
+        assertTrue(segmentReplicationStatsResponse.getReplicationStats().containsKey(index_2));
+    }
 
-        ).get();
+    public void testQueryAgainstDocRepIndex() {
+        internalCluster().startClusterManagerOnlyNode();
+        List<String> nodes = new ArrayList<>();
+        final String primaryNode = internalCluster().startNode();
+        nodes.add(primaryNode);
+        createIndex(
+            INDEX_NAME,
+            Settings.builder()
+                .put(indexSettings())
+                .put(IndexMetadata.SETTING_NUMBER_OF_SHARDS, 2)
+                .put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, 1)
+                .put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.DOCUMENT)
+                .build()
+        );
         ensureYellowAndNoInitializingShards(INDEX_NAME);
-        final String replicaNode = internalCluster().startNode();
+        nodes.add(internalCluster().startNode());
         ensureGreen(INDEX_NAME);
 
-        // index 10 docs
-        for (int i = 0; i < 10; i++) {
-            client().prepareIndex(INDEX_NAME).setId(Integer.toString(i)).setSource("field", "value" + i).execute().actionGet();
+        final long numDocs = scaledRandomIntBetween(50, 100);
+        for (int i = 0; i < numDocs; i++) {
+            index(INDEX_NAME, "doc", Integer.toString(i));
         }
         refresh(INDEX_NAME);
-        OpenSearchStatusException exception = assertThrows(
-            OpenSearchStatusException.class,
-            () -> client().admin().indices().prepareSegmentReplicationStats(INDEX_NAME).execute().actionGet()
-        );
-        // Verify exception message
-        String expectedMessage = "Segment Replication is not enabled on Index: test-idx-1";
-        assertEquals(expectedMessage, exception.getMessage());
 
+        // search for all
+        SegmentReplicationStatsResponse segmentReplicationStatsResponse = client().admin()
+            .indices()
+            .prepareSegmentReplicationStats(INDEX_NAME)
+            .execute()
+            .actionGet();
+        assertTrue(segmentReplicationStatsResponse.getReplicationStats().isEmpty());
     }
-
 }
diff --git a/server/src/internalClusterTest/java/org/opensearch/indices/settings/UpdateSettingsIT.java b/server/src/internalClusterTest/java/org/opensearch/indices/settings/UpdateSettingsIT.java
index 9970ff99a806c..6e94c50eec42a 100644
--- a/server/src/internalClusterTest/java/org/opensearch/indices/settings/UpdateSettingsIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/indices/settings/UpdateSettingsIT.java
@@ -136,11 +136,9 @@ public static class DummySettingPlugin extends Plugin {
 
         @Override
         public void onIndexModule(IndexModule indexModule) {
-            indexModule.addSettingsUpdateConsumer(
-                DUMMY_SETTING,
-                (s) -> {},
-                (s) -> { if (s.equals("boom")) throw new IllegalArgumentException("this setting goes boom"); }
-            );
+            indexModule.addSettingsUpdateConsumer(DUMMY_SETTING, (s) -> {}, (s) -> {
+                if (s.equals("boom")) throw new IllegalArgumentException("this setting goes boom");
+            });
         }
 
         @Override
diff --git a/server/src/internalClusterTest/java/org/opensearch/search/aggregations/metrics/CardinalityWithRequestBreakerIT.java b/server/src/internalClusterTest/java/org/opensearch/search/aggregations/metrics/CardinalityWithRequestBreakerIT.java
index e8d425596beb0..be69428453952 100644
--- a/server/src/internalClusterTest/java/org/opensearch/search/aggregations/metrics/CardinalityWithRequestBreakerIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/search/aggregations/metrics/CardinalityWithRequestBreakerIT.java
@@ -42,6 +42,7 @@
 import org.opensearch.search.aggregations.BucketOrder;
 import org.opensearch.test.OpenSearchIntegTestCase;
 
+import java.util.Map;
 import java.util.stream.IntStream;
 
 import static org.opensearch.search.aggregations.AggregationBuilders.cardinality;
@@ -62,7 +63,7 @@ public void testRequestBreaker() throws Exception {
                 .mapToObj(
                     i -> client().prepareIndex("test")
                         .setId("id_" + i)
-                        .setSource(org.opensearch.common.collect.Map.of("field0", randomAlphaOfLength(5), "field1", randomAlphaOfLength(5)))
+                        .setSource(Map.of("field0", randomAlphaOfLength(5), "field1", randomAlphaOfLength(5)))
                 )
                 .toArray(IndexRequestBuilder[]::new)
         );
diff --git a/server/src/internalClusterTest/java/org/opensearch/search/profile/aggregation/AggregationProfilerIT.java b/server/src/internalClusterTest/java/org/opensearch/search/profile/aggregation/AggregationProfilerIT.java
index f3d1a479f1b46..0e9e409efae59 100644
--- a/server/src/internalClusterTest/java/org/opensearch/search/profile/aggregation/AggregationProfilerIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/search/profile/aggregation/AggregationProfilerIT.java
@@ -69,7 +69,7 @@ public class AggregationProfilerIT extends OpenSearchIntegTestCase {
     private static final String INITIALIZE = AggregationTimingType.INITIALIZE.toString();
     private static final String BUILD_AGGREGATION = AggregationTimingType.BUILD_AGGREGATION.toString();
     private static final String REDUCE = AggregationTimingType.REDUCE.toString();
-    private static final Set<String> BREAKDOWN_KEYS = org.opensearch.common.collect.Set.of(
+    private static final Set<String> BREAKDOWN_KEYS = Set.of(
         INITIALIZE,
         BUILD_LEAF_COLLECTOR,
         COLLECT,
@@ -107,7 +107,7 @@ protected void setupSuiteScopeCluster() throws Exception {
             client().admin()
                 .indices()
                 .prepareCreate("idx")
-                .setSettings(org.opensearch.common.collect.Map.of("number_of_shards", 1, "number_of_replicas", 0))
+                .setSettings(Map.of("number_of_shards", 1, "number_of_replicas", 0))
                 .setMapping(STRING_FIELD, "type=keyword", NUMBER_FIELD, "type=integer", TAG_FIELD, "type=keyword")
                 .get()
         );
@@ -166,7 +166,7 @@ public void testSimpleProfile() {
             assertThat(breakdown.get(REDUCE), equalTo(0L));
             Map<String, Object> debug = histoAggResult.getDebugInfo();
             assertThat(debug, notNullValue());
-            assertThat(debug.keySet(), equalTo(org.opensearch.common.collect.Set.of(TOTAL_BUCKETS)));
+            assertThat(debug.keySet(), equalTo(Set.of(TOTAL_BUCKETS)));
             assertThat(((Number) debug.get(TOTAL_BUCKETS)).longValue(), greaterThan(0L));
         }
     }
@@ -209,7 +209,7 @@ public void testMultiLevelProfile() {
             assertThat(histoBreakdown.get(REDUCE), equalTo(0L));
             Map<String, Object> histoDebugInfo = histoAggResult.getDebugInfo();
             assertThat(histoDebugInfo, notNullValue());
-            assertThat(histoDebugInfo.keySet(), equalTo(org.opensearch.common.collect.Set.of(TOTAL_BUCKETS)));
+            assertThat(histoDebugInfo.keySet(), equalTo(Set.of(TOTAL_BUCKETS)));
             assertThat(((Number) histoDebugInfo.get(TOTAL_BUCKETS)).longValue(), greaterThan(0L));
             assertThat(histoAggResult.getProfiledChildren().size(), equalTo(1));
 
@@ -240,7 +240,7 @@ public void testMultiLevelProfile() {
             assertThat(avgBreakdown.get(COLLECT), greaterThan(0L));
             assertThat(avgBreakdown.get(BUILD_AGGREGATION), greaterThan(0L));
             assertThat(avgBreakdown.get(REDUCE), equalTo(0L));
-            assertThat(avgAggResult.getDebugInfo(), equalTo(org.opensearch.common.collect.Map.of()));
+            assertThat(avgAggResult.getDebugInfo(), equalTo(Map.of()));
             assertThat(avgAggResult.getProfiledChildren().size(), equalTo(0));
         }
     }
@@ -295,7 +295,7 @@ public void testMultiLevelProfileBreadthFirst() {
             assertThat(histoBreakdown.get(REDUCE), equalTo(0L));
             Map<String, Object> histoDebugInfo = histoAggResult.getDebugInfo();
             assertThat(histoDebugInfo, notNullValue());
-            assertThat(histoDebugInfo.keySet(), equalTo(org.opensearch.common.collect.Set.of(TOTAL_BUCKETS)));
+            assertThat(histoDebugInfo.keySet(), equalTo(Set.of(TOTAL_BUCKETS)));
             assertThat(((Number) histoDebugInfo.get(TOTAL_BUCKETS)).longValue(), greaterThan(0L));
             assertThat(histoAggResult.getProfiledChildren().size(), equalTo(1));
 
@@ -326,7 +326,7 @@ public void testMultiLevelProfileBreadthFirst() {
             assertThat(avgBreakdown.get(COLLECT), greaterThan(0L));
             assertThat(avgBreakdown.get(BUILD_AGGREGATION), greaterThan(0L));
             assertThat(avgBreakdown.get(REDUCE), equalTo(0L));
-            assertThat(avgAggResult.getDebugInfo(), equalTo(org.opensearch.common.collect.Map.of()));
+            assertThat(avgAggResult.getDebugInfo(), equalTo(Map.of()));
             assertThat(avgAggResult.getProfiledChildren().size(), equalTo(0));
         }
     }
@@ -366,10 +366,7 @@ public void testDiversifiedAggProfile() {
             assertThat(diversifyBreakdown.get(POST_COLLECTION), greaterThan(0L));
             assertThat(diversifyBreakdown.get(BUILD_AGGREGATION), greaterThan(0L));
             assertThat(diversifyBreakdown.get(REDUCE), equalTo(0L));
-            assertThat(
-                diversifyAggResult.getDebugInfo(),
-                equalTo(org.opensearch.common.collect.Map.of(DEFERRED, org.opensearch.common.collect.List.of("max")))
-            );
+            assertThat(diversifyAggResult.getDebugInfo(), equalTo(Map.of(DEFERRED, List.of("max"))));
             assertThat(diversifyAggResult.getProfiledChildren().size(), equalTo(1));
 
             ProfileResult maxAggResult = diversifyAggResult.getProfiledChildren().get(0);
@@ -386,7 +383,7 @@ public void testDiversifiedAggProfile() {
             assertThat(diversifyBreakdown.get(POST_COLLECTION), greaterThan(0L));
             assertThat(maxBreakdown.get(BUILD_AGGREGATION), greaterThan(0L));
             assertThat(maxBreakdown.get(REDUCE), equalTo(0L));
-            assertThat(maxAggResult.getDebugInfo(), equalTo(org.opensearch.common.collect.Map.of()));
+            assertThat(maxAggResult.getDebugInfo(), equalTo(Map.of()));
             assertThat(maxAggResult.getProfiledChildren().size(), equalTo(0));
         }
     }
@@ -441,7 +438,7 @@ public void testComplexProfile() {
             assertThat(histoBreakdown.get(REDUCE), equalTo(0L));
             Map<String, Object> histoDebugInfo = histoAggResult.getDebugInfo();
             assertThat(histoDebugInfo, notNullValue());
-            assertThat(histoDebugInfo.keySet(), equalTo(org.opensearch.common.collect.Set.of(TOTAL_BUCKETS)));
+            assertThat(histoDebugInfo.keySet(), equalTo(Set.of(TOTAL_BUCKETS)));
             assertThat(((Number) histoDebugInfo.get(TOTAL_BUCKETS)).longValue(), greaterThan(0L));
             assertThat(histoAggResult.getProfiledChildren().size(), equalTo(2));
 
@@ -482,7 +479,7 @@ public void testComplexProfile() {
             assertThat(avgBreakdown.get(POST_COLLECTION), greaterThan(0L));
             assertThat(avgBreakdown.get(BUILD_AGGREGATION), greaterThan(0L));
             assertThat(avgBreakdown.get(REDUCE), equalTo(0L));
-            assertThat(avgAggResult.getDebugInfo(), equalTo(org.opensearch.common.collect.Map.of()));
+            assertThat(avgAggResult.getDebugInfo(), equalTo(Map.of()));
             assertThat(avgAggResult.getProfiledChildren().size(), equalTo(0));
 
             ProfileResult maxAggResult = tagsAggResultSubAggregations.get("max");
@@ -498,7 +495,7 @@ public void testComplexProfile() {
             assertThat(maxBreakdown.get(POST_COLLECTION), greaterThan(0L));
             assertThat(maxBreakdown.get(BUILD_AGGREGATION), greaterThan(0L));
             assertThat(maxBreakdown.get(REDUCE), equalTo(0L));
-            assertThat(maxAggResult.getDebugInfo(), equalTo(org.opensearch.common.collect.Map.of()));
+            assertThat(maxAggResult.getDebugInfo(), equalTo(Map.of()));
             assertThat(maxAggResult.getProfiledChildren().size(), equalTo(0));
 
             ProfileResult stringsAggResult = histoAggResultSubAggregations.get("strings");
@@ -534,7 +531,7 @@ public void testComplexProfile() {
             assertThat(avgBreakdown.get(POST_COLLECTION), greaterThan(0L));
             assertThat(avgBreakdown.get(BUILD_AGGREGATION), greaterThan(0L));
             assertThat(avgBreakdown.get(REDUCE), equalTo(0L));
-            assertThat(avgAggResult.getDebugInfo(), equalTo(org.opensearch.common.collect.Map.of()));
+            assertThat(avgAggResult.getDebugInfo(), equalTo(Map.of()));
             assertThat(avgAggResult.getProfiledChildren().size(), equalTo(0));
 
             maxAggResult = stringsAggResultSubAggregations.get("max");
@@ -550,7 +547,7 @@ public void testComplexProfile() {
             assertThat(maxBreakdown.get(POST_COLLECTION), greaterThan(0L));
             assertThat(maxBreakdown.get(BUILD_AGGREGATION), greaterThan(0L));
             assertThat(maxBreakdown.get(REDUCE), equalTo(0L));
-            assertThat(maxAggResult.getDebugInfo(), equalTo(org.opensearch.common.collect.Map.of()));
+            assertThat(maxAggResult.getDebugInfo(), equalTo(Map.of()));
             assertThat(maxAggResult.getProfiledChildren().size(), equalTo(0));
 
             tagsAggResult = stringsAggResultSubAggregations.get("tags");
@@ -587,7 +584,7 @@ public void testComplexProfile() {
             assertThat(avgBreakdown.get(POST_COLLECTION), greaterThan(0L));
             assertThat(avgBreakdown.get(BUILD_AGGREGATION), greaterThan(0L));
             assertThat(avgBreakdown.get(REDUCE), equalTo(0L));
-            assertThat(avgAggResult.getDebugInfo(), equalTo(org.opensearch.common.collect.Map.of()));
+            assertThat(avgAggResult.getDebugInfo(), equalTo(Map.of()));
             assertThat(avgAggResult.getProfiledChildren().size(), equalTo(0));
 
             maxAggResult = tagsAggResultSubAggregations.get("max");
@@ -603,7 +600,7 @@ public void testComplexProfile() {
             assertThat(maxBreakdown.get(POST_COLLECTION), greaterThan(0L));
             assertThat(maxBreakdown.get(BUILD_AGGREGATION), greaterThan(0L));
             assertThat(maxBreakdown.get(REDUCE), equalTo(0L));
-            assertThat(maxAggResult.getDebugInfo(), equalTo(org.opensearch.common.collect.Map.of()));
+            assertThat(maxAggResult.getDebugInfo(), equalTo(Map.of()));
             assertThat(maxAggResult.getProfiledChildren().size(), equalTo(0));
         }
     }
diff --git a/server/src/internalClusterTest/java/org/opensearch/snapshots/SearchableSnapshotIT.java b/server/src/internalClusterTest/java/org/opensearch/snapshots/SearchableSnapshotIT.java
index b969c0c4b8e24..5f5e0a0912140 100644
--- a/server/src/internalClusterTest/java/org/opensearch/snapshots/SearchableSnapshotIT.java
+++ b/server/src/internalClusterTest/java/org/opensearch/snapshots/SearchableSnapshotIT.java
@@ -15,6 +15,7 @@
 import org.opensearch.action.admin.cluster.snapshots.restore.RestoreSnapshotRequest;
 import org.opensearch.action.admin.indices.settings.put.UpdateSettingsRequestBuilder;
 import org.opensearch.action.index.IndexRequestBuilder;
+import org.opensearch.action.search.SearchResponse;
 import org.opensearch.action.support.master.AcknowledgedResponse;
 import org.opensearch.client.Client;
 import org.opensearch.cluster.ClusterState;
@@ -23,21 +24,27 @@
 import org.opensearch.cluster.routing.GroupShardsIterator;
 import org.opensearch.cluster.routing.ShardIterator;
 import org.opensearch.cluster.routing.ShardRouting;
-import org.opensearch.common.collect.Map;
 import org.opensearch.common.io.PathUtils;
 import org.opensearch.common.settings.Settings;
 import org.opensearch.common.unit.ByteSizeUnit;
 import org.opensearch.common.util.FeatureFlags;
+import org.opensearch.env.NodeEnvironment;
 import org.opensearch.index.Index;
 import org.opensearch.index.IndexNotFoundException;
+import org.opensearch.index.query.QueryBuilders;
 import org.opensearch.index.store.remote.file.CleanerDaemonThreadLeakFilter;
 import org.opensearch.index.store.remote.filecache.FileCacheStats;
 import org.opensearch.monitor.fs.FsInfo;
 import org.opensearch.repositories.fs.FsRepository;
 
+import java.io.IOException;
 import java.nio.file.Files;
+import java.nio.file.NoSuchFileException;
 import java.nio.file.Path;
+import java.nio.file.StandardCopyOption;
 import java.util.List;
+import java.util.Map;
+import java.util.stream.Stream;
 
 import static org.hamcrest.Matchers.contains;
 import static org.hamcrest.Matchers.equalTo;
@@ -46,6 +53,7 @@
 import static org.hamcrest.Matchers.notNullValue;
 import static org.opensearch.action.admin.cluster.node.stats.NodesStatsRequest.Metric.FS;
 import static org.opensearch.common.util.CollectionUtils.iterableAsArrayList;
+import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertHitCount;
 
 @ThreadLeakFilters(filters = CleanerDaemonThreadLeakFilter.class)
 public final class SearchableSnapshotIT extends AbstractSnapshotIntegTestCase {
@@ -64,13 +72,14 @@ protected Settings featureFlagSettings() {
     protected Settings.Builder randomRepositorySettings() {
         final Settings.Builder settings = Settings.builder();
         settings.put("location", randomRepoPath()).put("compress", randomBoolean());
+        settings.put(FsRepository.BASE_PATH_SETTING.getKey(), "my_base_path");
         return settings;
     }
 
     private Settings.Builder chunkedRepositorySettings() {
         final Settings.Builder settings = Settings.builder();
         settings.put("location", randomRepoPath()).put("compress", randomBoolean());
-        settings.put("chunk_size", 2 << 13, ByteSizeUnit.BYTES);
+        settings.put("chunk_size", 2 << 23, ByteSizeUnit.BYTES);
         return settings;
     }
 
@@ -379,6 +388,71 @@ private void testUpdateIndexSettingsAtLeastOneNotAllowedSettings(String index) {
         }
     }
 
+    public void testFileCacheStats() throws Exception {
+        final String snapshotName = "test-snap";
+        final String repoName = "test-repo";
+        final String indexName1 = "test-idx-1";
+        final Client client = client();
+        final int numNodes = 2;
+
+        internalCluster().ensureAtLeastNumDataNodes(numNodes);
+        createIndexWithDocsAndEnsureGreen(1, 100, indexName1);
+
+        createRepositoryWithSettings(null, repoName);
+        takeSnapshot(client, snapshotName, repoName, indexName1);
+        deleteIndicesAndEnsureGreen(client, indexName1);
+        assertAllNodesFileCacheEmpty();
+
+        internalCluster().ensureAtLeastNumSearchNodes(numNodes);
+        restoreSnapshotAndEnsureGreen(client, snapshotName, repoName);
+        assertNodesFileCacheNonEmpty(numNodes);
+    }
+
+    /**
+     * Tests file cache restore scenario for searchable snapshots by creating an index,
+     * taking a snapshot, restoring it as a searchable snapshot.
+     * It ensures file cache is restored post node restart.
+     */
+    public void testFileCacheRestore() throws Exception {
+        final String snapshotName = "test-snap";
+        final String repoName = "test-repo";
+        final String indexName = "test-idx";
+        final String restoredIndexName = indexName + "-copy";
+        // Keeping the replicas to 0 for reproducible cache results as shards can get reassigned otherwise
+        final int numReplicasIndex = 0;
+        final Client client = client();
+
+        internalCluster().ensureAtLeastNumDataNodes(numReplicasIndex + 1);
+        createIndexWithDocsAndEnsureGreen(numReplicasIndex, 100, indexName);
+
+        createRepositoryWithSettings(null, repoName);
+        takeSnapshot(client, snapshotName, repoName, indexName);
+        deleteIndicesAndEnsureGreen(client, indexName);
+
+        internalCluster().ensureAtLeastNumSearchNodes(numReplicasIndex + 1);
+        restoreSnapshotAndEnsureGreen(client, snapshotName, repoName);
+        assertDocCount(restoredIndexName, 100L);
+        assertIndexDirectoryDoesNotExist(restoredIndexName);
+
+        NodesStatsResponse preRestoreStats = client().admin().cluster().nodesStats(new NodesStatsRequest().all()).actionGet();
+        for (NodeStats nodeStats : preRestoreStats.getNodes()) {
+            if (nodeStats.getNode().isSearchNode()) {
+                internalCluster().restartNode(nodeStats.getNode().getName());
+            }
+        }
+
+        NodesStatsResponse postRestoreStats = client().admin().cluster().nodesStats(new NodesStatsRequest().all()).actionGet();
+        Map<String, NodeStats> preRestoreStatsMap = preRestoreStats.getNodesMap();
+        Map<String, NodeStats> postRestoreStatsMap = postRestoreStats.getNodesMap();
+        for (String node : postRestoreStatsMap.keySet()) {
+            NodeStats preRestoreStat = preRestoreStatsMap.get(node);
+            NodeStats postRestoreStat = postRestoreStatsMap.get(node);
+            if (preRestoreStat.getNode().isSearchNode()) {
+                assertEquals(preRestoreStat.getFileCacheStats().getUsed(), postRestoreStat.getFileCacheStats().getUsed());
+            }
+        }
+    }
+
     /**
      * Picks a shard out of the cluster state for each given index and asserts
      * that the 'index' directory does not exist in the node's file system.
@@ -417,26 +491,6 @@ private void assertIndexDirectoryDoesNotExist(String... indexNames) {
         }
     }
 
-    public void testFileCacheStats() throws Exception {
-        final String snapshotName = "test-snap";
-        final String repoName = "test-repo";
-        final String indexName1 = "test-idx-1";
-        final Client client = client();
-        final int numNodes = 2;
-
-        internalCluster().ensureAtLeastNumDataNodes(numNodes);
-        createIndexWithDocsAndEnsureGreen(1, 100, indexName1);
-
-        createRepositoryWithSettings(null, repoName);
-        takeSnapshot(client, snapshotName, repoName, indexName1);
-        deleteIndicesAndEnsureGreen(client, indexName1);
-        assertAllNodesFileCacheEmpty();
-
-        internalCluster().ensureAtLeastNumSearchNodes(numNodes);
-        restoreSnapshotAndEnsureGreen(client, snapshotName, repoName);
-        assertNodesFileCacheNonEmpty(numNodes);
-    }
-
     private void assertAllNodesFileCacheEmpty() {
         NodesStatsResponse response = client().admin().cluster().nodesStats(new NodesStatsRequest().all()).actionGet();
         for (NodeStats stats : response.getNodes()) {
@@ -468,6 +522,7 @@ private boolean isFileCacheEmpty(FileCacheStats stats) {
         return stats.getUsed().getBytes() == 0L && stats.getActive().getBytes() == 0L;
     }
 
+    @AwaitsFix(bugUrl = "https://github.com/opensearch-project/OpenSearch/issues/6738")
     public void testPruneFileCacheOnIndexDeletion() throws Exception {
         final String snapshotName = "test-snap";
         final String repoName = "test-repo";
@@ -489,4 +544,48 @@ public void testPruneFileCacheOnIndexDeletion() throws Exception {
         deleteIndicesAndEnsureGreen(client, restoredIndexName1);
         assertAllNodesFileCacheEmpty();
     }
+
+    @AwaitsFix(bugUrl = "https://github.com/opensearch-project/OpenSearch/issues/6686")
+    public void testCacheFilesAreClosedAfterUse() throws Exception {
+        final int numReplicasIndex = randomIntBetween(1, 4);
+        final String indexName = "test-idx";
+        final String restoredIndexName = indexName + "-copy";
+        final String repoName = "test-repo";
+        final String snapshotName = "test-snap";
+        final String id = randomAlphaOfLength(5);
+        final Client client = client();
+
+        internalCluster().ensureAtLeastNumSearchAndDataNodes(numReplicasIndex + 1);
+        createIndex(indexName);
+        client().prepareIndex(indexName).setId(id).setSource("field", "test").get();
+        ensureGreen();
+        createRepositoryWithSettings(null, repoName);
+        takeSnapshot(client, snapshotName, repoName, indexName);
+        restoreSnapshotAndEnsureGreen(client, snapshotName, repoName);
+
+        // Search document to make the index fetch data from the remote snapshot to local storage
+        SearchResponse searchResponse = client().prepareSearch(restoredIndexName).setQuery(QueryBuilders.termQuery("field", "test")).get();
+        assertHitCount(searchResponse, 1);
+
+        // The local cache files should be closed by deleting the restored index
+        deleteIndicesAndEnsureGreen(client, restoredIndexName);
+
+        logger.info("--> validate all the cache files are closed");
+        // Get path of cache files
+        final NodeEnvironment nodeEnv = internalCluster().getInstance(NodeEnvironment.class);
+        Path fileCachePath = nodeEnv.fileCacheNodePath().fileCachePath;
+        // Find all the files in the path
+        try (Stream<Path> paths = Files.walk(fileCachePath)) {
+            paths.filter(Files::isRegularFile).forEach(path -> {
+                // Testing moving the file to check the file is closed or not.
+                try {
+                    Files.move(path, path, StandardCopyOption.REPLACE_EXISTING);
+                } catch (IOException e) {
+                    fail("No exception is expected. The file can't be moved, so it may not be closed.");
+                }
+            });
+        } catch (NoSuchFileException e) {
+            logger.debug("--> the path for the cache files doesn't exist");
+        }
+    }
 }
diff --git a/server/src/main/java/org/opensearch/Version.java b/server/src/main/java/org/opensearch/Version.java
index 4eba5a591d8f9..8a6e209a1fbc5 100644
--- a/server/src/main/java/org/opensearch/Version.java
+++ b/server/src/main/java/org/opensearch/Version.java
@@ -93,6 +93,7 @@ public class Version implements Comparable<Version>, ToXContentFragment {
     public static final Version V_1_3_7 = new Version(1030799, org.apache.lucene.util.Version.LUCENE_8_10_1);
     public static final Version V_1_3_8 = new Version(1030899, org.apache.lucene.util.Version.LUCENE_8_10_1);
     public static final Version V_1_3_9 = new Version(1030999, org.apache.lucene.util.Version.LUCENE_8_10_1);
+    public static final Version V_1_3_10 = new Version(1031099, org.apache.lucene.util.Version.LUCENE_8_10_1);
     public static final Version V_2_0_0 = new Version(2000099, org.apache.lucene.util.Version.LUCENE_9_1_0);
     public static final Version V_2_0_1 = new Version(2000199, org.apache.lucene.util.Version.LUCENE_9_1_0);
     public static final Version V_2_0_2 = new Version(2000299, org.apache.lucene.util.Version.LUCENE_9_1_0);
@@ -109,6 +110,7 @@ public class Version implements Comparable<Version>, ToXContentFragment {
     public static final Version V_2_5_0 = new Version(2050099, org.apache.lucene.util.Version.LUCENE_9_4_2);
     public static final Version V_2_5_1 = new Version(2050199, org.apache.lucene.util.Version.LUCENE_9_4_2);
     public static final Version V_2_6_0 = new Version(2060099, org.apache.lucene.util.Version.LUCENE_9_5_0);
+    public static final Version V_2_6_1 = new Version(2060199, org.apache.lucene.util.Version.LUCENE_9_5_0);
     public static final Version V_2_7_0 = new Version(2070099, org.apache.lucene.util.Version.LUCENE_9_5_0);
     public static final Version CURRENT = V_2_7_0;
 
diff --git a/server/src/main/java/org/opensearch/action/admin/cluster/health/TransportClusterHealthAction.java b/server/src/main/java/org/opensearch/action/admin/cluster/health/TransportClusterHealthAction.java
index 42758b845093f..d475826b059d8 100644
--- a/server/src/main/java/org/opensearch/action/admin/cluster/health/TransportClusterHealthAction.java
+++ b/server/src/main/java/org/opensearch/action/admin/cluster/health/TransportClusterHealthAction.java
@@ -62,6 +62,7 @@
 import org.opensearch.common.io.stream.StreamInput;
 import org.opensearch.common.unit.TimeValue;
 import org.opensearch.common.util.CollectionUtils;
+import org.opensearch.discovery.ClusterManagerNotDiscoveredException;
 import org.opensearch.discovery.Discovery;
 import org.opensearch.index.IndexNotFoundException;
 import org.opensearch.node.NodeClosedException;
@@ -279,15 +280,20 @@ private void executeHealth(
         final Predicate<ClusterState> validationPredicate = newState -> validateRequest(request, newState, waitCount);
         if (validationPredicate.test(currentState)) {
             ClusterHealthResponse clusterHealthResponse = getResponse(request, currentState, waitCount, TimeoutState.OK);
-            if (request.ensureNodeWeighedIn() && clusterHealthResponse.hasDiscoveredClusterManager()) {
-                DiscoveryNode localNode = currentState.getNodes().getLocalNode();
-                // TODO: make this check more generic, check for node role instead
-                if (localNode.isDataNode()) {
-                    assert request.local() == true : "local node request false for request for local node weighed in";
-                    boolean weighedAway = WeightedRoutingUtils.isWeighedAway(localNode.getId(), currentState);
-                    if (weighedAway) {
-                        listener.onFailure(new NodeWeighedAwayException("local node is weighed away"));
-                        return;
+            if (request.ensureNodeWeighedIn()) {
+                if (clusterHealthResponse.hasDiscoveredClusterManager() == false) {
+                    listener.onFailure(new ClusterManagerNotDiscoveredException("cluster-manager not discovered"));
+                    return;
+                } else {
+                    DiscoveryNode localNode = currentState.getNodes().getLocalNode();
+                    // TODO: make this check more generic, check for node role instead
+                    if (localNode.isDataNode()) {
+                        assert request.local() == true : "local node request false for request for local node weighed in";
+                        boolean weighedAway = WeightedRoutingUtils.isWeighedAway(localNode.getId(), currentState);
+                        if (weighedAway) {
+                            listener.onFailure(new NodeWeighedAwayException("local node is weighed away"));
+                            return;
+                        }
                     }
                 }
             }
diff --git a/server/src/main/java/org/opensearch/action/admin/cluster/settings/ClusterUpdateSettingsResponse.java b/server/src/main/java/org/opensearch/action/admin/cluster/settings/ClusterUpdateSettingsResponse.java
index a4edd1d99148a..4643853e4494b 100644
--- a/server/src/main/java/org/opensearch/action/admin/cluster/settings/ClusterUpdateSettingsResponse.java
+++ b/server/src/main/java/org/opensearch/action/admin/cluster/settings/ClusterUpdateSettingsResponse.java
@@ -59,7 +59,9 @@ public class ClusterUpdateSettingsResponse extends AcknowledgedResponse {
     private static final ConstructingObjectParser<ClusterUpdateSettingsResponse, Void> PARSER = new ConstructingObjectParser<>(
         "cluster_update_settings_response",
         true,
-        args -> { return new ClusterUpdateSettingsResponse((boolean) args[0], (Settings) args[1], (Settings) args[2]); }
+        args -> {
+            return new ClusterUpdateSettingsResponse((boolean) args[0], (Settings) args[1], (Settings) args[2]);
+        }
     );
     static {
         declareAcknowledgedField(PARSER);
diff --git a/server/src/main/java/org/opensearch/action/admin/cluster/shards/routing/weighted/put/TransportAddWeightedRoutingAction.java b/server/src/main/java/org/opensearch/action/admin/cluster/shards/routing/weighted/put/TransportAddWeightedRoutingAction.java
index 249e313c1f53b..56203d4edc3d0 100644
--- a/server/src/main/java/org/opensearch/action/admin/cluster/shards/routing/weighted/put/TransportAddWeightedRoutingAction.java
+++ b/server/src/main/java/org/opensearch/action/admin/cluster/shards/routing/weighted/put/TransportAddWeightedRoutingAction.java
@@ -81,12 +81,9 @@ protected void clusterManagerOperation(
         }
         weightedRoutingService.registerWeightedRoutingMetadata(
             request,
-            ActionListener.delegateFailure(
-                listener,
-                (delegatedListener, response) -> {
-                    delegatedListener.onResponse(new ClusterPutWeightedRoutingResponse(response.isAcknowledged()));
-                }
-            )
+            ActionListener.delegateFailure(listener, (delegatedListener, response) -> {
+                delegatedListener.onResponse(new ClusterPutWeightedRoutingResponse(response.isAcknowledged()));
+            })
         );
     }
 
diff --git a/server/src/main/java/org/opensearch/action/admin/indices/create/AutoCreateAction.java b/server/src/main/java/org/opensearch/action/admin/indices/create/AutoCreateAction.java
index 77f09f02c9a9c..556d46683f0ab 100644
--- a/server/src/main/java/org/opensearch/action/admin/indices/create/AutoCreateAction.java
+++ b/server/src/main/java/org/opensearch/action/admin/indices/create/AutoCreateAction.java
@@ -132,7 +132,9 @@ protected void clusterManagerOperation(
                         new String[] { indexName },
                         ActiveShardCount.DEFAULT,
                         request.timeout(),
-                        shardsAcked -> { finalListener.onResponse(new CreateIndexResponse(true, shardsAcked, indexName)); },
+                        shardsAcked -> {
+                            finalListener.onResponse(new CreateIndexResponse(true, shardsAcked, indexName));
+                        },
                         finalListener::onFailure
                     );
                 } else {
diff --git a/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationShardStatsResponse.java b/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationShardStatsResponse.java
new file mode 100644
index 0000000000000..b6855507669b6
--- /dev/null
+++ b/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationShardStatsResponse.java
@@ -0,0 +1,67 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.action.admin.indices.replication;
+
+import org.opensearch.common.Nullable;
+import org.opensearch.common.io.stream.StreamInput;
+import org.opensearch.common.io.stream.StreamOutput;
+import org.opensearch.common.io.stream.Writeable;
+import org.opensearch.index.SegmentReplicationPerGroupStats;
+import org.opensearch.indices.replication.SegmentReplicationState;
+
+import java.io.IOException;
+
+/**
+ * Segment Replication specific response object for fetching stats from either a primary
+ * or replica shard. The stats returned are different depending on primary or replica.
+ *
+ * @opensearch.internal
+ */
+public class SegmentReplicationShardStatsResponse implements Writeable {
+
+    @Nullable
+    private final SegmentReplicationPerGroupStats primaryStats;
+
+    @Nullable
+    private final SegmentReplicationState replicaStats;
+
+    public SegmentReplicationShardStatsResponse(StreamInput in) throws IOException {
+        this.primaryStats = in.readOptionalWriteable(SegmentReplicationPerGroupStats::new);
+        this.replicaStats = in.readOptionalWriteable(SegmentReplicationState::new);
+    }
+
+    public SegmentReplicationShardStatsResponse(SegmentReplicationPerGroupStats primaryStats) {
+        this.primaryStats = primaryStats;
+        this.replicaStats = null;
+    }
+
+    public SegmentReplicationShardStatsResponse(SegmentReplicationState replicaStats) {
+        this.replicaStats = replicaStats;
+        this.primaryStats = null;
+    }
+
+    public SegmentReplicationPerGroupStats getPrimaryStats() {
+        return primaryStats;
+    }
+
+    public SegmentReplicationState getReplicaStats() {
+        return replicaStats;
+    }
+
+    @Override
+    public void writeTo(StreamOutput out) throws IOException {
+        out.writeOptionalWriteable(primaryStats);
+        out.writeOptionalWriteable(replicaStats);
+    }
+
+    @Override
+    public String toString() {
+        return "SegmentReplicationShardStatsResponse{" + "primaryStats=" + primaryStats + ", replicaStats=" + replicaStats + '}';
+    }
+}
diff --git a/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationStatsRequest.java b/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationStatsRequest.java
index fdd29990fb446..1142bf697db27 100644
--- a/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationStatsRequest.java
+++ b/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationStatsRequest.java
@@ -24,11 +24,8 @@
 public class SegmentReplicationStatsRequest extends BroadcastRequest<SegmentReplicationStatsRequest> {
     private boolean detailed = false;       // Provides extra details in the response
     private boolean activeOnly = false;     // Only reports on active segment replication events
-
     private String[] shards = new String[0];
 
-    private boolean completedOnly = false;
-
     /**
      * Constructs a request for segment replication stats information for all shards
      */
@@ -40,8 +37,6 @@ public SegmentReplicationStatsRequest(StreamInput in) throws IOException {
         super(in);
         detailed = in.readBoolean();
         activeOnly = in.readBoolean();
-        completedOnly = in.readBoolean();
-
     }
 
     /**
@@ -91,25 +86,6 @@ public void activeOnly(boolean activeOnly) {
         this.activeOnly = activeOnly;
     }
 
-    /**
-     * True if completedOnly flag is set, false otherwise. This value is false by default.
-     *
-     * @return  True if completedOnly flag is set, false otherwise
-     */
-    public boolean completedOnly() {
-        return completedOnly;
-    }
-
-    /**
-     * Set value of the completedOnly flag. If true, this request will only respond with
-     * latest completed segment replication event information.
-     *
-     * @param completedOnly   Whether or not to set the completedOnly flag.
-     */
-    public void completedOnly(boolean completedOnly) {
-        this.completedOnly = completedOnly;
-    }
-
     /**
      * Contains list of shard id's if shards are passed, empty otherwise. Array is empty by default.
      *
@@ -134,6 +110,5 @@ public void writeTo(StreamOutput out) throws IOException {
         super.writeTo(out);
         out.writeBoolean(detailed);
         out.writeBoolean(activeOnly);
-        out.writeBoolean(completedOnly);
     }
 }
diff --git a/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationStatsRequestBuilder.java b/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationStatsRequestBuilder.java
index abd48cfe0ba4f..7e68d2ac59f07 100644
--- a/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationStatsRequestBuilder.java
+++ b/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationStatsRequestBuilder.java
@@ -35,11 +35,6 @@ public SegmentReplicationStatsRequestBuilder setActiveOnly(boolean activeOnly) {
         return this;
     }
 
-    public SegmentReplicationStatsRequestBuilder setCompletedOnly(boolean completedOnly) {
-        request.completedOnly(completedOnly);
-        return this;
-    }
-
     public SegmentReplicationStatsRequestBuilder shards(String... indices) {
         request.shards(indices);
         return this;
diff --git a/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationStatsResponse.java b/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationStatsResponse.java
index 2f72d7dd3e544..a72455be3713a 100644
--- a/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationStatsResponse.java
+++ b/server/src/main/java/org/opensearch/action/admin/indices/replication/SegmentReplicationStatsResponse.java
@@ -15,7 +15,7 @@
 import org.opensearch.common.io.stream.StreamOutput;
 import org.opensearch.common.xcontent.XContentBuilder;
 import org.opensearch.common.xcontent.XContentType;
-import org.opensearch.indices.replication.SegmentReplicationState;
+import org.opensearch.index.SegmentReplicationPerGroupStats;
 
 import java.io.IOException;
 import java.util.List;
@@ -27,54 +27,50 @@
  * @opensearch.internal
  */
 public class SegmentReplicationStatsResponse extends BroadcastResponse {
-    private final Map<String, List<SegmentReplicationState>> shardSegmentReplicationStates;
+    private final Map<String, List<SegmentReplicationPerGroupStats>> replicationStats;
 
     public SegmentReplicationStatsResponse(StreamInput in) throws IOException {
         super(in);
-        shardSegmentReplicationStates = in.readMapOfLists(StreamInput::readString, SegmentReplicationState::new);
+        replicationStats = in.readMapOfLists(StreamInput::readString, SegmentReplicationPerGroupStats::new);
     }
 
     /**
      * Constructs segment replication stats information for a collection of indices and associated shards. Keeps track of how many total shards
      * were seen, and out of those how many were successfully processed and how many failed.
      *
-     * @param totalShards       Total count of shards seen
-     * @param successfulShards  Count of shards successfully processed
-     * @param failedShards      Count of shards which failed to process
-     * @param shardSegmentReplicationStates    Map of indices to shard replication information
-     * @param shardFailures     List of failures processing shards
+     * @param totalShards             Total count of shards seen
+     * @param successfulShards        Count of shards successfully processed
+     * @param failedShards            Count of shards which failed to process
+     * @param replicationStats Map of indices to a list of {@link SegmentReplicationPerGroupStats}
+     * @param shardFailures           List of failures processing shards
      */
     public SegmentReplicationStatsResponse(
         int totalShards,
         int successfulShards,
         int failedShards,
-        Map<String, List<SegmentReplicationState>> shardSegmentReplicationStates,
+        Map<String, List<SegmentReplicationPerGroupStats>> replicationStats,
         List<DefaultShardOperationFailedException> shardFailures
     ) {
         super(totalShards, successfulShards, failedShards, shardFailures);
-        this.shardSegmentReplicationStates = shardSegmentReplicationStates;
+        this.replicationStats = replicationStats;
     }
 
-    public boolean hasSegmentReplicationStats() {
-        return shardSegmentReplicationStates.size() > 0;
-    }
-
-    public Map<String, List<SegmentReplicationState>> shardSegmentReplicationStates() {
-        return shardSegmentReplicationStates;
+    public Map<String, List<SegmentReplicationPerGroupStats>> getReplicationStats() {
+        return replicationStats;
     }
 
     @Override
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startObject();
-        if (hasSegmentReplicationStats()) {
-            for (String index : shardSegmentReplicationStates.keySet()) {
-                List<SegmentReplicationState> segmentReplicationStates = shardSegmentReplicationStates.get(index);
+        if (replicationStats.size() > 0) {
+            for (String index : replicationStats.keySet()) {
+                List<SegmentReplicationPerGroupStats> segmentReplicationStates = replicationStats.get(index);
                 if (segmentReplicationStates == null || segmentReplicationStates.size() == 0) {
                     continue;
                 }
                 builder.startObject(index);
-                builder.startArray("shards");
-                for (SegmentReplicationState segmentReplicationState : segmentReplicationStates) {
+                builder.startArray("primary_stats");
+                for (SegmentReplicationPerGroupStats segmentReplicationState : segmentReplicationStates) {
                     builder.startObject();
                     segmentReplicationState.toXContent(builder, params);
                     builder.endObject();
@@ -90,7 +86,7 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
     @Override
     public void writeTo(StreamOutput out) throws IOException {
         super.writeTo(out);
-        out.writeMapOfLists(shardSegmentReplicationStates, StreamOutput::writeString, (o, v) -> v.writeTo(o));
+        out.writeMapOfLists(replicationStats, StreamOutput::writeString, (o, v) -> v.writeTo(o));
     }
 
     @Override
diff --git a/server/src/main/java/org/opensearch/action/admin/indices/replication/TransportSegmentReplicationStatsAction.java b/server/src/main/java/org/opensearch/action/admin/indices/replication/TransportSegmentReplicationStatsAction.java
index b216824f420cc..f8d5156ff1192 100644
--- a/server/src/main/java/org/opensearch/action/admin/indices/replication/TransportSegmentReplicationStatsAction.java
+++ b/server/src/main/java/org/opensearch/action/admin/indices/replication/TransportSegmentReplicationStatsAction.java
@@ -8,7 +8,6 @@
 
 package org.opensearch.action.admin.indices.replication;
 
-import org.opensearch.OpenSearchStatusException;
 import org.opensearch.action.support.ActionFilters;
 import org.opensearch.action.support.DefaultShardOperationFailedException;
 import org.opensearch.action.support.broadcast.node.TransportBroadcastByNodeAction;
@@ -22,22 +21,24 @@
 import org.opensearch.common.inject.Inject;
 import org.opensearch.common.io.stream.StreamInput;
 import org.opensearch.index.IndexService;
+import org.opensearch.index.SegmentReplicationPerGroupStats;
+import org.opensearch.index.SegmentReplicationPressureService;
+import org.opensearch.index.SegmentReplicationShardStats;
 import org.opensearch.index.shard.IndexShard;
 import org.opensearch.index.shard.ShardId;
 import org.opensearch.indices.IndicesService;
 import org.opensearch.indices.replication.SegmentReplicationState;
 import org.opensearch.indices.replication.SegmentReplicationTargetService;
-import org.opensearch.rest.RestStatus;
 import org.opensearch.threadpool.ThreadPool;
 import org.opensearch.transport.TransportService;
 
 import java.io.IOException;
-import java.util.HashSet;
-import java.util.Set;
+import java.util.Arrays;
 import java.util.List;
 import java.util.ArrayList;
 import java.util.Map;
 import java.util.HashMap;
+import java.util.stream.Collectors;
 
 /**
  * Transport action for shard segment replication operation. This transport action does not actually
@@ -48,11 +49,11 @@
 public class TransportSegmentReplicationStatsAction extends TransportBroadcastByNodeAction<
     SegmentReplicationStatsRequest,
     SegmentReplicationStatsResponse,
-    SegmentReplicationState> {
+    SegmentReplicationShardStatsResponse> {
 
     private final SegmentReplicationTargetService targetService;
     private final IndicesService indicesService;
-    private String singleIndexWithSegmentReplicationDisabled = null;
+    private final SegmentReplicationPressureService pressureService;
 
     @Inject
     public TransportSegmentReplicationStatsAction(
@@ -61,7 +62,8 @@ public TransportSegmentReplicationStatsAction(
         IndicesService indicesService,
         SegmentReplicationTargetService targetService,
         ActionFilters actionFilters,
-        IndexNameExpressionResolver indexNameExpressionResolver
+        IndexNameExpressionResolver indexNameExpressionResolver,
+        SegmentReplicationPressureService pressureService
     ) {
         super(
             SegmentReplicationStatsAction.NAME,
@@ -74,11 +76,12 @@ public TransportSegmentReplicationStatsAction(
         );
         this.indicesService = indicesService;
         this.targetService = targetService;
+        this.pressureService = pressureService;
     }
 
     @Override
-    protected SegmentReplicationState readShardResult(StreamInput in) throws IOException {
-        return new SegmentReplicationState(in);
+    protected SegmentReplicationShardStatsResponse readShardResult(StreamInput in) throws IOException {
+        return new SegmentReplicationShardStatsResponse(in);
     }
 
     @Override
@@ -87,41 +90,51 @@ protected SegmentReplicationStatsResponse newResponse(
         int totalShards,
         int successfulShards,
         int failedShards,
-        List<SegmentReplicationState> responses,
+        List<SegmentReplicationShardStatsResponse> responses,
         List<DefaultShardOperationFailedException> shardFailures,
         ClusterState clusterState
     ) {
-        // throw exception if API call is made on single index with segment replication disabled.
-        if (singleIndexWithSegmentReplicationDisabled != null) {
-            String index = singleIndexWithSegmentReplicationDisabled;
-            singleIndexWithSegmentReplicationDisabled = null;
-            throw new OpenSearchStatusException("Segment Replication is not enabled on Index: " + index, RestStatus.BAD_REQUEST);
-        }
         String[] shards = request.shards();
-        Set<String> set = new HashSet<>();
-        if (shards.length > 0) {
-            for (String shard : shards) {
-                set.add(shard);
+        final List<Integer> shardsToFetch = Arrays.stream(shards).map(Integer::valueOf).collect(Collectors.toList());
+
+        // organize replica responses by allocationId.
+        final Map<String, SegmentReplicationState> replicaStats = new HashMap<>();
+        // map of index name to list of replication group stats.
+        final Map<String, List<SegmentReplicationPerGroupStats>> primaryStats = new HashMap<>();
+        for (SegmentReplicationShardStatsResponse response : responses) {
+            if (response != null) {
+                if (response.getReplicaStats() != null) {
+                    final ShardRouting shardRouting = response.getReplicaStats().getShardRouting();
+                    if (shardsToFetch.isEmpty() || shardsToFetch.contains(shardRouting.shardId().getId())) {
+                        replicaStats.putIfAbsent(shardRouting.allocationId().getId(), response.getReplicaStats());
+                    }
+                }
+                if (response.getPrimaryStats() != null) {
+                    final ShardId shardId = response.getPrimaryStats().getShardId();
+                    if (shardsToFetch.isEmpty() || shardsToFetch.contains(shardId.getId())) {
+                        primaryStats.compute(shardId.getIndexName(), (k, v) -> {
+                            if (v == null) {
+                                final ArrayList<SegmentReplicationPerGroupStats> list = new ArrayList<>();
+                                list.add(response.getPrimaryStats());
+                                return list;
+                            } else {
+                                v.add(response.getPrimaryStats());
+                                return v;
+                            }
+                        });
+                    }
+                }
             }
         }
-        Map<String, List<SegmentReplicationState>> shardResponses = new HashMap<>();
-        for (SegmentReplicationState segmentReplicationState : responses) {
-            if (segmentReplicationState == null) {
-                continue;
-            }
-
-            // Limit responses to only specific shard id's passed in query paramter shards.
-            int shardId = segmentReplicationState.getShardRouting().shardId().id();
-            if (shards.length > 0 && set.contains(Integer.toString(shardId)) == false) {
-                continue;
-            }
-            String indexName = segmentReplicationState.getShardRouting().getIndexName();
-            if (!shardResponses.containsKey(indexName)) {
-                shardResponses.put(indexName, new ArrayList<>());
+        // combine the replica stats to the shard stat entry in each group.
+        for (Map.Entry<String, List<SegmentReplicationPerGroupStats>> entry : primaryStats.entrySet()) {
+            for (SegmentReplicationPerGroupStats group : entry.getValue()) {
+                for (SegmentReplicationShardStats replicaStat : group.getReplicaStats()) {
+                    replicaStat.setCurrentReplicationState(replicaStats.getOrDefault(replicaStat.getAllocationId(), null));
+                }
             }
-            shardResponses.get(indexName).add(segmentReplicationState);
         }
-        return new SegmentReplicationStatsResponse(totalShards, successfulShards, failedShards, shardResponses, shardFailures);
+        return new SegmentReplicationStatsResponse(totalShards, successfulShards, failedShards, primaryStats, shardFailures);
     }
 
     @Override
@@ -130,30 +143,24 @@ protected SegmentReplicationStatsRequest readRequestFrom(StreamInput in) throws
     }
 
     @Override
-    protected SegmentReplicationState shardOperation(SegmentReplicationStatsRequest request, ShardRouting shardRouting) {
+    protected SegmentReplicationShardStatsResponse shardOperation(SegmentReplicationStatsRequest request, ShardRouting shardRouting) {
         IndexService indexService = indicesService.indexServiceSafe(shardRouting.shardId().getIndex());
         IndexShard indexShard = indexService.getShard(shardRouting.shardId().id());
         ShardId shardId = shardRouting.shardId();
 
-        // check if API call is made on single index with segment replication disabled.
-        if (request.indices().length == 1 && indexShard.indexSettings().isSegRepEnabled() == false) {
-            singleIndexWithSegmentReplicationDisabled = shardRouting.getIndexName();
+        if (indexShard.indexSettings().isSegRepEnabled() == false) {
             return null;
         }
-        if (indexShard.indexSettings().isSegRepEnabled() == false || shardRouting.primary()) {
-            return null;
+
+        if (shardRouting.primary()) {
+            return new SegmentReplicationShardStatsResponse(pressureService.getStatsForShard(indexShard));
         }
 
         // return information about only on-going segment replication events.
         if (request.activeOnly()) {
-            return targetService.getOngoingEventSegmentReplicationState(shardId);
-        }
-
-        // return information about only latest completed segment replication events.
-        if (request.completedOnly()) {
-            return targetService.getlatestCompletedEventSegmentReplicationState(shardId);
+            return new SegmentReplicationShardStatsResponse(targetService.getOngoingEventSegmentReplicationState(shardId));
         }
-        return targetService.getSegmentReplicationState(shardId);
+        return new SegmentReplicationShardStatsResponse(targetService.getSegmentReplicationState(shardId));
     }
 
     @Override
diff --git a/server/src/main/java/org/opensearch/action/admin/indices/rollover/MetadataRolloverService.java b/server/src/main/java/org/opensearch/action/admin/indices/rollover/MetadataRolloverService.java
index c3862bb115b21..65b18845b919a 100644
--- a/server/src/main/java/org/opensearch/action/admin/indices/rollover/MetadataRolloverService.java
+++ b/server/src/main/java/org/opensearch/action/admin/indices/rollover/MetadataRolloverService.java
@@ -74,7 +74,7 @@
  */
 public class MetadataRolloverService {
     private static final Pattern INDEX_NAME_PATTERN = Pattern.compile("^.*-\\d+$");
-    private static final List<IndexAbstraction.Type> VALID_ROLLOVER_TARGETS = org.opensearch.common.collect.List.of(ALIAS, DATA_STREAM);
+    private static final List<IndexAbstraction.Type> VALID_ROLLOVER_TARGETS = List.of(ALIAS, DATA_STREAM);
 
     private final ThreadPool threadPool;
     private final MetadataCreateIndexService createIndexService;
diff --git a/server/src/main/java/org/opensearch/action/bulk/TransportShardBulkAction.java b/server/src/main/java/org/opensearch/action/bulk/TransportShardBulkAction.java
index 0657fab55b220..2552d43688f00 100644
--- a/server/src/main/java/org/opensearch/action/bulk/TransportShardBulkAction.java
+++ b/server/src/main/java/org/opensearch/action/bulk/TransportShardBulkAction.java
@@ -81,6 +81,7 @@
 import org.opensearch.common.xcontent.XContentHelper;
 import org.opensearch.common.xcontent.XContentType;
 import org.opensearch.index.IndexingPressureService;
+import org.opensearch.index.SegmentReplicationPressureService;
 import org.opensearch.index.engine.Engine;
 import org.opensearch.index.engine.VersionConflictEngineException;
 import org.opensearch.index.get.GetResult;
@@ -133,6 +134,7 @@ public class TransportShardBulkAction extends TransportWriteAction<BulkShardRequ
 
     private final UpdateHelper updateHelper;
     private final MappingUpdatedAction mappingUpdatedAction;
+    private final SegmentReplicationPressureService segmentReplicationPressureService;
 
     /**
      * This action is used for performing primary term validation. With remote translog enabled, the translogs would
@@ -155,6 +157,7 @@ public TransportShardBulkAction(
         UpdateHelper updateHelper,
         ActionFilters actionFilters,
         IndexingPressureService indexingPressureService,
+        SegmentReplicationPressureService segmentReplicationPressureService,
         SystemIndices systemIndices
     ) {
         super(
@@ -175,6 +178,7 @@ public TransportShardBulkAction(
         );
         this.updateHelper = updateHelper;
         this.mappingUpdatedAction = mappingUpdatedAction;
+        this.segmentReplicationPressureService = segmentReplicationPressureService;
 
         this.transportPrimaryTermValidationAction = ACTION_NAME + "[validate_primary_term]";
 
@@ -522,6 +526,14 @@ private void finishRequest() {
         }.run();
     }
 
+    @Override
+    protected Releasable checkPrimaryLimits(BulkShardRequest request, boolean rerouteWasLocal, boolean localRerouteInitiatedByNodeClient) {
+        if (force(request) == false && segmentReplicationPressureService.isSegmentReplicationBackpressureEnabled()) {
+            segmentReplicationPressureService.isSegrepLimitBreached(request.shardId());
+        }
+        return super.checkPrimaryLimits(request, rerouteWasLocal, localRerouteInitiatedByNodeClient);
+    }
+
     /**
      * Executes bulk item requests and handles request execution exceptions.
      * @return {@code true} if request completed on this thread and the listener was invoked, {@code false} if the request triggered
diff --git a/server/src/main/java/org/opensearch/action/fieldcaps/TransportFieldCapabilitiesIndexAction.java b/server/src/main/java/org/opensearch/action/fieldcaps/TransportFieldCapabilitiesIndexAction.java
index e33e03b90ddfc..4fffce147c6dc 100644
--- a/server/src/main/java/org/opensearch/action/fieldcaps/TransportFieldCapabilitiesIndexAction.java
+++ b/server/src/main/java/org/opensearch/action/fieldcaps/TransportFieldCapabilitiesIndexAction.java
@@ -267,7 +267,8 @@ private ShardRouting nextRoutingOrNull(Exception failure) {
             if (shardsIt.size() == 0 || shardIndex >= shardsIt.size()) {
                 return null;
             }
-            ShardRouting next = FailAwareWeightedRouting.getInstance().findNext(shardsIt.get(shardIndex), clusterService.state(), failure);
+            ShardRouting next = FailAwareWeightedRouting.getInstance()
+                .findNext(shardsIt.get(shardIndex), clusterService.state(), failure, this::moveToNextShard);
 
             if (next != null) {
                 return next;
diff --git a/server/src/main/java/org/opensearch/action/ingest/SimulateExecutionService.java b/server/src/main/java/org/opensearch/action/ingest/SimulateExecutionService.java
index ae66dafc954f9..82db29c950161 100644
--- a/server/src/main/java/org/opensearch/action/ingest/SimulateExecutionService.java
+++ b/server/src/main/java/org/opensearch/action/ingest/SimulateExecutionService.java
@@ -76,10 +76,9 @@ void executeDocument(
                 pipeline.getVersion(),
                 verbosePipelineProcessor
             );
-            ingestDocument.executePipeline(
-                verbosePipeline,
-                (result, e) -> { handler.accept(new SimulateDocumentVerboseResult(processorResultList), e); }
-            );
+            ingestDocument.executePipeline(verbosePipeline, (result, e) -> {
+                handler.accept(new SimulateDocumentVerboseResult(processorResultList), e);
+            });
         } else {
             ingestDocument.executePipeline(pipeline, (result, e) -> {
                 if (e == null) {
diff --git a/server/src/main/java/org/opensearch/action/search/AbstractSearchAsyncAction.java b/server/src/main/java/org/opensearch/action/search/AbstractSearchAsyncAction.java
index 6b6678361b2b5..9a94737c84385 100644
--- a/server/src/main/java/org/opensearch/action/search/AbstractSearchAsyncAction.java
+++ b/server/src/main/java/org/opensearch/action/search/AbstractSearchAsyncAction.java
@@ -450,7 +450,8 @@ private void onShardFailure(final int shardIndex, @Nullable SearchShardTarget sh
         // we always add the shard failure for a specific shard instance
         // we do make sure to clean it on a successful response from a shard
         onShardFailure(shardIndex, shard, e);
-        SearchShardTarget nextShard = FailAwareWeightedRouting.getInstance().findNext(shardIt, clusterState, e);
+        SearchShardTarget nextShard = FailAwareWeightedRouting.getInstance()
+            .findNext(shardIt, clusterState, e, () -> totalOps.incrementAndGet());
 
         final boolean lastShard = nextShard == null;
         logger.debug(
diff --git a/server/src/main/java/org/opensearch/action/search/DeletePitResponse.java b/server/src/main/java/org/opensearch/action/search/DeletePitResponse.java
index cdbeb3dc2b749..5ea959bc9acf9 100644
--- a/server/src/main/java/org/opensearch/action/search/DeletePitResponse.java
+++ b/server/src/main/java/org/opensearch/action/search/DeletePitResponse.java
@@ -24,7 +24,6 @@
 import java.util.List;
 
 import static org.opensearch.common.xcontent.ConstructingObjectParser.constructorArg;
-import static org.opensearch.rest.RestStatus.NOT_FOUND;
 import static org.opensearch.rest.RestStatus.OK;
 
 /**
@@ -57,7 +56,6 @@ public List<DeletePitInfo> getDeletePitResults() {
      */
     @Override
     public RestStatus status() {
-        if (deletePitResults.isEmpty()) return NOT_FOUND;
         return OK;
     }
 
diff --git a/server/src/main/java/org/opensearch/action/search/SearchTransportService.java b/server/src/main/java/org/opensearch/action/search/SearchTransportService.java
index 241b3de72a258..94a6262874ac2 100644
--- a/server/src/main/java/org/opensearch/action/search/SearchTransportService.java
+++ b/server/src/main/java/org/opensearch/action/search/SearchTransportService.java
@@ -514,7 +514,9 @@ public static void registerRequestHandler(TransportService transportService, Sea
             FREE_PIT_CONTEXT_ACTION_NAME,
             ThreadPool.Names.SAME,
             PitFreeContextsRequest::new,
-            (request, channel, task) -> { channel.sendResponse(searchService.freeReaderContextsIfFound(request.getContextIds())); }
+            (request, channel, task) -> {
+                channel.sendResponse(searchService.freeReaderContextsIfFound(request.getContextIds()));
+            }
         );
         TransportActionProxy.registerProxyAction(transportService, FREE_PIT_CONTEXT_ACTION_NAME, DeletePitResponse::new);
 
diff --git a/server/src/main/java/org/opensearch/action/support/broadcast/TransportBroadcastAction.java b/server/src/main/java/org/opensearch/action/support/broadcast/TransportBroadcastAction.java
index 10645c744b2f3..5abf97b7ef979 100644
--- a/server/src/main/java/org/opensearch/action/support/broadcast/TransportBroadcastAction.java
+++ b/server/src/main/java/org/opensearch/action/support/broadcast/TransportBroadcastAction.java
@@ -251,7 +251,8 @@ void onOperation(@Nullable ShardRouting shard, final ShardIterator shardIt, int
             // we set the shard failure always, even if its the first in the replication group, and the next one
             // will work (it will just override it...)
             setFailure(shardIt, shardIndex, e);
-            ShardRouting nextShard = FailAwareWeightedRouting.getInstance().findNext(shardIt, clusterService.state(), e);
+            ShardRouting nextShard = FailAwareWeightedRouting.getInstance()
+                .findNext(shardIt, clusterService.state(), e, () -> counterOps.incrementAndGet());
 
             if (nextShard != null) {
                 if (e != null) {
diff --git a/server/src/main/java/org/opensearch/action/support/single/shard/TransportSingleShardAction.java b/server/src/main/java/org/opensearch/action/support/single/shard/TransportSingleShardAction.java
index d8c4913e595a4..927d3946a3643 100644
--- a/server/src/main/java/org/opensearch/action/support/single/shard/TransportSingleShardAction.java
+++ b/server/src/main/java/org/opensearch/action/support/single/shard/TransportSingleShardAction.java
@@ -245,7 +245,8 @@ private void perform(@Nullable final Exception currentFailure) {
                 lastFailure = currentFailure;
                 this.lastFailure = currentFailure;
             }
-            ShardRouting shardRouting = FailAwareWeightedRouting.getInstance().findNext(shardIt, clusterService.state(), currentFailure);
+            ShardRouting shardRouting = FailAwareWeightedRouting.getInstance()
+                .findNext(shardIt, clusterService.state(), currentFailure, () -> {});
 
             if (shardRouting == null) {
                 Exception failure = lastFailure;
diff --git a/server/src/main/java/org/opensearch/bootstrap/Security.java b/server/src/main/java/org/opensearch/bootstrap/Security.java
index 8e913e05390c2..5b6ade0f3b461 100644
--- a/server/src/main/java/org/opensearch/bootstrap/Security.java
+++ b/server/src/main/java/org/opensearch/bootstrap/Security.java
@@ -36,7 +36,6 @@
 import org.opensearch.common.SuppressForbidden;
 import org.opensearch.common.io.PathUtils;
 import org.opensearch.common.settings.Settings;
-import org.opensearch.common.util.FeatureFlags;
 import org.opensearch.env.Environment;
 import org.opensearch.http.HttpTransportSettings;
 import org.opensearch.plugins.PluginInfo;
@@ -317,9 +316,7 @@ static void addFilePermissions(Permissions policy, Environment environment) thro
         addDirectoryPath(policy, Environment.PATH_HOME_SETTING.getKey(), environment.libFile(), "read,readlink", false);
         addDirectoryPath(policy, Environment.PATH_HOME_SETTING.getKey(), environment.modulesFile(), "read,readlink", false);
         addDirectoryPath(policy, Environment.PATH_HOME_SETTING.getKey(), environment.pluginsFile(), "read,readlink", false);
-        if (FeatureFlags.isEnabled(FeatureFlags.EXTENSIONS)) {
-            addDirectoryPath(policy, Environment.PATH_HOME_SETTING.getKey(), environment.extensionDir(), "read,readlink", false);
-        }
+        addDirectoryPath(policy, Environment.PATH_HOME_SETTING.getKey(), environment.extensionDir(), "read,readlink", false);
         addDirectoryPath(policy, "path.conf'", environment.configFile(), "read,readlink", false);
         // read-write dirs
         addDirectoryPath(policy, "java.io.tmpdir", environment.tmpFile(), "read,readlink,write,delete", false);
diff --git a/server/src/main/java/org/opensearch/cluster/ClusterInfo.java b/server/src/main/java/org/opensearch/cluster/ClusterInfo.java
index 6c7f4ba487568..17105c5b68b10 100644
--- a/server/src/main/java/org/opensearch/cluster/ClusterInfo.java
+++ b/server/src/main/java/org/opensearch/cluster/ClusterInfo.java
@@ -103,7 +103,7 @@ public ClusterInfo(StreamInput in) throws IOException {
         if (in.getVersion().onOrAfter(StoreStats.RESERVED_BYTES_VERSION)) {
             reservedSpaceMap = in.readMap(NodeAndPath::new, ReservedSpace::new);
         } else {
-            reservedSpaceMap = org.opensearch.common.collect.Map.of();
+            reservedSpaceMap = Map.of();
         }
 
         ImmutableOpenMap.Builder<String, DiskUsage> leastBuilder = ImmutableOpenMap.builder();
diff --git a/server/src/main/java/org/opensearch/cluster/metadata/ComposableIndexTemplate.java b/server/src/main/java/org/opensearch/cluster/metadata/ComposableIndexTemplate.java
index 33200b46a5e98..630684e267093 100644
--- a/server/src/main/java/org/opensearch/cluster/metadata/ComposableIndexTemplate.java
+++ b/server/src/main/java/org/opensearch/cluster/metadata/ComposableIndexTemplate.java
@@ -59,7 +59,6 @@
 
 import static java.util.Collections.singletonMap;
 import static java.util.Collections.unmodifiableMap;
-import static org.opensearch.common.collect.Map.of;
 
 /**
  * An index template is comprised of a set of index patterns, an optional template, and a list of
@@ -337,7 +336,10 @@ public TimestampField getTimestampField() {
         public Map<String, Object> getDataStreamMappingSnippet() {
             return singletonMap(
                 MapperService.SINGLE_MAPPING_NAME,
-                singletonMap("_data_stream_timestamp", unmodifiableMap(of("enabled", true, "timestamp_field", getTimestampField().toMap())))
+                singletonMap(
+                    "_data_stream_timestamp",
+                    unmodifiableMap(Map.of("enabled", true, "timestamp_field", getTimestampField().toMap()))
+                )
             );
         }
 
diff --git a/server/src/main/java/org/opensearch/cluster/metadata/IndexAbstraction.java b/server/src/main/java/org/opensearch/cluster/metadata/IndexAbstraction.java
index f9328d5b61183..11ead3e29c346 100644
--- a/server/src/main/java/org/opensearch/cluster/metadata/IndexAbstraction.java
+++ b/server/src/main/java/org/opensearch/cluster/metadata/IndexAbstraction.java
@@ -46,7 +46,6 @@
 
 import static org.opensearch.cluster.metadata.DataStream.getDefaultBackingIndexName;
 import static org.opensearch.cluster.metadata.IndexMetadata.INDEX_HIDDEN_SETTING;
-import static org.opensearch.common.collect.List.copyOf;
 
 /**
  * An index abstraction is a reference to one or more concrete indices.
@@ -346,7 +345,7 @@ class DataStream implements IndexAbstraction {
 
         public DataStream(org.opensearch.cluster.metadata.DataStream dataStream, List<IndexMetadata> dataStreamIndices) {
             this.dataStream = dataStream;
-            this.dataStreamIndices = copyOf(dataStreamIndices);
+            this.dataStreamIndices = List.copyOf(dataStreamIndices);
             this.writeIndex = dataStreamIndices.get(dataStreamIndices.size() - 1);
             assert writeIndex.getIndex().getName().equals(getDefaultBackingIndexName(dataStream.getName(), dataStream.getGeneration()));
         }
diff --git a/server/src/main/java/org/opensearch/cluster/metadata/IndexNameExpressionResolver.java b/server/src/main/java/org/opensearch/cluster/metadata/IndexNameExpressionResolver.java
index 3d1609e0eb9c0..1fbb042edca76 100644
--- a/server/src/main/java/org/opensearch/cluster/metadata/IndexNameExpressionResolver.java
+++ b/server/src/main/java/org/opensearch/cluster/metadata/IndexNameExpressionResolver.java
@@ -90,10 +90,7 @@ public class IndexNameExpressionResolver {
 
     private final DateMathExpressionResolver dateMathExpressionResolver = new DateMathExpressionResolver();
     private final WildcardExpressionResolver wildcardExpressionResolver = new WildcardExpressionResolver();
-    private final List<ExpressionResolver> expressionResolvers = org.opensearch.common.collect.List.of(
-        dateMathExpressionResolver,
-        wildcardExpressionResolver
-    );
+    private final List<ExpressionResolver> expressionResolvers = List.of(dateMathExpressionResolver, wildcardExpressionResolver);
 
     private final ThreadContext threadContext;
 
@@ -177,7 +174,7 @@ public List<String> dataStreamNames(ClusterState state, IndicesOptions options,
         }
 
         List<String> dataStreams = wildcardExpressionResolver.resolve(context, Arrays.asList(indexExpressions));
-        return ((dataStreams == null) ? org.opensearch.common.collect.List.<String>of() : dataStreams).stream()
+        return ((dataStreams == null) ? List.<String>of() : dataStreams).stream()
             .map(x -> state.metadata().getIndicesLookup().get(x))
             .filter(Objects::nonNull)
             .filter(ia -> ia.getType() == IndexAbstraction.Type.DATA_STREAM)
diff --git a/server/src/main/java/org/opensearch/cluster/metadata/MetadataCreateDataStreamService.java b/server/src/main/java/org/opensearch/cluster/metadata/MetadataCreateDataStreamService.java
index 7be5ea7e2c34a..b34e37aea8b7d 100644
--- a/server/src/main/java/org/opensearch/cluster/metadata/MetadataCreateDataStreamService.java
+++ b/server/src/main/java/org/opensearch/cluster/metadata/MetadataCreateDataStreamService.java
@@ -100,7 +100,9 @@ public void createDataStream(CreateDataStreamClusterStateUpdateRequest request,
                     new String[] { firstBackingIndexName },
                     ActiveShardCount.DEFAULT,
                     request.masterNodeTimeout(),
-                    shardsAcked -> { finalListener.onResponse(new AcknowledgedResponse(true)); },
+                    shardsAcked -> {
+                        finalListener.onResponse(new AcknowledgedResponse(true));
+                    },
                     finalListener::onFailure
                 );
             } else {
diff --git a/server/src/main/java/org/opensearch/cluster/metadata/MetadataCreateIndexService.java b/server/src/main/java/org/opensearch/cluster/metadata/MetadataCreateIndexService.java
index d904459af38b8..9c0825158da09 100644
--- a/server/src/main/java/org/opensearch/cluster/metadata/MetadataCreateIndexService.java
+++ b/server/src/main/java/org/opensearch/cluster/metadata/MetadataCreateIndexService.java
@@ -731,7 +731,7 @@ private ClusterState applyCreateIndexRequestWithExistingMetadata(
                 // shard id and the current timestamp
                 indexService.newQueryShardContext(0, null, () -> 0L, null)
             ),
-            org.opensearch.common.collect.List.of(),
+            List.of(),
             metadataTransformer
         );
     }
diff --git a/server/src/main/java/org/opensearch/cluster/routing/FailAwareWeightedRouting.java b/server/src/main/java/org/opensearch/cluster/routing/FailAwareWeightedRouting.java
index 1e4c8a24863cd..dbef876c9a258 100644
--- a/server/src/main/java/org/opensearch/cluster/routing/FailAwareWeightedRouting.java
+++ b/server/src/main/java/org/opensearch/cluster/routing/FailAwareWeightedRouting.java
@@ -60,9 +60,17 @@ private boolean isInternalFailure(Exception exception) {
      * routing weight set to zero
      *
      * @param shardIt Shard Iterator containing order in which shard copies for a shard need to be requested
+     * @param clusterState The current cluster state
+     * @param exception The underlying search exception
+     * @param onShardSkipped The runnable to execute once a shard is skipped
      * @return the next shard copy
      */
-    public SearchShardTarget findNext(final SearchShardIterator shardIt, ClusterState clusterState, Exception exception) {
+    public SearchShardTarget findNext(
+        final SearchShardIterator shardIt,
+        ClusterState clusterState,
+        Exception exception,
+        Runnable onShardSkipped
+    ) {
         SearchShardTarget next = shardIt.nextOrNull();
         while (next != null && WeightedRoutingUtils.isWeighedAway(next.getNodeId(), clusterState)) {
             SearchShardTarget nextShard = next;
@@ -72,6 +80,7 @@ public SearchShardTarget findNext(final SearchShardIterator shardIt, ClusterStat
                 break;
             }
             next = shardIt.nextOrNull();
+            onShardSkipped.run();
         }
         return next;
     }
@@ -82,9 +91,12 @@ public SearchShardTarget findNext(final SearchShardIterator shardIt, ClusterStat
      * routing weight set to zero
      *
      * @param shardsIt Shard Iterator containing order in which shard copies for a shard need to be requested
+     * @param clusterState The current cluster state
+     * @param exception The underlying search exception
+     * @param onShardSkipped The runnable to execute once a shard is skipped
      * @return the next shard copy
      */
-    public ShardRouting findNext(final ShardsIterator shardsIt, ClusterState clusterState, Exception exception) {
+    public ShardRouting findNext(final ShardsIterator shardsIt, ClusterState clusterState, Exception exception, Runnable onShardSkipped) {
         ShardRouting next = shardsIt.nextOrNull();
 
         while (next != null && WeightedRoutingUtils.isWeighedAway(next.currentNodeId(), clusterState)) {
@@ -95,6 +107,7 @@ public ShardRouting findNext(final ShardsIterator shardsIt, ClusterState cluster
                 break;
             }
             next = shardsIt.nextOrNull();
+            onShardSkipped.run();
         }
         return next;
     }
diff --git a/server/src/main/java/org/opensearch/cluster/routing/allocation/AllocationConstraints.java b/server/src/main/java/org/opensearch/cluster/routing/allocation/AllocationConstraints.java
index 3d9847ca35931..e8ab0738c18da 100644
--- a/server/src/main/java/org/opensearch/cluster/routing/allocation/AllocationConstraints.java
+++ b/server/src/main/java/org/opensearch/cluster/routing/allocation/AllocationConstraints.java
@@ -8,80 +8,39 @@
 import org.opensearch.cluster.routing.allocation.allocator.BalancedShardsAllocator;
 import org.opensearch.cluster.routing.allocation.allocator.ShardsBalancer;
 
-import java.util.ArrayList;
-import java.util.List;
-import java.util.function.Predicate;
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.CLUSTER_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID;
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.INDEX_SHARD_PER_NODE_BREACH_CONSTRAINT_ID;
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID;
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.isIndexShardsPerNodeBreached;
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.isPerIndexPrimaryShardsPerNodeBreached;
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.isPrimaryShardsPerNodeBreached;
 
 /**
- * Allocation constraints specify conditions which, if breached, reduce the
- * priority of a node for receiving shard allocations.
+ * Allocation constraints specify conditions which, if breached, reduce the priority of a node for receiving unassigned
+ * shard allocations. Weight calculation in other scenarios like shard movement and re-balancing remain unaffected by
+ * this constraint.
  *
  * @opensearch.internal
  */
 public class AllocationConstraints {
-    public final long CONSTRAINT_WEIGHT = 1000000L;
-    private List<Predicate<ConstraintParams>> constraintPredicates;
+    private Map<String, Constraint> constraints;
 
     public AllocationConstraints() {
-        this.constraintPredicates = new ArrayList<>(1);
-        this.constraintPredicates.add(isIndexShardsPerNodeBreached());
+        this.constraints = new HashMap<>();
+        this.constraints.putIfAbsent(INDEX_SHARD_PER_NODE_BREACH_CONSTRAINT_ID, new Constraint(isIndexShardsPerNodeBreached()));
+        this.constraints.putIfAbsent(INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, new Constraint(isPerIndexPrimaryShardsPerNodeBreached()));
+        this.constraints.putIfAbsent(CLUSTER_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, new Constraint(isPrimaryShardsPerNodeBreached()));
     }
 
-    class ConstraintParams {
-        private ShardsBalancer balancer;
-        private BalancedShardsAllocator.ModelNode node;
-        private String index;
-
-        ConstraintParams(ShardsBalancer balancer, BalancedShardsAllocator.ModelNode node, String index) {
-            this.balancer = balancer;
-            this.node = node;
-            this.index = index;
-        }
+    public void updateAllocationConstraint(String constraint, boolean enable) {
+        this.constraints.get(constraint).setEnable(enable);
     }
 
-    /**
-     * Evaluates configured allocation constraint predicates for given node - index
-     * combination; and returns a weight value based on the number of breached
-     * constraints.
-     *
-     * Constraint weight should be added to the weight calculated via weight
-     * function, to reduce priority of allocating on nodes with breached
-     * constraints.
-     *
-     * This weight function is used only in case of unassigned shards to avoid overloading a newly added node.
-     * Weight calculation in other scenarios like shard movement and re-balancing remain unaffected by this function.
-     */
     public long weight(ShardsBalancer balancer, BalancedShardsAllocator.ModelNode node, String index) {
-        int constraintsBreached = 0;
-        ConstraintParams params = new ConstraintParams(balancer, node, index);
-        for (Predicate<ConstraintParams> predicate : constraintPredicates) {
-            if (predicate.test(params)) {
-                constraintsBreached++;
-            }
-        }
-        return constraintsBreached * CONSTRAINT_WEIGHT;
+        Constraint.ConstraintParams params = new Constraint.ConstraintParams(balancer, node, index);
+        return params.weight(constraints);
     }
-
-    /**
-     * Constraint to control number of shards of an index allocated on a single
-     * node.
-     *
-     * In current weight function implementation, when a node has significantly
-     * fewer shards than other nodes (e.g. during single new node addition or node
-     * replacement), its weight is much less than other nodes. All shard allocations
-     * at this time tend to land on the new node with skewed weight. This breaks
-     * index level balance in the cluster, by creating all shards of the same index
-     * on one node, often resulting in a hotspot on that node.
-     *
-     * This constraint is breached when balancer attempts to allocate more than
-     * average shards per index per node.
-     */
-    private Predicate<ConstraintParams> isIndexShardsPerNodeBreached() {
-        return (params) -> {
-            int currIndexShardsOnNode = params.node.numShards(params.index);
-            int allowedIndexShardsPerNode = (int) Math.ceil(params.balancer.avgShardsPerNode(params.index));
-            return (currIndexShardsOnNode >= allowedIndexShardsPerNode);
-        };
-    }
-
 }
diff --git a/server/src/main/java/org/opensearch/cluster/routing/allocation/Constraint.java b/server/src/main/java/org/opensearch/cluster/routing/allocation/Constraint.java
new file mode 100644
index 0000000000000..e9c3c0afcbe88
--- /dev/null
+++ b/server/src/main/java/org/opensearch/cluster/routing/allocation/Constraint.java
@@ -0,0 +1,86 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.cluster.routing.allocation;
+
+import org.opensearch.cluster.routing.allocation.allocator.BalancedShardsAllocator;
+import org.opensearch.cluster.routing.allocation.allocator.ShardsBalancer;
+
+import java.util.Map;
+import java.util.function.Predicate;
+
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.CONSTRAINT_WEIGHT;
+
+/**
+ * Defines a constraint useful to de-prioritize certain nodes as target of unassigned shards used in {@link AllocationConstraints} or
+ * re-balancing target used in {@link RebalanceConstraints}
+ *
+ * @opensearch.internal
+ */
+public class Constraint implements Predicate<Constraint.ConstraintParams> {
+
+    private boolean enable;
+    private Predicate<ConstraintParams> predicate;
+
+    public Constraint(Predicate<ConstraintParams> constraintPredicate) {
+        this.predicate = constraintPredicate;
+    }
+
+    @Override
+    public boolean test(ConstraintParams constraintParams) {
+        return this.enable && predicate.test(constraintParams);
+    }
+
+    public void setEnable(boolean enable) {
+        this.enable = enable;
+    }
+
+    static class ConstraintParams {
+        private ShardsBalancer balancer;
+        private BalancedShardsAllocator.ModelNode node;
+        private String index;
+
+        ConstraintParams(ShardsBalancer balancer, BalancedShardsAllocator.ModelNode node, String index) {
+            this.balancer = balancer;
+            this.node = node;
+            this.index = index;
+        }
+
+        public ShardsBalancer getBalancer() {
+            return balancer;
+        }
+
+        public BalancedShardsAllocator.ModelNode getNode() {
+            return node;
+        }
+
+        public String getIndex() {
+            return index;
+        }
+
+        /**
+         * Evaluates configured allocation constraint predicates for given node - index
+         * combination; and returns a weight value based on the number of breached
+         * constraints.
+         * <p>
+         * Constraint weight should be added to the weight calculated via weight
+         * function, to reduce priority of allocating on nodes with breached
+         * constraints.
+         * </p>
+         */
+        public long weight(Map<String, Constraint> constraints) {
+            long totalConstraintWeight = 0;
+            for (Constraint constraint : constraints.values()) {
+                if (constraint.test(this)) {
+                    totalConstraintWeight += CONSTRAINT_WEIGHT;
+                }
+            }
+            return totalConstraintWeight;
+        }
+    }
+}
diff --git a/server/src/main/java/org/opensearch/cluster/routing/allocation/ConstraintTypes.java b/server/src/main/java/org/opensearch/cluster/routing/allocation/ConstraintTypes.java
new file mode 100644
index 0000000000000..f209e993518c1
--- /dev/null
+++ b/server/src/main/java/org/opensearch/cluster/routing/allocation/ConstraintTypes.java
@@ -0,0 +1,84 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.cluster.routing.allocation;
+
+import java.util.function.Predicate;
+
+/**
+ * Defines different constraints definitions
+ *
+ * @opensearch.internal
+ */
+public class ConstraintTypes {
+    public final static long CONSTRAINT_WEIGHT = 1000000L;
+
+    /**
+     * Defines per index constraint which is breached when a node contains more than avg number of primary shards for an index
+     */
+    public final static String INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID = "index.primary.shard.balance.constraint";
+
+    /**
+     * Defines a cluster constraint which is breached when a node contains more than avg primary shards across all indices
+     */
+    public final static String CLUSTER_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID = "cluster.primary.shard.balance.constraint";
+
+    /**
+     * Defines an index constraint which is breached when a node contains more than avg number of shards for an index
+     */
+    public final static String INDEX_SHARD_PER_NODE_BREACH_CONSTRAINT_ID = "index.shard.count.constraint";
+
+    /**
+     * Constraint to control number of shards of an index allocated on a single
+     * node.
+     *
+     * In current weight function implementation, when a node has significantly
+     * fewer shards than other nodes (e.g. during single new node addition or node
+     * replacement), its weight is much less than other nodes. All shard allocations
+     * at this time tend to land on the new node with skewed weight. This breaks
+     * index level balance in the cluster, by creating all shards of the same index
+     * on one node, often resulting in a hotspot on that node.
+     *
+     * This constraint is breached when balancer attempts to allocate more than
+     * average shards per index per node.
+     */
+    public static Predicate<Constraint.ConstraintParams> isIndexShardsPerNodeBreached() {
+        return (params) -> {
+            int currIndexShardsOnNode = params.getNode().numShards(params.getIndex());
+            int allowedIndexShardsPerNode = (int) Math.ceil(params.getBalancer().avgShardsPerNode(params.getIndex()));
+            return (currIndexShardsOnNode >= allowedIndexShardsPerNode);
+        };
+    }
+
+    /**
+     * Defines a predicate which returns true when specific to an index, a node contains more than average number of primary
+     * shards. This constraint is used in weight calculation during allocation and rebalancing. When breached a high weight
+     * {@link ConstraintTypes#CONSTRAINT_WEIGHT} is assigned to node resulting in lesser chances of node being selected
+     * as allocation or rebalancing target
+     */
+    public static Predicate<Constraint.ConstraintParams> isPerIndexPrimaryShardsPerNodeBreached() {
+        return (params) -> {
+            int perIndexPrimaryShardCount = params.getNode().numPrimaryShards(params.getIndex());
+            int perIndexAllowedPrimaryShardCount = (int) Math.ceil(params.getBalancer().avgPrimaryShardsPerNode(params.getIndex()));
+            return perIndexPrimaryShardCount > perIndexAllowedPrimaryShardCount;
+        };
+    }
+
+    /**
+     * Defines a predicate which returns true when a node contains more than average number of primary shards. This
+     * constraint is used in weight calculation during allocation only. When breached a high weight {@link ConstraintTypes#CONSTRAINT_WEIGHT}
+     * is assigned to node resulting in lesser chances of node being selected as allocation target
+     */
+    public static Predicate<Constraint.ConstraintParams> isPrimaryShardsPerNodeBreached() {
+        return (params) -> {
+            int primaryShardCount = params.getNode().numPrimaryShards();
+            int allowedPrimaryShardCount = (int) Math.ceil(params.getBalancer().avgPrimaryShardsPerNode());
+            return primaryShardCount >= allowedPrimaryShardCount;
+        };
+    }
+}
diff --git a/server/src/main/java/org/opensearch/cluster/routing/allocation/DiskThresholdMonitor.java b/server/src/main/java/org/opensearch/cluster/routing/allocation/DiskThresholdMonitor.java
index d93dc8b12d28a..6f63aff2f3a90 100644
--- a/server/src/main/java/org/opensearch/cluster/routing/allocation/DiskThresholdMonitor.java
+++ b/server/src/main/java/org/opensearch/cluster/routing/allocation/DiskThresholdMonitor.java
@@ -403,6 +403,7 @@ public void onNewInfo(ClusterInfo info) {
 
         // If all the nodes are breaching high disk watermark, we apply index create block to avoid red clusters.
         if ((state.getBlocks().hasGlobalBlockWithId(Metadata.CLUSTER_CREATE_INDEX_BLOCK.id()) == false)
+            && nodes.size() > 0
             && nodesOverHighThreshold.size() == nodes.size()) {
             setIndexCreateBlock(listener, true);
         } else if (state.getBlocks().hasGlobalBlockWithId(Metadata.CLUSTER_CREATE_INDEX_BLOCK.id())
diff --git a/server/src/main/java/org/opensearch/cluster/routing/allocation/RebalanceConstraints.java b/server/src/main/java/org/opensearch/cluster/routing/allocation/RebalanceConstraints.java
new file mode 100644
index 0000000000000..a4036ec47ec0e
--- /dev/null
+++ b/server/src/main/java/org/opensearch/cluster/routing/allocation/RebalanceConstraints.java
@@ -0,0 +1,43 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.cluster.routing.allocation;
+
+import org.opensearch.cluster.routing.allocation.allocator.BalancedShardsAllocator;
+import org.opensearch.cluster.routing.allocation.allocator.ShardsBalancer;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID;
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.isPerIndexPrimaryShardsPerNodeBreached;
+
+/**
+ * Constraints applied during rebalancing round; specify conditions which, if breached, reduce the
+ * priority of a node for receiving shard relocations.
+ *
+ * @opensearch.internal
+ */
+public class RebalanceConstraints {
+
+    private Map<String, Constraint> constraints;
+
+    public RebalanceConstraints() {
+        this.constraints = new HashMap<>();
+        this.constraints.putIfAbsent(INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, new Constraint(isPerIndexPrimaryShardsPerNodeBreached()));
+    }
+
+    public void updateRebalanceConstraint(String constraint, boolean enable) {
+        this.constraints.get(constraint).setEnable(enable);
+    }
+
+    public long weight(ShardsBalancer balancer, BalancedShardsAllocator.ModelNode node, String index) {
+        Constraint.ConstraintParams params = new Constraint.ConstraintParams(balancer, node, index);
+        return params.weight(constraints);
+    }
+}
diff --git a/server/src/main/java/org/opensearch/cluster/routing/allocation/allocator/BalancedShardsAllocator.java b/server/src/main/java/org/opensearch/cluster/routing/allocation/allocator/BalancedShardsAllocator.java
index d8761e9b1a78e..0ff0eeba7d394 100644
--- a/server/src/main/java/org/opensearch/cluster/routing/allocation/allocator/BalancedShardsAllocator.java
+++ b/server/src/main/java/org/opensearch/cluster/routing/allocation/allocator/BalancedShardsAllocator.java
@@ -42,7 +42,9 @@
 import org.opensearch.cluster.routing.UnassignedInfo.AllocationStatus;
 import org.opensearch.cluster.routing.allocation.AllocateUnassignedDecision;
 import org.opensearch.cluster.routing.allocation.AllocationConstraints;
+import org.opensearch.cluster.routing.allocation.ConstraintTypes;
 import org.opensearch.cluster.routing.allocation.MoveDecision;
+import org.opensearch.cluster.routing.allocation.RebalanceConstraints;
 import org.opensearch.cluster.routing.allocation.RoutingAllocation;
 import org.opensearch.cluster.routing.allocation.ShardAllocationDecision;
 import org.opensearch.common.inject.Inject;
@@ -58,9 +60,13 @@
 import java.util.Map;
 import java.util.Set;
 
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.CLUSTER_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID;
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID;
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.INDEX_SHARD_PER_NODE_BREACH_CONSTRAINT_ID;
+
 /**
  * The {@link BalancedShardsAllocator} re-balances the nodes allocations
- * within an cluster based on a {@link WeightFunction}. The clusters balance is defined by four parameters which can be set
+ * within a cluster based on a {@link WeightFunction}. The clusters balance is defined by four parameters which can be set
  * in the cluster update API that allows changes in real-time:
  * <ul><li><code>cluster.routing.allocation.balance.shard</code> - The <b>shard balance</b> defines the weight factor
  * for shards allocated on a {@link RoutingNode}</li>
@@ -68,6 +74,7 @@
  * of {@link org.opensearch.cluster.routing.ShardRouting}s per index allocated on a specific node</li>
  * <li><code>cluster.routing.allocation.balance.threshold</code> - A <b>threshold</b> to set the minimal optimization
  * value of operations that should be performed</li>
+ * <li><code>cluster.routing.allocation.balance.prefer_primary</code> - Defines whether primary shard balance is desired</li>
  * </ul>
  * <p>
  * These parameters are combined in a {@link WeightFunction} that allows calculation of node weights which
@@ -93,6 +100,10 @@ public class BalancedShardsAllocator implements ShardsAllocator {
         Property.Dynamic,
         Property.NodeScope
     );
+
+    /**
+     * Move primary shards first from node for shard movement when shards can not stay on node anymore. {@link LocalShardsBalancer#moveShards()}
+     */
     public static final Setting<Boolean> SHARD_MOVE_PRIMARY_FIRST_SETTING = Setting.boolSetting(
         "cluster.routing.allocation.move.primary_first",
         false,
@@ -107,7 +118,22 @@ public class BalancedShardsAllocator implements ShardsAllocator {
         Property.NodeScope
     );
 
+    /**
+     * This setting governs whether primary shards balance is desired during allocation. This is used by {@link ConstraintTypes#isPerIndexPrimaryShardsPerNodeBreached()}
+     * and {@link ConstraintTypes#isPrimaryShardsPerNodeBreached} which is used during unassigned shard allocation
+     * {@link LocalShardsBalancer#allocateUnassigned()} and shard re-balance/relocation to a different node via {@link LocalShardsBalancer#balance()} .
+     */
+
+    public static final Setting<Boolean> PREFER_PRIMARY_SHARD_BALANCE = Setting.boolSetting(
+        "cluster.routing.allocation.balance.prefer_primary",
+        false,
+        Property.Dynamic,
+        Property.NodeScope
+    );
+
     private volatile boolean movePrimaryFirst;
+
+    private volatile boolean preferPrimaryShardBalance;
     private volatile WeightFunction weightFunction;
     private volatile float threshold;
 
@@ -119,6 +145,8 @@ public BalancedShardsAllocator(Settings settings) {
     public BalancedShardsAllocator(Settings settings, ClusterSettings clusterSettings) {
         setWeightFunction(INDEX_BALANCE_FACTOR_SETTING.get(settings), SHARD_BALANCE_FACTOR_SETTING.get(settings));
         setThreshold(THRESHOLD_SETTING.get(settings));
+        setPreferPrimaryShardBalance(PREFER_PRIMARY_SHARD_BALANCE.get(settings));
+        clusterSettings.addSettingsUpdateConsumer(PREFER_PRIMARY_SHARD_BALANCE, this::setPreferPrimaryShardBalance);
         clusterSettings.addSettingsUpdateConsumer(SHARD_MOVE_PRIMARY_FIRST_SETTING, this::setMovePrimaryFirst);
         clusterSettings.addSettingsUpdateConsumer(INDEX_BALANCE_FACTOR_SETTING, SHARD_BALANCE_FACTOR_SETTING, this::setWeightFunction);
         clusterSettings.addSettingsUpdateConsumer(THRESHOLD_SETTING, this::setThreshold);
@@ -132,6 +160,17 @@ private void setWeightFunction(float indexBalance, float shardBalanceFactor) {
         weightFunction = new WeightFunction(indexBalance, shardBalanceFactor);
     }
 
+    /**
+     * When primary shards balance is desired, enable primary shard balancing constraints
+     * @param preferPrimaryShardBalance
+     */
+    private void setPreferPrimaryShardBalance(boolean preferPrimaryShardBalance) {
+        this.preferPrimaryShardBalance = preferPrimaryShardBalance;
+        this.weightFunction.updateAllocationConstraint(INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, preferPrimaryShardBalance);
+        this.weightFunction.updateAllocationConstraint(CLUSTER_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, preferPrimaryShardBalance);
+        this.weightFunction.updateRebalanceConstraint(INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, preferPrimaryShardBalance);
+    }
+
     private void setThreshold(float threshold) {
         this.threshold = threshold;
     }
@@ -142,7 +181,14 @@ public void allocate(RoutingAllocation allocation) {
             failAllocationOfNewPrimaries(allocation);
             return;
         }
-        final ShardsBalancer localShardsBalancer = new LocalShardsBalancer(logger, allocation, movePrimaryFirst, weightFunction, threshold);
+        final ShardsBalancer localShardsBalancer = new LocalShardsBalancer(
+            logger,
+            allocation,
+            movePrimaryFirst,
+            weightFunction,
+            threshold,
+            preferPrimaryShardBalance
+        );
         localShardsBalancer.allocateUnassigned();
         localShardsBalancer.moveShards();
         localShardsBalancer.balance();
@@ -157,7 +203,14 @@ public void allocate(RoutingAllocation allocation) {
 
     @Override
     public ShardAllocationDecision decideShardAllocation(final ShardRouting shard, final RoutingAllocation allocation) {
-        ShardsBalancer localShardsBalancer = new LocalShardsBalancer(logger, allocation, movePrimaryFirst, weightFunction, threshold);
+        ShardsBalancer localShardsBalancer = new LocalShardsBalancer(
+            logger,
+            allocation,
+            movePrimaryFirst,
+            weightFunction,
+            threshold,
+            preferPrimaryShardBalance
+        );
         AllocateUnassignedDecision allocateUnassignedDecision = AllocateUnassignedDecision.NOT_TAKEN;
         MoveDecision moveDecision = MoveDecision.NOT_TAKEN;
         if (shard.unassigned()) {
@@ -220,6 +273,13 @@ public float getShardBalance() {
         return weightFunction.shardBalance;
     }
 
+    /**
+     * Returns preferPrimaryShardBalance.
+     */
+    public boolean getPreferPrimaryBalance() {
+        return preferPrimaryShardBalance;
+    }
+
     /**
      * This class is the primary weight function used to create balanced over nodes and shards in the cluster.
      * Currently this function has 3 properties:
@@ -253,6 +313,7 @@ static class WeightFunction {
         private final float theta0;
         private final float theta1;
         private AllocationConstraints constraints;
+        private RebalanceConstraints rebalanceConstraints;
 
         WeightFunction(float indexBalance, float shardBalance) {
             float sum = indexBalance + shardBalance;
@@ -264,6 +325,9 @@ static class WeightFunction {
             this.indexBalance = indexBalance;
             this.shardBalance = shardBalance;
             this.constraints = new AllocationConstraints();
+            this.rebalanceConstraints = new RebalanceConstraints();
+            // Enable index shard per node breach constraint
+            updateAllocationConstraint(INDEX_SHARD_PER_NODE_BREACH_CONSTRAINT_ID, true);
         }
 
         public float weightWithAllocationConstraints(ShardsBalancer balancer, ModelNode node, String index) {
@@ -271,11 +335,24 @@ public float weightWithAllocationConstraints(ShardsBalancer balancer, ModelNode
             return balancerWeight + constraints.weight(balancer, node, index);
         }
 
+        public float weightWithRebalanceConstraints(ShardsBalancer balancer, ModelNode node, String index) {
+            float balancerWeight = weight(balancer, node, index);
+            return balancerWeight + rebalanceConstraints.weight(balancer, node, index);
+        }
+
         float weight(ShardsBalancer balancer, ModelNode node, String index) {
             final float weightShard = node.numShards() - balancer.avgShardsPerNode();
             final float weightIndex = node.numShards(index) - balancer.avgShardsPerNode(index);
             return theta0 * weightShard + theta1 * weightIndex;
         }
+
+        void updateAllocationConstraint(String constraint, boolean enable) {
+            this.constraints.updateAllocationConstraint(constraint, enable);
+        }
+
+        void updateRebalanceConstraint(String constraint, boolean add) {
+            this.rebalanceConstraints.updateRebalanceConstraint(constraint, add);
+        }
     }
 
     /**
@@ -313,6 +390,15 @@ public int numShards(String idx) {
             return index == null ? 0 : index.numShards();
         }
 
+        public int numPrimaryShards(String idx) {
+            ModelIndex index = indices.get(idx);
+            return index == null ? 0 : index.numPrimaryShards();
+        }
+
+        public int numPrimaryShards() {
+            return indices.values().stream().mapToInt(index -> index.numPrimaryShards()).sum();
+        }
+
         public int highestPrimary(String index) {
             ModelIndex idx = indices.get(index);
             if (idx != null) {
@@ -358,7 +444,6 @@ public boolean containsShard(ShardRouting shard) {
             ModelIndex index = getIndex(shard.getIndexName());
             return index == null ? false : index.containsShard(shard);
         }
-
     }
 
     /**
@@ -374,9 +459,10 @@ public Balancer(
             RoutingAllocation allocation,
             boolean movePrimaryFirst,
             BalancedShardsAllocator.WeightFunction weight,
-            float threshold
+            float threshold,
+            boolean preferPrimaryBalance
         ) {
-            super(logger, allocation, movePrimaryFirst, weight, threshold);
+            super(logger, allocation, movePrimaryFirst, weight, threshold, preferPrimaryBalance);
         }
     }
 
@@ -388,12 +474,17 @@ public Balancer(
     static final class ModelIndex implements Iterable<ShardRouting> {
         private final String id;
         private final Set<ShardRouting> shards = new HashSet<>(4); // expect few shards of same index to be allocated on same node
+        private final Set<ShardRouting> primaryShards = new HashSet<>();
         private int highestPrimary = -1;
 
         ModelIndex(String id) {
             this.id = id;
         }
 
+        public int numPrimaryShards() {
+            return primaryShards.size();
+        }
+
         public int highestPrimary() {
             if (highestPrimary == -1) {
                 int maxId = -1;
@@ -423,12 +514,20 @@ public Iterator<ShardRouting> iterator() {
         public void removeShard(ShardRouting shard) {
             highestPrimary = -1;
             assert shards.contains(shard) : "Shard not allocated on current node: " + shard;
+            if (shard.primary()) {
+                assert primaryShards.contains(shard) : "Primary shard not allocated on current node: " + shard;
+                primaryShards.remove(shard);
+            }
             shards.remove(shard);
         }
 
         public void addShard(ShardRouting shard) {
             highestPrimary = -1;
-            assert !shards.contains(shard) : "Shard already allocated on current node: " + shard;
+            assert shards.contains(shard) == false : "Shard already allocated on current node: " + shard;
+            if (shard.primary()) {
+                assert primaryShards.contains(shard) == false : "Primary shard already allocated on current node: " + shard;
+                primaryShards.add(shard);
+            }
             shards.add(shard);
         }
 
@@ -476,7 +575,7 @@ public void reset(String index) {
         }
 
         public float weight(ModelNode node) {
-            return function.weight(balancer, node, index);
+            return function.weightWithRebalanceConstraints(balancer, node, index);
         }
 
         @Override
diff --git a/server/src/main/java/org/opensearch/cluster/routing/allocation/allocator/LocalShardsBalancer.java b/server/src/main/java/org/opensearch/cluster/routing/allocation/allocator/LocalShardsBalancer.java
index 3c5e4013748af..0830f26be87f0 100644
--- a/server/src/main/java/org/opensearch/cluster/routing/allocation/allocator/LocalShardsBalancer.java
+++ b/server/src/main/java/org/opensearch/cluster/routing/allocation/allocator/LocalShardsBalancer.java
@@ -42,6 +42,7 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 import java.util.stream.StreamSupport;
 
 import static org.opensearch.cluster.routing.ShardRoutingState.RELOCATING;
@@ -58,11 +59,15 @@ public class LocalShardsBalancer extends ShardsBalancer {
     private final RoutingAllocation allocation;
     private final RoutingNodes routingNodes;
     private final boolean movePrimaryFirst;
+
+    private final boolean preferPrimaryBalance;
     private final BalancedShardsAllocator.WeightFunction weight;
 
     private final float threshold;
     private final Metadata metadata;
     private final float avgShardsPerNode;
+
+    private final float avgPrimaryShardsPerNode;
     private final BalancedShardsAllocator.NodeSorter sorter;
     private final Set<RoutingNode> inEligibleTargetNode;
 
@@ -71,7 +76,8 @@ public LocalShardsBalancer(
         RoutingAllocation allocation,
         boolean movePrimaryFirst,
         BalancedShardsAllocator.WeightFunction weight,
-        float threshold
+        float threshold,
+        boolean preferPrimaryBalance
     ) {
         this.logger = logger;
         this.allocation = allocation;
@@ -81,9 +87,13 @@ public LocalShardsBalancer(
         this.routingNodes = allocation.routingNodes();
         this.metadata = allocation.metadata();
         avgShardsPerNode = ((float) metadata.getTotalNumberOfShards()) / routingNodes.size();
+        avgPrimaryShardsPerNode = (float) (StreamSupport.stream(metadata.spliterator(), false)
+            .mapToInt(IndexMetadata::getNumberOfShards)
+            .sum()) / routingNodes.size();
         nodes = Collections.unmodifiableMap(buildModelFromAssigned());
         sorter = newNodeSorter();
         inEligibleTargetNode = new HashSet<>();
+        this.preferPrimaryBalance = preferPrimaryBalance;
     }
 
     /**
@@ -101,6 +111,16 @@ public float avgShardsPerNode(String index) {
         return ((float) metadata.index(index).getTotalNumberOfShards()) / nodes.size();
     }
 
+    @Override
+    public float avgPrimaryShardsPerNode(String index) {
+        return ((float) metadata.index(index).getNumberOfShards()) / nodes.size();
+    }
+
+    @Override
+    public float avgPrimaryShardsPerNode() {
+        return avgPrimaryShardsPerNode;
+    }
+
     /**
      * Returns the global average of shards per node
      */
@@ -223,7 +243,7 @@ MoveDecision decideRebalance(final ShardRouting shard) {
             // this is a comparison of the number of shards on this node to the number of shards
             // that should be on each node on average (both taking the cluster as a whole into account
             // as well as shards per index)
-            final float nodeWeight = weight.weight(this, node, idxName);
+            final float nodeWeight = weight.weightWithRebalanceConstraints(this, node, idxName);
             // if the node we are examining has a worse (higher) weight than the node the shard is
             // assigned to, then there is no way moving the shard to the node with the worse weight
             // can make the balance of the cluster better, so we check for that here
@@ -959,6 +979,7 @@ AllocateUnassignedDecision decideAllocateUnassigned(final ShardRouting shard) {
     }
 
     private static final Comparator<ShardRouting> BY_DESCENDING_SHARD_ID = Comparator.comparing(ShardRouting::shardId).reversed();
+    private static final Comparator<ShardRouting> PRIMARY_FIRST = Comparator.comparing(ShardRouting::primary).reversed();
 
     /**
      * Tries to find a relocation from the max node to the minimal node for an arbitrary shard of the given index on the
@@ -969,12 +990,16 @@ private boolean tryRelocateShard(BalancedShardsAllocator.ModelNode minNode, Bala
         final BalancedShardsAllocator.ModelIndex index = maxNode.getIndex(idx);
         if (index != null) {
             logger.trace("Try relocating shard of [{}] from [{}] to [{}]", idx, maxNode.getNodeId(), minNode.getNodeId());
-            final Iterable<ShardRouting> shardRoutings = StreamSupport.stream(index.spliterator(), false)
+            Stream<ShardRouting> routingStream = StreamSupport.stream(index.spliterator(), false)
                 .filter(ShardRouting::started) // cannot rebalance unassigned, initializing or relocating shards anyway
-                .filter(maxNode::containsShard)
-                .sorted(BY_DESCENDING_SHARD_ID) // check in descending order of shard id so that the decision is deterministic
-            ::iterator;
+                .filter(maxNode::containsShard) // check shards which are present on heaviest node
+                .sorted(BY_DESCENDING_SHARD_ID); // check in descending order of shard id so that the decision is deterministic
 
+            // If primary balance is preferred then prioritize moving primaries first
+            if (preferPrimaryBalance == true) {
+                routingStream = routingStream.sorted(PRIMARY_FIRST);
+            }
+            final Iterable<ShardRouting> shardRoutings = routingStream::iterator;
             final AllocationDeciders deciders = allocation.deciders();
             for (ShardRouting shard : shardRoutings) {
                 final Decision rebalanceDecision = deciders.canRebalance(shard, allocation);
@@ -985,9 +1010,15 @@ private boolean tryRelocateShard(BalancedShardsAllocator.ModelNode minNode, Bala
                 if (allocationDecision.type() == Decision.Type.NO) {
                     continue;
                 }
+                // This is a safety net which prevents un-necessary primary shard relocations from maxNode to minNode when
+                // doing such relocation wouldn't help in primary balance.
+                if (preferPrimaryBalance == true
+                    && shard.primary()
+                    && maxNode.numPrimaryShards(shard.getIndexName()) - minNode.numPrimaryShards(shard.getIndexName()) < 2) {
+                    continue;
+                }
 
                 final Decision decision = new Decision.Multi().add(allocationDecision).add(rebalanceDecision);
-
                 maxNode.removeShard(shard);
                 long shardSize = allocation.clusterInfo().getShardSize(shard, ShardRouting.UNAVAILABLE_EXPECTED_SHARD_SIZE);
 
diff --git a/server/src/main/java/org/opensearch/cluster/routing/allocation/allocator/ShardsBalancer.java b/server/src/main/java/org/opensearch/cluster/routing/allocation/allocator/ShardsBalancer.java
index 593e6998141fb..ef2dbd34644a7 100644
--- a/server/src/main/java/org/opensearch/cluster/routing/allocation/allocator/ShardsBalancer.java
+++ b/server/src/main/java/org/opensearch/cluster/routing/allocation/allocator/ShardsBalancer.java
@@ -72,4 +72,19 @@ public float avgShardsPerNode() {
     public float avgShardsPerNode(String index) {
         return Float.MAX_VALUE;
     }
+
+    /**
+     * Returns the average of primary shards per node for the given index
+     */
+    public float avgPrimaryShardsPerNode(String index) {
+        return Float.MAX_VALUE;
+    }
+
+    /**
+     * Returns the average of primary shards per node
+     */
+    public float avgPrimaryShardsPerNode() {
+        return Float.MAX_VALUE;
+    }
+
 }
diff --git a/server/src/main/java/org/opensearch/cluster/routing/allocation/decider/TargetPoolAllocationDecider.java b/server/src/main/java/org/opensearch/cluster/routing/allocation/decider/TargetPoolAllocationDecider.java
index c87f7d16079e9..c11f5823cf3a7 100644
--- a/server/src/main/java/org/opensearch/cluster/routing/allocation/decider/TargetPoolAllocationDecider.java
+++ b/server/src/main/java/org/opensearch/cluster/routing/allocation/decider/TargetPoolAllocationDecider.java
@@ -12,6 +12,7 @@
 import org.apache.logging.log4j.Logger;
 import org.opensearch.cluster.metadata.IndexMetadata;
 import org.opensearch.cluster.node.DiscoveryNode;
+import org.opensearch.cluster.node.DiscoveryNodeRole;
 import org.opensearch.cluster.routing.RoutingNode;
 import org.opensearch.cluster.routing.RoutingPool;
 import org.opensearch.cluster.routing.ShardRouting;
@@ -35,7 +36,7 @@ public Decision canAllocate(ShardRouting shardRouting, RoutingNode node, Routing
         if (RoutingPool.REMOTE_CAPABLE.equals(shardPool) && RoutingPool.LOCAL_ONLY.equals(targetNodePool)) {
             logger.debug(
                 "Shard: [{}] has target pool: [{}]. Cannot allocate on node: [{}] with target pool: [{}]",
-                shardRouting.shortSummary(),
+                shardRouting,
                 shardPool,
                 node.node(),
                 targetNodePool
@@ -47,7 +48,25 @@ public Decision canAllocate(ShardRouting shardRouting, RoutingNode node, Routing
                 shardPool,
                 targetNodePool
             );
-        }
+        } else if (RoutingPool.LOCAL_ONLY.equals(shardPool)
+            && RoutingPool.REMOTE_CAPABLE.equals(targetNodePool)
+            && !node.node().getRoles().contains(DiscoveryNodeRole.DATA_ROLE)) {
+                logger.debug(
+                    "Shard: [{}] has target pool: [{}]. Cannot allocate on node: [{}] without the [{}] node role",
+                    shardRouting,
+                    shardPool,
+                    node.node(),
+                    DiscoveryNodeRole.DATA_ROLE
+                );
+                return allocation.decision(
+                    Decision.NO,
+                    NAME,
+                    "Routing pools are incompatible. Shard pool: [{}], Node Pool: [{}] without [{}] role",
+                    shardPool,
+                    targetNodePool,
+                    DiscoveryNodeRole.DATA_ROLE
+                );
+            }
         return allocation.decision(
             Decision.YES,
             NAME,
@@ -91,7 +110,25 @@ private Decision canAllocateInTargetPool(IndexMetadata indexMetadata, DiscoveryN
                 indexPool,
                 targetNodePool
             );
-        }
+        } else if (RoutingPool.LOCAL_ONLY.equals(indexPool)
+            && RoutingPool.REMOTE_CAPABLE.equals(targetNodePool)
+            && !node.getRoles().contains(DiscoveryNodeRole.DATA_ROLE)) {
+                logger.debug(
+                    "Index: [{}] has target pool: [{}]. Cannot allocate on node: [{}] without the [{}] node role",
+                    indexMetadata.getIndex().getName(),
+                    indexPool,
+                    node,
+                    DiscoveryNodeRole.DATA_ROLE
+                );
+                return allocation.decision(
+                    Decision.NO,
+                    NAME,
+                    "Routing pools are incompatible. Index pool: [{}], Node Pool: [{}] without [{}] role",
+                    indexPool,
+                    targetNodePool,
+                    DiscoveryNodeRole.DATA_ROLE
+                );
+            }
         return allocation.decision(
             Decision.YES,
             NAME,
diff --git a/server/src/main/java/org/opensearch/cluster/service/MasterService.java b/server/src/main/java/org/opensearch/cluster/service/MasterService.java
index 780f12c12f134..03bc3219ac8f8 100644
--- a/server/src/main/java/org/opensearch/cluster/service/MasterService.java
+++ b/server/src/main/java/org/opensearch/cluster/service/MasterService.java
@@ -905,11 +905,9 @@ private ClusterTasksResult<Object> executeTasks(TaskInputs taskInputs, ClusterSt
         );
         if (Assertions.ENABLED) {
             ClusterTasksResult<Object> finalClusterTasksResult = clusterTasksResult;
-            taskInputs.updateTasks.forEach(
-                updateTask -> {
-                    assert finalClusterTasksResult.executionResults.containsKey(updateTask.task) : "missing task result for " + updateTask;
-                }
-            );
+            taskInputs.updateTasks.forEach(updateTask -> {
+                assert finalClusterTasksResult.executionResults.containsKey(updateTask.task) : "missing task result for " + updateTask;
+            });
         }
 
         return clusterTasksResult;
diff --git a/server/src/main/java/org/opensearch/cluster/service/TaskBatcher.java b/server/src/main/java/org/opensearch/cluster/service/TaskBatcher.java
index b5710bab41172..ed744f4f42d07 100644
--- a/server/src/main/java/org/opensearch/cluster/service/TaskBatcher.java
+++ b/server/src/main/java/org/opensearch/cluster/service/TaskBatcher.java
@@ -46,6 +46,7 @@
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.function.Function;
 import java.util.stream.Collectors;
@@ -61,7 +62,7 @@ public abstract class TaskBatcher {
     private final Logger logger;
     private final PrioritizedOpenSearchThreadPoolExecutor threadExecutor;
     // package visible for tests
-    final Map<Object, LinkedHashSet<BatchedTask>> tasksPerBatchingKey = new HashMap<>();
+    final Map<Object, LinkedHashSet<BatchedTask>> tasksPerBatchingKey = new ConcurrentHashMap<>();
     private final TaskBatcherListener taskBatcherListener;
 
     public TaskBatcher(Logger logger, PrioritizedOpenSearchThreadPoolExecutor threadExecutor, TaskBatcherListener taskBatcherListener) {
@@ -85,20 +86,11 @@ public void submitTasks(List<? extends BatchedTask> tasks, @Nullable TimeValue t
         try {
             // convert to an identity map to check for dups based on task identity
             final Map<Object, BatchedTask> tasksIdentity = tasks.stream()
-                .collect(
-                    Collectors.toMap(
-                        BatchedTask::getTask,
-                        Function.identity(),
-                        (a, b) -> { throw new IllegalStateException("cannot add duplicate task: " + a); },
-                        IdentityHashMap::new
-                    )
-                );
-
-            synchronized (tasksPerBatchingKey) {
-                LinkedHashSet<BatchedTask> existingTasks = tasksPerBatchingKey.computeIfAbsent(
-                    firstTask.batchingKey,
-                    k -> new LinkedHashSet<>(tasks.size())
-                );
+                .collect(Collectors.toMap(BatchedTask::getTask, Function.identity(), (a, b) -> {
+                    throw new IllegalStateException("cannot add duplicate task: " + a);
+                }, IdentityHashMap::new));
+            LinkedHashSet<BatchedTask> newTasks = new LinkedHashSet<>(tasks);
+            tasksPerBatchingKey.merge(firstTask.batchingKey, newTasks, (existingTasks, updatedTasks) -> {
                 for (BatchedTask existing : existingTasks) {
                     // check that there won't be two tasks with the same identity for the same batching key
                     BatchedTask duplicateTask = tasksIdentity.get(existing.getTask());
@@ -112,8 +104,9 @@ public void submitTasks(List<? extends BatchedTask> tasks, @Nullable TimeValue t
                         );
                     }
                 }
-                existingTasks.addAll(tasks);
-            }
+                existingTasks.addAll(updatedTasks);
+                return existingTasks;
+            });
         } catch (Exception e) {
             taskBatcherListener.onSubmitFailure(tasks);
             throw e;
@@ -139,15 +132,13 @@ private void onTimeoutInternal(List<? extends BatchedTask> tasks, TimeValue time
             Object batchingKey = firstTask.batchingKey;
             assert tasks.stream().allMatch(t -> t.batchingKey == batchingKey)
                 : "tasks submitted in a batch should share the same batching key: " + tasks;
-            synchronized (tasksPerBatchingKey) {
-                LinkedHashSet<BatchedTask> existingTasks = tasksPerBatchingKey.get(batchingKey);
-                if (existingTasks != null) {
-                    existingTasks.removeAll(toRemove);
-                    if (existingTasks.isEmpty()) {
-                        tasksPerBatchingKey.remove(batchingKey);
-                    }
+            tasksPerBatchingKey.computeIfPresent(batchingKey, (tasksKey, existingTasks) -> {
+                existingTasks.removeAll(toRemove);
+                if (existingTasks.isEmpty()) {
+                    return null;
                 }
-            }
+                return existingTasks;
+            });
             taskBatcherListener.onTimeout(toRemove);
             onTimeout(toRemove, timeout);
         }
@@ -165,17 +156,15 @@ void runIfNotProcessed(BatchedTask updateTask) {
         if (updateTask.processed.get() == false) {
             final List<BatchedTask> toExecute = new ArrayList<>();
             final Map<String, List<BatchedTask>> processTasksBySource = new HashMap<>();
-            synchronized (tasksPerBatchingKey) {
-                LinkedHashSet<BatchedTask> pending = tasksPerBatchingKey.remove(updateTask.batchingKey);
-                if (pending != null) {
-                    for (BatchedTask task : pending) {
-                        if (task.processed.getAndSet(true) == false) {
-                            logger.trace("will process {}", task);
-                            toExecute.add(task);
-                            processTasksBySource.computeIfAbsent(task.source, s -> new ArrayList<>()).add(task);
-                        } else {
-                            logger.trace("skipping {}, already processed", task);
-                        }
+            LinkedHashSet<BatchedTask> pending = tasksPerBatchingKey.remove(updateTask.batchingKey);
+            if (pending != null) {
+                for (BatchedTask task : pending) {
+                    if (task.processed.getAndSet(true) == false) {
+                        logger.trace("will process {}", task);
+                        toExecute.add(task);
+                        processTasksBySource.computeIfAbsent(task.source, s -> new ArrayList<>()).add(task);
+                    } else {
+                        logger.trace("skipping {}, already processed", task);
                     }
                 }
             }
diff --git a/server/src/main/java/org/opensearch/common/logging/OpenSearchJsonLayout.java b/server/src/main/java/org/opensearch/common/logging/OpenSearchJsonLayout.java
index a1b014a81be64..dac9e299e9b7e 100644
--- a/server/src/main/java/org/opensearch/common/logging/OpenSearchJsonLayout.java
+++ b/server/src/main/java/org/opensearch/common/logging/OpenSearchJsonLayout.java
@@ -83,6 +83,9 @@
  * <p>
  * The value taken from %OpenSearchMessageField{message} has to be a simple escaped JSON value and is populated in subclasses of
  * <code>OpenSearchLogMessage</code>
+ * <p>
+ * The <code>message</code> field is truncated at 10000 characters by default. This limit can be controlled by setting the
+ * <code>appender.logger.layout.maxmessagelength</code> to the desired limit or to <code>0</code> to disable truncation.
  *
  * @opensearch.internal
  */
@@ -91,18 +94,26 @@ public class OpenSearchJsonLayout extends AbstractStringLayout {
 
     private final PatternLayout patternLayout;
 
-    protected OpenSearchJsonLayout(String typeName, Charset charset, String[] opensearchMessageFields) {
+    protected OpenSearchJsonLayout(String typeName, Charset charset, String[] opensearchMessageFields, int maxMessageLength) {
         super(charset);
         this.patternLayout = PatternLayout.newBuilder()
-            .withPattern(pattern(typeName, opensearchMessageFields))
+            .withPattern(pattern(typeName, opensearchMessageFields, maxMessageLength))
             .withAlwaysWriteExceptions(false)
             .build();
     }
 
-    private String pattern(String type, String[] opensearchMessageFields) {
+    private String pattern(String type, String[] opensearchMessageFields, int maxMessageLength) {
         if (Strings.isEmpty(type)) {
             throw new IllegalArgumentException("layout parameter 'type_name' cannot be empty");
         }
+
+        String messageFormat = "%m";
+        if (maxMessageLength < 0) {
+            throw new IllegalArgumentException("layout parameter 'maxmessagelength' cannot be a negative number");
+        } else if (maxMessageLength > 0) {
+            messageFormat = "%.-" + Integer.toString(maxMessageLength) + "m";
+        }
+
         Map<String, Object> map = new LinkedHashMap<>();
         map.put("type", inQuotes(type));
         map.put("timestamp", inQuotes("%d{yyyy-MM-dd'T'HH:mm:ss,SSSZZ}"));
@@ -110,7 +121,7 @@ private String pattern(String type, String[] opensearchMessageFields) {
         map.put("component", inQuotes("%c{1.}"));
         map.put("cluster.name", inQuotes("${sys:opensearch.logs.cluster_name}"));
         map.put("node.name", inQuotes("%node_name"));
-        map.put("message", inQuotes("%notEmpty{%enc{%marker}{JSON} }%enc{%.-10000m}{JSON}"));
+        map.put("message", inQuotes("%notEmpty{%enc{%marker}{JSON} }%enc{" + messageFormat + "}{JSON}"));
 
         for (String key : opensearchMessageFields) {
             map.put(key, inQuotes("%OpenSearchMessageField{" + key + "}"));
@@ -162,8 +173,8 @@ private String inQuotes(String s) {
     }
 
     @PluginFactory
-    public static OpenSearchJsonLayout createLayout(String type, Charset charset, String[] opensearchmessagefields) {
-        return new OpenSearchJsonLayout(type, charset, opensearchmessagefields);
+    public static OpenSearchJsonLayout createLayout(String type, Charset charset, String[] opensearchmessagefields, int maxMessageLength) {
+        return new OpenSearchJsonLayout(type, charset, opensearchmessagefields, maxMessageLength);
     }
 
     PatternLayout getPatternLayout() {
@@ -188,14 +199,18 @@ public static class Builder<B extends OpenSearchJsonLayout.Builder<B>> extends A
         @PluginAttribute("opensearchmessagefields")
         private String opensearchMessageFields;
 
+        @PluginAttribute(value = "maxmessagelength", defaultInt = 10000)
+        private int maxMessageLength;
+
         public Builder() {
             setCharset(StandardCharsets.UTF_8);
+            setMaxMessageLength(10000);
         }
 
         @Override
         public OpenSearchJsonLayout build() {
             String[] split = Strings.isNullOrEmpty(opensearchMessageFields) ? new String[] {} : opensearchMessageFields.split(",");
-            return OpenSearchJsonLayout.createLayout(type, charset, split);
+            return OpenSearchJsonLayout.createLayout(type, charset, split, maxMessageLength);
         }
 
         public Charset getCharset() {
@@ -224,6 +239,15 @@ public B setOpenSearchMessageFields(String opensearchMessageFields) {
             this.opensearchMessageFields = opensearchMessageFields;
             return asBuilder();
         }
+
+        public int getMaxMessageLength() {
+            return maxMessageLength;
+        }
+
+        public B setMaxMessageLength(final int maxMessageLength) {
+            this.maxMessageLength = maxMessageLength;
+            return asBuilder();
+        }
     }
 
     @PluginBuilderFactory
diff --git a/server/src/main/java/org/opensearch/common/settings/ClusterSettings.java b/server/src/main/java/org/opensearch/common/settings/ClusterSettings.java
index cd062b630a8e6..a2c145fb7e8b7 100644
--- a/server/src/main/java/org/opensearch/common/settings/ClusterSettings.java
+++ b/server/src/main/java/org/opensearch/common/settings/ClusterSettings.java
@@ -40,6 +40,7 @@
 import org.opensearch.index.IndexModule;
 import org.opensearch.index.IndexSettings;
 import org.opensearch.index.IndexingPressure;
+import org.opensearch.index.SegmentReplicationPressureService;
 import org.opensearch.index.ShardIndexingPressureMemoryManager;
 import org.opensearch.index.ShardIndexingPressureSettings;
 import org.opensearch.index.ShardIndexingPressureStore;
@@ -233,6 +234,7 @@ public void apply(Settings value, Settings current, Settings previous) {
                 AwarenessReplicaBalance.CLUSTER_ROUTING_ALLOCATION_AWARENESS_BALANCE_SETTING,
                 BalancedShardsAllocator.INDEX_BALANCE_FACTOR_SETTING,
                 BalancedShardsAllocator.SHARD_BALANCE_FACTOR_SETTING,
+                BalancedShardsAllocator.PREFER_PRIMARY_SHARD_BALANCE,
                 BalancedShardsAllocator.SHARD_MOVE_PRIMARY_FIRST_SETTING,
                 BalancedShardsAllocator.THRESHOLD_SETTING,
                 BreakerSettings.CIRCUIT_BREAKER_LIMIT_SETTING,
@@ -625,7 +627,11 @@ public void apply(Settings value, Settings current, Settings previous) {
                 SearchShardTaskSettings.SETTING_TOTAL_HEAP_PERCENT_THRESHOLD,
                 SearchBackpressureSettings.SETTING_CANCELLATION_RATIO,  // deprecated
                 SearchBackpressureSettings.SETTING_CANCELLATION_RATE,   // deprecated
-                SearchBackpressureSettings.SETTING_CANCELLATION_BURST   // deprecated
+                SearchBackpressureSettings.SETTING_CANCELLATION_BURST,   // deprecated
+                SegmentReplicationPressureService.SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED,
+                SegmentReplicationPressureService.MAX_INDEXING_CHECKPOINTS,
+                SegmentReplicationPressureService.MAX_REPLICATION_TIME_SETTING,
+                SegmentReplicationPressureService.MAX_ALLOWED_STALE_SHARDS
             )
         )
     );
diff --git a/server/src/main/java/org/opensearch/common/settings/Setting.java b/server/src/main/java/org/opensearch/common/settings/Setting.java
index 26a60e24b86b2..35063d89a68e1 100644
--- a/server/src/main/java/org/opensearch/common/settings/Setting.java
+++ b/server/src/main/java/org/opensearch/common/settings/Setting.java
@@ -40,6 +40,9 @@
 import org.opensearch.common.Nullable;
 import org.opensearch.common.Strings;
 import org.opensearch.common.collect.Tuple;
+import org.opensearch.common.io.stream.StreamInput;
+import org.opensearch.common.io.stream.StreamOutput;
+import org.opensearch.common.io.stream.Writeable;
 import org.opensearch.common.regex.Regex;
 import org.opensearch.common.unit.ByteSizeValue;
 import org.opensearch.common.unit.MemorySizeValue;
@@ -166,8 +169,8 @@ public enum Property {
     protected final Function<Settings, String> defaultValue;
     @Nullable
     protected final Setting<T> fallbackSetting;
-    private final Function<String, T> parser;
-    private final Validator<T> validator;
+    protected final Function<String, T> parser;
+    protected final Validator<T> validator;
     private final EnumSet<Property> properties;
 
     private static final EnumSet<Property> EMPTY_PROPERTIES = EnumSet.noneOf(Property.class);
@@ -1247,6 +1250,40 @@ private static boolean isFiltered(Property[] properties) {
         return properties != null && Arrays.asList(properties).contains(Property.Filtered);
     }
 
+    /**
+     * A writeable validator able to check the value of string type custom setting by using regular expression
+     */
+    public static class RegexValidator implements Writeable, Validator<String> {
+        private Pattern pattern;
+
+        /**
+         * @param regex A regular expression containing the only valid input for this setting.
+         */
+        public RegexValidator(String regex) {
+            this.pattern = Pattern.compile(regex);
+        }
+
+        public RegexValidator(StreamInput in) throws IOException {
+            this.pattern = Pattern.compile(in.readString());
+        }
+
+        Pattern getPattern() {
+            return pattern;
+        }
+
+        @Override
+        public void validate(String value) {
+            if (!pattern.matcher(value).matches()) {
+                throw new IllegalArgumentException("Setting [" + value + "] does not match regex [" + pattern.pattern() + "]");
+            }
+        }
+
+        @Override
+        public void writeTo(StreamOutput out) throws IOException {
+            out.writeString(pattern.pattern());
+        }
+    }
+
     // Float
 
     private static float parseFloat(String s, float minValue, float maxValue, String key, boolean isFiltered) {
@@ -1287,12 +1324,80 @@ public static Setting<Float> floatSetting(
         return new Setting<>(
             key,
             Float.toString(defaultValue),
-            (s) -> parseFloat(s, minValue, maxValue, key, isFiltered(properties)),
+            new FloatParser(minValue, maxValue, key, isFiltered(properties)),
             validator,
             properties
         );
     }
 
+    /**
+     * A writeable parser for float
+     *
+     */
+    public static class FloatParser implements Function<String, Float>, Writeable {
+        private float minValue;
+        private float maxValue;
+        private String key;
+        private boolean isFiltered;
+
+        public FloatParser(float minValue, float maxValue, String key, boolean isFiltered) {
+            this.minValue = minValue;
+            this.maxValue = maxValue;
+            this.key = key;
+            this.isFiltered = isFiltered;
+        }
+
+        public FloatParser(StreamInput in) throws IOException {
+            minValue = in.readFloat();
+            maxValue = in.readFloat();
+            key = in.readString();
+            isFiltered = in.readBoolean();
+        }
+
+        @Override
+        public void writeTo(StreamOutput out) throws IOException {
+            out.writeFloat(minValue);
+            out.writeFloat(maxValue);
+            out.writeString(key);
+            out.writeBoolean(isFiltered);
+        }
+
+        public float getMin() {
+            return minValue;
+        }
+
+        public float getMax() {
+            return maxValue;
+        }
+
+        public String getKey() {
+            return key;
+        }
+
+        public boolean getFilterStatus() {
+            return isFiltered;
+        }
+
+        @Override
+        public Float apply(String s) {
+            return parseFloat(s, minValue, maxValue, key, isFiltered);
+        }
+
+        public boolean equals(Object obj) {
+            if (this == obj) return true;
+            if (obj == null || getClass() != obj.getClass()) return false;
+            FloatParser that = (FloatParser) obj;
+            return Objects.equals(key, that.key)
+                && Objects.equals(minValue, that.minValue)
+                && Objects.equals(maxValue, that.maxValue)
+                && Objects.equals(isFiltered, that.isFiltered);
+        }
+
+        public int hashCode() {
+            return Objects.hash(minValue, maxValue, key, isFiltered);
+        }
+    }
+
     // Setting<Float> with fallback
 
     public static Setting<Float> floatSetting(String key, Setting<Float> fallbackSetting, Property... properties) {
@@ -1389,12 +1494,80 @@ public static Setting<Integer> intSetting(
         return new Setting<>(
             key,
             Integer.toString(defaultValue),
-            (s) -> parseInt(s, minValue, maxValue, key, isFiltered(properties)),
+            new IntegerParser(minValue, maxValue, key, isFiltered(properties)),
             validator,
             properties
         );
     }
 
+    /**
+     * A writeable parser for integer
+     *
+     */
+    public static class IntegerParser implements Function<String, Integer>, Writeable {
+        private String key;
+        private int minValue;
+        private int maxValue;
+        private boolean isFiltered;
+
+        public IntegerParser(int minValue, int maxValue, String key, boolean isFiltered) {
+            this.minValue = minValue;
+            this.maxValue = maxValue;
+            this.key = key;
+            this.isFiltered = isFiltered;
+        }
+
+        public IntegerParser(StreamInput in) throws IOException {
+            minValue = in.readInt();
+            maxValue = in.readInt();
+            key = in.readString();
+            isFiltered = in.readBoolean();
+        }
+
+        @Override
+        public void writeTo(StreamOutput out) throws IOException {
+            out.writeInt(minValue);
+            out.writeInt(maxValue);
+            out.writeString(key);
+            out.writeBoolean(isFiltered);
+        }
+
+        public int getMin() {
+            return minValue;
+        }
+
+        public int getMax() {
+            return maxValue;
+        }
+
+        public String getKey() {
+            return key;
+        }
+
+        public boolean getFilterStatus() {
+            return isFiltered;
+        }
+
+        @Override
+        public Integer apply(String s) {
+            return parseInt(s, minValue, maxValue, key, isFiltered);
+        }
+
+        public boolean equals(Object obj) {
+            if (this == obj) return true;
+            if (obj == null || getClass() != obj.getClass()) return false;
+            IntegerParser that = (IntegerParser) obj;
+            return Objects.equals(key, that.key)
+                && Objects.equals(minValue, that.minValue)
+                && Objects.equals(maxValue, that.maxValue)
+                && Objects.equals(isFiltered, that.isFiltered);
+        }
+
+        public int hashCode() {
+            return Objects.hash(minValue, maxValue, key, isFiltered);
+        }
+    }
+
     // Setting<Integer> with fallback
 
     public static Setting<Integer> intSetting(String key, Setting<Integer> fallbackSetting, Property... properties) {
@@ -1483,12 +1656,80 @@ public static Setting<Long> longSetting(
         return new Setting<>(
             key,
             Long.toString(defaultValue),
-            (s) -> parseLong(s, minValue, maxValue, key, isFiltered(properties)),
+            new LongParser(minValue, maxValue, key, isFiltered(properties)),
             validator,
             properties
         );
     }
 
+    /**
+     * A writeable parser for long
+     *
+     */
+    public static class LongParser implements Function<String, Long>, Writeable {
+        private String key;
+        private long minValue;
+        private long maxValue;
+        private boolean isFiltered;
+
+        public LongParser(long minValue, long maxValue, String key, boolean isFiltered) {
+            this.minValue = minValue;
+            this.maxValue = maxValue;
+            this.key = key;
+            this.isFiltered = isFiltered;
+        }
+
+        public LongParser(StreamInput in) throws IOException {
+            minValue = in.readLong();
+            maxValue = in.readLong();
+            key = in.readString();
+            isFiltered = in.readBoolean();
+        }
+
+        @Override
+        public void writeTo(StreamOutput out) throws IOException {
+            out.writeLong(minValue);
+            out.writeLong(maxValue);
+            out.writeString(key);
+            out.writeBoolean(isFiltered);
+        }
+
+        public long getMin() {
+            return minValue;
+        }
+
+        public long getMax() {
+            return maxValue;
+        }
+
+        public String getKey() {
+            return key;
+        }
+
+        public boolean getFilterStatus() {
+            return isFiltered;
+        }
+
+        @Override
+        public Long apply(String s) {
+            return parseLong(s, minValue, maxValue, key, isFiltered);
+        }
+
+        public boolean equals(Object obj) {
+            if (this == obj) return true;
+            if (obj == null || getClass() != obj.getClass()) return false;
+            LongParser that = (LongParser) obj;
+            return Objects.equals(key, that.key)
+                && Objects.equals(minValue, that.minValue)
+                && Objects.equals(maxValue, that.maxValue)
+                && Objects.equals(isFiltered, that.isFiltered);
+        }
+
+        public int hashCode() {
+            return Objects.hash(minValue, maxValue, key, isFiltered);
+        }
+    }
+
     // Setting<Long> with fallback
 
     public static Setting<Long> longSetting(String key, Setting<Long> fallbackSetting, Property... properties) {
@@ -1577,12 +1818,80 @@ public static Setting<Double> doubleSetting(
         return new Setting<>(
             key,
             Double.toString(defaultValue),
-            (s) -> parseDouble(s, minValue, maxValue, key, isFiltered(properties)),
+            new DoubleParser(minValue, maxValue, key, isFiltered(properties)),
             validator,
             properties
         );
     }
 
+    /**
+     * A writeable parser for double
+     *
+     */
+    public static class DoubleParser implements Function<String, Double>, Writeable {
+        private double minValue;
+        private double maxValue;
+        private String key;
+        private boolean isFiltered;
+
+        public DoubleParser(double minValue, double maxValue, String key, boolean isFiltered) {
+            this.minValue = minValue;
+            this.maxValue = maxValue;
+            this.key = key;
+            this.isFiltered = isFiltered;
+        }
+
+        public DoubleParser(StreamInput in) throws IOException {
+            minValue = in.readDouble();
+            maxValue = in.readDouble();
+            key = in.readString();
+            isFiltered = in.readBoolean();
+        }
+
+        @Override
+        public void writeTo(StreamOutput out) throws IOException {
+            out.writeDouble(minValue);
+            out.writeDouble(maxValue);
+            out.writeString(key);
+            out.writeBoolean(isFiltered);
+        }
+
+        public double getMin() {
+            return minValue;
+        }
+
+        public double getMax() {
+            return maxValue;
+        }
+
+        public String getKey() {
+            return key;
+        }
+
+        public boolean getFilterStatus() {
+            return isFiltered;
+        }
+
+        @Override
+        public Double apply(String s) {
+            return parseDouble(s, minValue, maxValue, key, isFiltered);
+        }
+
+        public boolean equals(Object obj) {
+            if (this == obj) return true;
+            if (obj == null || getClass() != obj.getClass()) return false;
+            DoubleParser that = (DoubleParser) obj;
+            return Objects.equals(key, that.key)
+                && Objects.equals(minValue, that.minValue)
+                && Objects.equals(maxValue, that.maxValue)
+                && Objects.equals(isFiltered, that.isFiltered);
+        }
+
+        public int hashCode() {
+            return Objects.hash(minValue, maxValue, key, isFiltered);
+        }
+    }
+
     // Setting<Double> with fallback
 
     public static Setting<Double> doubleSetting(String key, Setting<Double> fallbackSetting, Property... properties) {
@@ -1722,11 +2031,11 @@ public static Setting<ByteSizeValue> byteSizeSetting(String key, ByteSizeValue v
     }
 
     public static Setting<ByteSizeValue> byteSizeSetting(String key, Setting<ByteSizeValue> fallbackSetting, Property... properties) {
-        return new Setting<>(key, fallbackSetting, (s) -> ByteSizeValue.parseBytesSizeValue(s, key), properties);
+        return new Setting<>(key, fallbackSetting, new ByteSizeValueParser(key), properties);
     }
 
     public static Setting<ByteSizeValue> byteSizeSetting(String key, Function<Settings, String> defaultValue, Property... properties) {
-        return new Setting<>(key, defaultValue, (s) -> ByteSizeValue.parseBytesSizeValue(s, key), properties);
+        return new Setting<>(key, defaultValue, new ByteSizeValueParser(key), properties);
     }
 
     public static Setting<ByteSizeValue> byteSizeSetting(
@@ -1746,7 +2055,68 @@ public static Setting<ByteSizeValue> byteSizeSetting(
         ByteSizeValue maxValue,
         Property... properties
     ) {
-        return new Setting<>(key, defaultValue, (s) -> parseByteSize(s, minValue, maxValue, key), properties);
+        return new Setting<>(key, defaultValue, new ByteSizeValueParser(minValue, maxValue, key), properties);
+    }
+
+    /**
+     * A writeable parser for bytesizevalue
+     *
+     */
+    public static class ByteSizeValueParser implements Function<String, ByteSizeValue>, Writeable {
+        private ByteSizeValue minValue;
+        private ByteSizeValue maxValue;
+        private String key;
+
+        public ByteSizeValueParser(ByteSizeValue minValue, ByteSizeValue maxValue, String key) {
+            this.minValue = minValue;
+            this.maxValue = maxValue;
+            this.key = key;
+        }
+
+        public ByteSizeValueParser(String key) {
+            this(new ByteSizeValue(-1), new ByteSizeValue(Long.MAX_VALUE), key);
+        }
+
+        public ByteSizeValueParser(StreamInput in) throws IOException {
+            minValue = new ByteSizeValue(in);
+            maxValue = new ByteSizeValue(in);
+            key = in.readString();
+        }
+
+        @Override
+        public void writeTo(StreamOutput out) throws IOException {
+            ((ByteSizeValue) minValue).writeTo(out);
+            ((ByteSizeValue) maxValue).writeTo(out);
+            out.writeString(key);
+        }
+
+        public ByteSizeValue getMin() {
+            return minValue;
+        }
+
+        public ByteSizeValue getMax() {
+            return maxValue;
+        }
+
+        public String getKey() {
+            return key;
+        }
+
+        @Override
+        public ByteSizeValue apply(String s) {
+            return parseByteSize(s, minValue, maxValue, key);
+        }
+
+        public boolean equals(Object obj) {
+            if (this == obj) return true;
+            if (obj == null || getClass() != obj.getClass()) return false;
+            ByteSizeValueParser that = (ByteSizeValueParser) obj;
+            return Objects.equals(key, that.key) && Objects.equals(minValue, that.minValue) && Objects.equals(maxValue, that.maxValue);
+        }
+
+        public int hashCode() {
+            return Objects.hash(key, minValue, maxValue);
+        }
     }
 
     public static ByteSizeValue parseByteSize(String s, ByteSizeValue minValue, ByteSizeValue maxValue, String key) {
@@ -1799,7 +2169,7 @@ public static Setting<ByteSizeValue> memorySizeSetting(String key, ByteSizeValue
      * @return the setting object
      */
     public static Setting<ByteSizeValue> memorySizeSetting(String key, Function<Settings, String> defaultValue, Property... properties) {
-        return new Setting<>(key, defaultValue, (s) -> MemorySizeValue.parseBytesSizeValueOrHeapRatio(s, key), properties);
+        return new Setting<>(key, defaultValue, new MemorySizeValueParser(key), properties);
     }
 
     /**
@@ -1813,7 +2183,47 @@ public static Setting<ByteSizeValue> memorySizeSetting(String key, Function<Sett
      * @return the setting object
      */
     public static Setting<ByteSizeValue> memorySizeSetting(String key, String defaultPercentage, Property... properties) {
-        return new Setting<>(key, (s) -> defaultPercentage, (s) -> MemorySizeValue.parseBytesSizeValueOrHeapRatio(s, key), properties);
+        return new Setting<>(key, (s) -> defaultPercentage, new MemorySizeValueParser(key), properties);
+    }
+
+    /**
+     * A writeable parser for memory size value
+     */
+    public static class MemorySizeValueParser implements Function<String, ByteSizeValue>, Writeable {
+        private String key;
+
+        public MemorySizeValueParser(String key) {
+            this.key = key;
+        }
+
+        public MemorySizeValueParser(StreamInput in) throws IOException {
+            key = in.readString();
+        }
+
+        @Override
+        public void writeTo(StreamOutput out) throws IOException {
+            out.writeString(key);
+        }
+
+        public String getKey() {
+            return key;
+        }
+
+        @Override
+        public ByteSizeValue apply(String s) {
+            return MemorySizeValue.parseBytesSizeValueOrHeapRatio(s, key);
+        }
+
+        public boolean equals(Object obj) {
+            if (this == obj) return true;
+            if (obj == null || getClass() != obj.getClass()) return false;
+            MemorySizeValueParser that = (MemorySizeValueParser) obj;
+            return Objects.equals(key, that.key);
+        }
+
+        public int hashCode() {
+            return Objects.hash(key);
+        }
     }
 
     /**
@@ -2073,6 +2483,63 @@ public static Setting<TimeValue> timeSetting(
         );
     }
 
+    /**
+     * A writeable parser for time value only has min value
+     *
+     */
+    public static class MinTimeValueParser implements Function<String, TimeValue>, Writeable {
+        private String key;
+        private TimeValue minValue;
+        private boolean isFiltered;
+
+        public MinTimeValueParser(String key, TimeValue minValue, boolean isFiltered) {
+            this.key = key;
+            this.minValue = minValue;
+            this.isFiltered = isFiltered;
+        }
+
+        public MinTimeValueParser(StreamInput in) throws IOException {
+            key = in.readString();
+            minValue = in.readTimeValue();
+            isFiltered = in.readBoolean();
+        }
+
+        @Override
+        public void writeTo(StreamOutput out) throws IOException {
+            out.writeString(key);
+            out.writeTimeValue(minValue);
+            out.writeBoolean(isFiltered);
+        }
+
+        public TimeValue getMin() {
+            return minValue;
+        }
+
+        public String getKey() {
+            return key;
+        }
+
+        public boolean getFilterStatus() {
+            return isFiltered;
+        }
+
+        @Override
+        public TimeValue apply(String s) {
+            return minTimeValueParser(key, minValue, isFiltered).apply(s);
+        }
+
+        public boolean equals(Object obj) {
+            if (this == obj) return true;
+            if (obj == null || getClass() != obj.getClass()) return false;
+            MinTimeValueParser that = (MinTimeValueParser) obj;
+            return Objects.equals(key, that.key) && Objects.equals(minValue, that.minValue) && Objects.equals(isFiltered, that.isFiltered);
+        }
+
+        public int hashCode() {
+            return Objects.hash(key, minValue, isFiltered);
+        }
+    }
+
     public static Setting<TimeValue> timeSetting(
         final String key,
         Function<Settings, TimeValue> defaultValue,
@@ -2083,7 +2550,7 @@ public static Setting<TimeValue> timeSetting(
         return new Setting<>(
             simpleKey,
             s -> defaultValue.apply(s).getStringRep(),
-            minTimeValueParser(key, minValue, isFiltered(properties)),
+            new MinTimeValueParser(key, minValue, isFiltered(properties)),
             properties
         );
     }
@@ -2099,11 +2566,79 @@ public static Setting<TimeValue> timeSetting(
         return new Setting<>(
             simpleKey,
             s -> defaultValue.getStringRep(),
-            minMaxTimeValueParser(key, minValue, maxValue, isFiltered(properties)),
+            new MinMaxTimeValueParser(key, minValue, maxValue, isFiltered(properties)),
             properties
         );
     }
 
+    /**
+     * A writeable parser for time value have min and max value
+     *
+     */
+    public static class MinMaxTimeValueParser implements Function<String, TimeValue>, Writeable {
+        private String key;
+        private TimeValue minValue;
+        private TimeValue maxValue;
+        private boolean isFiltered;
+
+        public MinMaxTimeValueParser(String key, TimeValue minValue, TimeValue maxValue, boolean isFiltered) {
+            this.key = key;
+            this.minValue = minValue;
+            this.maxValue = maxValue;
+            this.isFiltered = isFiltered;
+        }
+
+        public MinMaxTimeValueParser(StreamInput in) throws IOException {
+            key = in.readString();
+            minValue = in.readTimeValue();
+            maxValue = in.readTimeValue();
+            isFiltered = in.readBoolean();
+        }
+
+        @Override
+        public void writeTo(StreamOutput out) throws IOException {
+            out.writeString(key);
+            out.writeTimeValue(minValue);
+            out.writeTimeValue(maxValue);
+            out.writeBoolean(isFiltered);
+        }
+
+        public TimeValue getMin() {
+            return minValue;
+        }
+
+        public TimeValue getMax() {
+            return maxValue;
+        }
+
+        public String getKey() {
+            return key;
+        }
+
+        public boolean getFilterStatus() {
+            return isFiltered;
+        }
+
+        @Override
+        public TimeValue apply(String s) {
+            return minMaxTimeValueParser(key, minValue, maxValue, isFiltered).apply(s);
+        }
+
+        public boolean equals(Object obj) {
+            if (this == obj) return true;
+            if (obj == null || getClass() != obj.getClass()) return false;
+            MinMaxTimeValueParser that = (MinMaxTimeValueParser) obj;
+            return Objects.equals(key, that.key)
+                && Objects.equals(minValue, that.minValue)
+                && Objects.equals(maxValue, that.maxValue)
+                && Objects.equals(isFiltered, that.isFiltered);
+        }
+
+        public int hashCode() {
+            return Objects.hash(key, minValue, maxValue, isFiltered);
+        }
+    }
+
     private static Function<String, TimeValue> minTimeValueParser(final String key, final TimeValue minValue, boolean isFiltered) {
         return s -> {
             TimeValue value;
diff --git a/server/src/main/java/org/opensearch/common/settings/WriteableSetting.java b/server/src/main/java/org/opensearch/common/settings/WriteableSetting.java
index 2dd0d85ab0cd7..1225202612129 100644
--- a/server/src/main/java/org/opensearch/common/settings/WriteableSetting.java
+++ b/server/src/main/java/org/opensearch/common/settings/WriteableSetting.java
@@ -9,10 +9,20 @@
 package org.opensearch.common.settings;
 
 import org.opensearch.Version;
+import org.opensearch.common.Nullable;
 import org.opensearch.common.io.stream.StreamInput;
 import org.opensearch.common.io.stream.StreamOutput;
 import org.opensearch.common.io.stream.Writeable;
+import org.opensearch.common.settings.Setting.ByteSizeValueParser;
+import org.opensearch.common.settings.Setting.DoubleParser;
+import org.opensearch.common.settings.Setting.FloatParser;
+import org.opensearch.common.settings.Setting.IntegerParser;
+import org.opensearch.common.settings.Setting.LongParser;
+import org.opensearch.common.settings.Setting.MemorySizeValueParser;
+import org.opensearch.common.settings.Setting.MinMaxTimeValueParser;
+import org.opensearch.common.settings.Setting.MinTimeValueParser;
 import org.opensearch.common.settings.Setting.Property;
+import org.opensearch.common.settings.Setting.RegexValidator;
 import org.opensearch.common.unit.ByteSizeValue;
 import org.opensearch.common.unit.TimeValue;
 import java.io.IOException;
@@ -85,12 +95,22 @@ public WriteableSetting(StreamInput in) throws IOException {
         if (hasFallback) {
             fallback = new WriteableSetting(in);
         }
-        // We are using known types so don't need the parser
-        // We are not using validator
+        // Read the parser
+        Object parser = null;
+        boolean isParserWriteable = in.readBoolean();
+        if (isParserWriteable) {
+            parser = readParser(in, parser);
+        }
+        // Read the Validator
+        Object validator = new Object();
+        boolean isValidatorWriteable = in.readBoolean();
+        if (isValidatorWriteable) {
+            validator = readValidator(in);
+        }
         // Read properties
         EnumSet<Property> propSet = in.readEnumSet(Property.class);
         // Put it all in a setting object
-        this.setting = createSetting(type, key, defaultValue, fallback, propSet.toArray(Property[]::new));
+        this.setting = createSetting(type, key, defaultValue, parser, validator, fallback, propSet.toArray(Property[]::new));
     }
 
     /**
@@ -138,6 +158,8 @@ private Setting<?> createSetting(
         SettingType type,
         String key,
         Object defaultValue,
+        @Nullable Object parser,
+        Object validator,
         WriteableSetting fallback,
         Property[] propertyArray
     ) {
@@ -147,33 +169,96 @@ private Setting<?> createSetting(
                     ? Setting.boolSetting(key, (boolean) defaultValue, propertyArray)
                     : Setting.boolSetting(key, (Setting<Boolean>) fallback.getSetting(), propertyArray);
             case Integer:
-                return fallback == null
-                    ? Setting.intSetting(key, (int) defaultValue, propertyArray)
-                    : Setting.intSetting(key, (Setting<Integer>) fallback.getSetting(), propertyArray);
+                if (fallback == null && parser instanceof Writeable) {
+                    return Setting.intSetting(
+                        key,
+                        (int) defaultValue,
+                        ((IntegerParser) parser).getMin(),
+                        ((IntegerParser) parser).getMax(),
+                        propertyArray
+                    );
+                } else if (fallback == null) {
+                    return Setting.intSetting(key, (int) defaultValue, propertyArray);
+                }
+                return Setting.intSetting(key, (Setting<Integer>) fallback.getSetting(), propertyArray);
             case Long:
-                return fallback == null
-                    ? Setting.longSetting(key, (long) defaultValue, propertyArray)
-                    : Setting.longSetting(key, (Setting<Long>) fallback.getSetting(), propertyArray);
+                if (fallback == null && parser instanceof Writeable) {
+                    return Setting.longSetting(
+                        key,
+                        (long) defaultValue,
+                        ((LongParser) parser).getMin(),
+                        ((LongParser) parser).getMax(),
+                        propertyArray
+                    );
+                } else if (fallback == null) {
+                    return Setting.longSetting(key, (long) defaultValue, propertyArray);
+                }
+                return Setting.longSetting(key, (Setting<Long>) fallback.getSetting(), propertyArray);
             case Float:
-                return fallback == null
-                    ? Setting.floatSetting(key, (float) defaultValue, propertyArray)
-                    : Setting.floatSetting(key, (Setting<Float>) fallback.getSetting(), propertyArray);
+                if (fallback == null && parser instanceof Writeable) {
+                    return Setting.floatSetting(
+                        key,
+                        (float) defaultValue,
+                        ((FloatParser) parser).getMin(),
+                        ((FloatParser) parser).getMax(),
+                        propertyArray
+                    );
+                } else if (fallback == null) {
+                    return Setting.floatSetting(key, (float) defaultValue, propertyArray);
+                }
+                return Setting.floatSetting(key, (Setting<Float>) fallback.getSetting(), propertyArray);
             case Double:
-                return fallback == null
-                    ? Setting.doubleSetting(key, (double) defaultValue, propertyArray)
-                    : Setting.doubleSetting(key, (Setting<Double>) fallback.getSetting(), propertyArray);
+                if (fallback == null && parser instanceof Writeable) {
+                    return Setting.doubleSetting(
+                        key,
+                        (double) defaultValue,
+                        ((DoubleParser) parser).getMin(),
+                        ((DoubleParser) parser).getMax(),
+                        propertyArray
+                    );
+                } else if (fallback == null) {
+                    return Setting.doubleSetting(key, (double) defaultValue, propertyArray);
+                }
+                return Setting.doubleSetting(key, (Setting<Double>) fallback.getSetting(), propertyArray);
             case String:
                 return fallback == null
                     ? Setting.simpleString(key, (String) defaultValue, propertyArray)
                     : Setting.simpleString(key, (Setting<String>) fallback.getSetting(), propertyArray);
             case TimeValue:
-                return fallback == null
-                    ? Setting.timeSetting(key, (TimeValue) defaultValue, propertyArray)
-                    : Setting.timeSetting(key, (Setting<TimeValue>) fallback.getSetting(), propertyArray);
+                if (fallback == null && parser instanceof Writeable) {
+                    if (parser instanceof MinMaxTimeValueParser) {
+                        return Setting.timeSetting(
+                            key,
+                            (TimeValue) defaultValue,
+                            ((MinMaxTimeValueParser) parser).getMin(),
+                            ((MinMaxTimeValueParser) parser).getMax(),
+                            propertyArray
+                        );
+                    } else {
+                        return Setting.timeSetting(key, (TimeValue) defaultValue, ((MinTimeValueParser) parser).getMin(), propertyArray);
+                    }
+                } else if (fallback == null) {
+                    return Setting.timeSetting(key, (TimeValue) defaultValue, propertyArray);
+                }
+                return Setting.timeSetting(key, (Setting<TimeValue>) fallback.getSetting(), propertyArray);
             case ByteSizeValue:
-                return fallback == null
-                    ? Setting.byteSizeSetting(key, (ByteSizeValue) defaultValue, propertyArray)
-                    : Setting.byteSizeSetting(key, (Setting<ByteSizeValue>) fallback.getSetting(), propertyArray);
+                if (fallback == null && parser instanceof Writeable) {
+                    if (parser instanceof MemorySizeValueParser) {
+                        return Setting.memorySizeSetting(key, (ByteSizeValue) defaultValue, propertyArray);
+                    } else {
+                        ByteSizeValueParser byteSizeValueParser = (ByteSizeValueParser) parser;
+                        return Setting.byteSizeSetting(
+                            key,
+                            (ByteSizeValue) defaultValue,
+                            byteSizeValueParser.getMin(),
+                            byteSizeValueParser.getMax(),
+                            propertyArray
+                        );
+                    }
+                } else if (fallback == null) {
+                    return Setting.byteSizeSetting(key, (ByteSizeValue) defaultValue, propertyArray);
+                }
+                return Setting.byteSizeSetting(key, (Setting<ByteSizeValue>) fallback.getSetting(), propertyArray);
             case Version:
                 // No fallback option on this method
                 return Setting.versionSetting(key, (Version) defaultValue, propertyArray);
@@ -197,12 +282,63 @@ public void writeTo(StreamOutput out) throws IOException {
         if (hasFallback) {
             new WriteableSetting(setting.fallbackSetting, type).writeTo(out);
         }
-        // We are using known types so don't need the parser
-        // We are not using validator
+        // Write a boolean specifying whether the parser is an instanceof writeable
+        boolean isParserWriteable = setting.parser instanceof Writeable;
+        out.writeBoolean(isParserWriteable);
+        if (isParserWriteable) {
+            writeParser(out, setting.parser);
+        }
+        // Write the validator
+        boolean isValidatorWriteable = setting.validator instanceof Writeable;
+        out.writeBoolean(isValidatorWriteable);
+        if (isValidatorWriteable) {
+            writeValidator(out, setting.validator);
+        }
         // Write properties
         out.writeEnumSet(setting.getProperties());
     }
 
+    private void writeParser(StreamOutput out, Object parser) throws IOException {
+        switch (type) {
+            case Integer:
+                ((IntegerParser) parser).writeTo(out);
+                break;
+            case Long:
+                ((LongParser) parser).writeTo(out);
+                break;
+            case Float:
+                ((FloatParser) parser).writeTo(out);
+                break;
+            case Double:
+                ((DoubleParser) parser).writeTo(out);
+                break;
+            case TimeValue:
+                if (parser instanceof MinMaxTimeValueParser) {
+                    out.writeBoolean(true);
+                    ((MinMaxTimeValueParser) parser).writeTo(out);
+                } else if (parser instanceof MinTimeValueParser) {
+                    out.writeBoolean(false);
+                    ((MinTimeValueParser) parser).writeTo(out);
+                }
+                break;
+            case ByteSizeValue:
+                if (parser instanceof ByteSizeValueParser) {
+                    out.writeBoolean(true);
+                    ((ByteSizeValueParser) parser).writeTo(out);
+                } else if (parser instanceof MemorySizeValueParser) {
+                    out.writeBoolean(false);
+                    ((MemorySizeValueParser) parser).writeTo(out);
+                }
+                break;
+            default:
+                throw new IllegalArgumentException("A SettingType has been added to the enum and not handled here.");
+        }
+    }
+
+    private void writeValidator(StreamOutput out, Object validator) throws IOException {
+        ((Writeable) validator).writeTo(out);
+    }
+
     private void writeDefaultValue(StreamOutput out, Object defaultValue) throws IOException {
         switch (type) {
             case Boolean:
@@ -240,6 +376,37 @@ private void writeDefaultValue(StreamOutput out, Object defaultValue) throws IOE
         }
     }
 
+    private Object readParser(StreamInput in, Object parser) throws IOException {
+        switch (type) {
+            case Integer:
+                return new IntegerParser(in);
+            case Long:
+                return new LongParser(in);
+            case Float:
+                return new FloatParser(in);
+            case Double:
+                return new DoubleParser(in);
+            case TimeValue:
+                if (in.readBoolean()) {
+                    return new MinMaxTimeValueParser(in);
+                } else {
+                    return new MinTimeValueParser(in);
+                }
+            case ByteSizeValue:
+                if (in.readBoolean()) {
+                    return new ByteSizeValueParser(in);
+                } else {
+                    return new MemorySizeValueParser(in);
+                }
+            default:
+                throw new IllegalArgumentException("A SettingType has been added to the enum and not handled here.");
+        }
+    }
+
+    private Object readValidator(StreamInput in) throws IOException {
+        return new RegexValidator(in);
+    }
+
     private Object readDefaultValue(StreamInput in) throws IOException {
         switch (type) {
             case Boolean:
diff --git a/server/src/main/java/org/opensearch/common/unit/Fuzziness.java b/server/src/main/java/org/opensearch/common/unit/Fuzziness.java
index 28947b3936843..813f7e2a43c0f 100644
--- a/server/src/main/java/org/opensearch/common/unit/Fuzziness.java
+++ b/server/src/main/java/org/opensearch/common/unit/Fuzziness.java
@@ -189,7 +189,13 @@ public static Fuzziness parse(XContentParser parser) throws IOException {
                             return build(fuzziness);
                     }
                 } catch (NumberFormatException ex) {
-                    return build(fuzziness);
+                    // Validate if the fuzziness value is formatted correctly as a numeric value.
+                    try {
+                        final float minimumSimilarity = Float.parseFloat(fuzziness);
+                        return build(fuzziness);
+                    } catch (NumberFormatException e) {
+                        throw new IllegalArgumentException("Invalid fuzziness value: " + fuzziness);
+                    }
                 }
 
             default:
@@ -225,7 +231,7 @@ public float asFloat() {
         if (this.equals(AUTO) || isAutoWithCustomValues()) {
             return 1f;
         }
-        return Float.parseFloat(fuzziness.toString());
+        return Float.parseFloat(fuzziness);
     }
 
     private int termLen(String text) {
@@ -234,9 +240,9 @@ private int termLen(String text) {
 
     public String asString() {
         if (isAutoWithCustomValues()) {
-            return fuzziness.toString() + ":" + lowDistance + "," + highDistance;
+            return fuzziness + ":" + lowDistance + "," + highDistance;
         }
-        return fuzziness.toString();
+        return fuzziness;
     }
 
     private boolean isAutoWithCustomValues() {
diff --git a/server/src/main/java/org/opensearch/discovery/InitializeExtensionResponse.java b/server/src/main/java/org/opensearch/discovery/InitializeExtensionResponse.java
index 3be97816dc541..1fc0ee7dd325c 100644
--- a/server/src/main/java/org/opensearch/discovery/InitializeExtensionResponse.java
+++ b/server/src/main/java/org/opensearch/discovery/InitializeExtensionResponse.java
@@ -37,7 +37,9 @@
 import org.opensearch.transport.TransportResponse;
 
 import java.io.IOException;
+import java.util.Arrays;
 import java.util.Objects;
+import java.util.List;
 
 /**
  * PluginResponse to intialize plugin
@@ -46,18 +48,22 @@
  */
 public class InitializeExtensionResponse extends TransportResponse {
     private String name;
+    private List<String> implementedInterfaces;
 
-    public InitializeExtensionResponse(String name) {
+    public InitializeExtensionResponse(String name, List<String> implementedInterfaces) {
         this.name = name;
+        this.implementedInterfaces = implementedInterfaces;
     }
 
     public InitializeExtensionResponse(StreamInput in) throws IOException {
         name = in.readString();
+        this.implementedInterfaces = Arrays.asList(in.readStringArray());
     }
 
     @Override
     public void writeTo(StreamOutput out) throws IOException {
         out.writeString(name);
+        out.writeStringArray(implementedInterfaces.toArray(new String[0]));
     }
 
     /**
@@ -68,9 +74,17 @@ public String getName() {
         return this.name;
     }
 
+    /**
+     * @return interfaces implemented by an extension
+     */
+
+    public List<String> getImplementedInterfaces() {
+        return implementedInterfaces;
+    }
+
     @Override
     public String toString() {
-        return "PluginResponse{" + "name" + name + "}";
+        return "InitializeExtensionResponse{" + "name = " + name + " , " + "implementedInterfaces = " + implementedInterfaces + "}";
     }
 
     @Override
@@ -78,11 +92,11 @@ public boolean equals(Object o) {
         if (this == o) return true;
         if (o == null || getClass() != o.getClass()) return false;
         InitializeExtensionResponse that = (InitializeExtensionResponse) o;
-        return Objects.equals(name, that.name);
+        return Objects.equals(name, that.name) && Objects.equals(implementedInterfaces, that.implementedInterfaces);
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(name);
+        return Objects.hash(name, implementedInterfaces);
     }
 }
diff --git a/server/src/main/java/org/opensearch/env/NodeEnvironment.java b/server/src/main/java/org/opensearch/env/NodeEnvironment.java
index 679d0ef3d7cff..75f855cb330ab 100644
--- a/server/src/main/java/org/opensearch/env/NodeEnvironment.java
+++ b/server/src/main/java/org/opensearch/env/NodeEnvironment.java
@@ -410,7 +410,7 @@ public NodeEnvironment(Settings settings, Environment environment) throws IOExce
      * If the user doesn't configure the cache size, it fails if the node is a data + search node.
      * Else it configures the size to 80% of available capacity for a dedicated search node, if not explicitly defined.
      */
-    private void initializeFileCache(Settings settings) {
+    private void initializeFileCache(Settings settings) throws IOException {
         if (DiscoveryNode.isSearchNode(settings)) {
             long capacity = NODE_SEARCH_CACHE_SIZE_SETTING.get(settings).getBytes();
             FsInfo.Path info = ExceptionsHelper.catchAsRuntimeException(() -> FsProbe.getFSInfo(this.fileCacheNodePath));
@@ -435,6 +435,8 @@ private void initializeFileCache(Settings settings) {
             capacity = Math.min(capacity, availableCapacity);
             fileCacheNodePath.fileCacheReservedSize = new ByteSizeValue(capacity, ByteSizeUnit.BYTES);
             this.fileCache = FileCacheFactory.createConcurrentLRUFileCache(capacity);
+            List<Path> fileCacheDataPaths = collectFileCacheDataPath(this.fileCacheNodePath);
+            this.fileCache.restoreFromDirectory(fileCacheDataPaths);
         }
     }
 
@@ -1305,7 +1307,9 @@ static List<Path> collectFileCacheDataPath(NodePath fileCacheNodePath) throws IO
                             for (Path indexPath : indexStream) {
                                 if (Files.isDirectory(indexPath)) {
                                     try (Stream<Path> shardStream = Files.list(indexPath)) {
-                                        shardStream.map(Path::toAbsolutePath).forEach(indexSubPaths::add);
+                                        shardStream.filter(NodeEnvironment::isShardPath)
+                                            .map(Path::toAbsolutePath)
+                                            .forEach(indexSubPaths::add);
                                     }
                                 }
                             }
@@ -1346,6 +1350,18 @@ private static Path resolveIndexCustomLocation(String customDataPath, String ind
         return resolveBaseCustomLocation(customDataPath, sharedDataPath, nodeLockId).resolve(indexUUID);
     }
 
+    /**
+     * Resolve the file cache path for remote shards.
+     *
+     * @param fileCachePath the file cache path
+     * @param shardId shard to resolve the path to
+     */
+    public Path resolveFileCacheLocation(final Path fileCachePath, final ShardId shardId) {
+        return fileCachePath.resolve(Integer.toString(nodeLockId))
+            .resolve(shardId.getIndex().getUUID())
+            .resolve(Integer.toString(shardId.id()));
+    }
+
     /**
      * Resolve the custom path for a index's shard.
      * Uses the {@code IndexMetadata.SETTING_DATA_PATH} setting to determine
diff --git a/server/src/main/java/org/opensearch/env/NodeRepurposeCommand.java b/server/src/main/java/org/opensearch/env/NodeRepurposeCommand.java
index 58d6f33292273..35f2eead82159 100644
--- a/server/src/main/java/org/opensearch/env/NodeRepurposeCommand.java
+++ b/server/src/main/java/org/opensearch/env/NodeRepurposeCommand.java
@@ -49,6 +49,7 @@
 
 import java.io.IOException;
 import java.nio.file.Path;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
@@ -57,6 +58,7 @@
 import java.util.stream.Stream;
 import java.util.stream.StreamSupport;
 
+import static org.opensearch.env.NodeEnvironment.CACHE_FOLDER;
 import static org.opensearch.env.NodeEnvironment.INDICES_FOLDER;
 
 /**
@@ -68,12 +70,14 @@ public class NodeRepurposeCommand extends OpenSearchNodeCommand {
 
     static final String ABORTED_BY_USER_MSG = OpenSearchNodeCommand.ABORTED_BY_USER_MSG;
     static final String FAILED_TO_OBTAIN_NODE_LOCK_MSG = OpenSearchNodeCommand.FAILED_TO_OBTAIN_NODE_LOCK_MSG;
-    static final String NO_CLEANUP = "Node has node.data=true -> no clean up necessary";
+    static final String NO_CLEANUP = "Node has node.data=true and node.search=true -> no clean up necessary";
     static final String NO_DATA_TO_CLEAN_UP_FOUND = "No data to clean-up found";
     static final String NO_SHARD_DATA_TO_CLEAN_UP_FOUND = "No shard data to clean-up found";
+    static final String NO_FILE_CACHE_DATA_TO_CLEAN_UP_FOUND = "No file cache to clean-up found";
+    private static final int FILE_CACHE_NODE_PATH_LOCATION = 0;
 
     public NodeRepurposeCommand() {
-        super("Repurpose this node to another cluster-manager/data role, cleaning up any excess persisted data");
+        super("Repurpose this node to another cluster-manager/data/search role, cleaning up any excess persisted data");
     }
 
     void testExecute(Terminal terminal, OptionSet options, Environment env) throws Exception {
@@ -83,7 +87,7 @@ void testExecute(Terminal terminal, OptionSet options, Environment env) throws E
     @Override
     protected boolean validateBeforeLock(Terminal terminal, Environment env) {
         Settings settings = env.settings();
-        if (DiscoveryNode.isDataNode(settings)) {
+        if (DiscoveryNode.isDataNode(settings) && DiscoveryNode.isSearchNode(settings)) {
             terminal.println(Terminal.Verbosity.NORMAL, NO_CLEANUP);
             return false;
         }
@@ -94,85 +98,186 @@ protected boolean validateBeforeLock(Terminal terminal, Environment env) {
     @Override
     protected void processNodePaths(Terminal terminal, Path[] dataPaths, int nodeLockId, OptionSet options, Environment env)
         throws IOException {
-        assert DiscoveryNode.isDataNode(env.settings()) == false;
+        assert DiscoveryNode.isDataNode(env.settings()) == false || DiscoveryNode.isSearchNode(env.settings()) == false;
+
+        boolean repurposeData = DiscoveryNode.isDataNode(env.settings()) == false;
+        boolean repurposeSearch = DiscoveryNode.isSearchNode(env.settings()) == false;
 
         if (DiscoveryNode.isClusterManagerNode(env.settings()) == false) {
-            processNoClusterManagerNoDataNode(terminal, dataPaths, env);
+            processNoClusterManagerRepurposeNode(terminal, dataPaths, env, repurposeData, repurposeSearch);
         } else {
-            processClusterManagerNoDataNode(terminal, dataPaths, env);
+            processClusterManagerRepurposeNode(terminal, dataPaths, env, repurposeData, repurposeSearch);
         }
     }
 
-    private void processNoClusterManagerNoDataNode(Terminal terminal, Path[] dataPaths, Environment env) throws IOException {
+    private void processNoClusterManagerRepurposeNode(
+        Terminal terminal,
+        Path[] dataPaths,
+        Environment env,
+        boolean repurposeData,
+        boolean repurposeSearch
+    ) throws IOException {
         NodeEnvironment.NodePath[] nodePaths = toNodePaths(dataPaths);
+        NodeEnvironment.NodePath fileCacheNodePath = toNodePaths(dataPaths)[FILE_CACHE_NODE_PATH_LOCATION];
+        final PersistedClusterStateService persistedClusterStateService = createPersistedClusterStateService(env.settings(), dataPaths);
+        final Metadata metadata = loadClusterState(terminal, env, persistedClusterStateService).metadata();
 
-        terminal.println(Terminal.Verbosity.VERBOSE, "Collecting shard data paths");
-        List<Path> shardDataPaths = NodeEnvironment.collectShardDataPaths(nodePaths);
+        Set<Path> indexPaths = Set.of();
+        List<Path> shardDataPaths = List.of();
+        Set<Path> fileCachePaths = Set.of();
+        List<Path> fileCacheDataPaths = List.of();
 
         terminal.println(Terminal.Verbosity.VERBOSE, "Collecting index metadata paths");
         List<Path> indexMetadataPaths = NodeEnvironment.collectIndexMetadataPaths(nodePaths);
 
-        Set<Path> indexPaths = uniqueParentPaths(shardDataPaths, indexMetadataPaths);
+        if (repurposeData) {
+            terminal.println(Terminal.Verbosity.VERBOSE, "Collecting shard data paths");
+            shardDataPaths = NodeEnvironment.collectShardDataPaths(nodePaths);
+            indexPaths = uniqueParentPaths(shardDataPaths, indexMetadataPaths);
+        }
 
-        final PersistedClusterStateService persistedClusterStateService = createPersistedClusterStateService(env.settings(), dataPaths);
+        if (repurposeSearch) {
+            terminal.println(Terminal.Verbosity.VERBOSE, "Collecting file cache data paths");
+            fileCacheDataPaths = NodeEnvironment.collectFileCacheDataPath(fileCacheNodePath);
+            fileCachePaths = uniqueParentPaths(fileCacheDataPaths, indexMetadataPaths);
+        }
 
-        final Metadata metadata = loadClusterState(terminal, env, persistedClusterStateService).metadata();
-        if (indexPaths.isEmpty() && metadata.indices().isEmpty()) {
+        if (repurposeData && repurposeSearch && fileCacheDataPaths.isEmpty() && indexPaths.isEmpty() && metadata.indices().isEmpty()) {
             terminal.println(Terminal.Verbosity.NORMAL, NO_DATA_TO_CLEAN_UP_FOUND);
             return;
+        } else if (repurposeData && !repurposeSearch && indexPaths.isEmpty() && metadata.indices().isEmpty()) {
+            terminal.println(Terminal.Verbosity.NORMAL, NO_DATA_TO_CLEAN_UP_FOUND);
+            return;
+        } else if (!repurposeData && repurposeSearch && fileCacheDataPaths.isEmpty() && metadata.indices().isEmpty()) {
+            terminal.println(NO_FILE_CACHE_DATA_TO_CLEAN_UP_FOUND);
+            return;
         }
 
         final Set<String> indexUUIDs = Sets.union(
-            indexUUIDsFor(indexPaths),
-            StreamSupport.stream(metadata.indices().values().spliterator(), false)
-                .map(imd -> imd.value.getIndexUUID())
-                .collect(Collectors.toSet())
+            indexUUIDsFor(fileCachePaths),
+            Sets.union(
+                indexUUIDsFor(indexPaths),
+                StreamSupport.stream(metadata.indices().values().spliterator(), false)
+                    .map(imd -> imd.value.getIndexUUID())
+                    .collect(Collectors.toSet())
+            )
         );
 
-        outputVerboseInformation(terminal, indexPaths, indexUUIDs, metadata);
-
-        terminal.println(noClusterManagerMessage(indexUUIDs.size(), shardDataPaths.size(), indexMetadataPaths.size()));
+        List<Path> cleanUpPaths = new ArrayList<>(shardDataPaths);
+        cleanUpPaths.addAll(fileCacheDataPaths);
+        outputVerboseInformation(terminal, cleanUpPaths, indexUUIDs, metadata);
+        terminal.println(noClusterManagerMessage(indexUUIDs.size(), cleanUpPaths.size(), indexMetadataPaths.size()));
         outputHowToSeeVerboseInformation(terminal);
 
-        terminal.println("Node is being re-purposed as no-cluster-manager and no-data. Clean-up of index data will be performed.");
+        if (repurposeData && repurposeSearch) {
+            terminal.println(
+                "Node is being re-purposed as no-cluster-manager, no-data and no-search. Clean-up of index data and file cache will be performed."
+            );
+        } else if (repurposeData) {
+            terminal.println("Node is being re-purposed as no-cluster-manager and no-data. Clean-up of index data will be performed.");
+        } else if (repurposeSearch) {
+            terminal.println(
+                "Node is being re-purposed as no-cluster-manager and no-search. Clean-up of file cache and corresponding index metadata will be performed."
+            );
+        }
         confirm(terminal, "Do you want to proceed?");
 
-        removePaths(terminal, indexPaths); // clean-up shard dirs
         // clean-up all metadata dirs
         MetadataStateFormat.deleteMetaState(dataPaths);
-        IOUtils.rm(Stream.of(dataPaths).map(path -> path.resolve(INDICES_FOLDER)).toArray(Path[]::new));
+        if (repurposeData) {
+            removePaths(terminal, indexPaths); // clean-up shard dirs
+            IOUtils.rm(Stream.of(dataPaths).map(path -> path.resolve(INDICES_FOLDER)).toArray(Path[]::new));
+        }
+
+        if (repurposeSearch) {
+            removePaths(terminal, fileCachePaths); // clean-up file cache dirs
+            IOUtils.rm(dataPaths[FILE_CACHE_NODE_PATH_LOCATION].resolve(CACHE_FOLDER));
+        }
 
-        terminal.println("Node successfully repurposed to no-cluster-manager and no-data.");
+        if (repurposeData && repurposeSearch) {
+            terminal.println("Node successfully repurposed to no-cluster-manager, no-data and no-search.");
+        } else if (repurposeData) {
+            terminal.println("Node successfully repurposed to no-cluster-manager and no-data.");
+        } else if (repurposeSearch) {
+            terminal.println("Node successfully repurposed to no-cluster-manager and no-search.");
+        }
     }
 
-    private void processClusterManagerNoDataNode(Terminal terminal, Path[] dataPaths, Environment env) throws IOException {
+    private void processClusterManagerRepurposeNode(
+        Terminal terminal,
+        Path[] dataPaths,
+        Environment env,
+        boolean repurposeData,
+        boolean repurposeSearch
+    ) throws IOException {
         NodeEnvironment.NodePath[] nodePaths = toNodePaths(dataPaths);
+        NodeEnvironment.NodePath fileCacheNodePath = toNodePaths(dataPaths)[FILE_CACHE_NODE_PATH_LOCATION];
+        final PersistedClusterStateService persistedClusterStateService = createPersistedClusterStateService(env.settings(), dataPaths);
+        final Metadata metadata = loadClusterState(terminal, env, persistedClusterStateService).metadata();
 
-        terminal.println(Terminal.Verbosity.VERBOSE, "Collecting shard data paths");
-        List<Path> shardDataPaths = NodeEnvironment.collectShardDataPaths(nodePaths);
-        if (shardDataPaths.isEmpty()) {
-            terminal.println(NO_SHARD_DATA_TO_CLEAN_UP_FOUND);
-            return;
-        }
+        Set<Path> indexPaths = Set.of();
+        List<Path> shardDataPaths = List.of();
+        Set<Path> fileCachePaths = Set.of();
+        List<Path> fileCacheDataPaths = List.of();
 
-        final PersistedClusterStateService persistedClusterStateService = createPersistedClusterStateService(env.settings(), dataPaths);
+        if (repurposeData) {
+            terminal.println(Terminal.Verbosity.VERBOSE, "Collecting shard data paths");
+            shardDataPaths = NodeEnvironment.collectShardDataPaths(nodePaths);
+            indexPaths = uniqueParentPaths(shardDataPaths);
+        }
 
-        final Metadata metadata = loadClusterState(terminal, env, persistedClusterStateService).metadata();
+        if (repurposeSearch) {
+            terminal.println(Terminal.Verbosity.VERBOSE, "Collecting file cache data paths");
+            fileCacheDataPaths = NodeEnvironment.collectFileCacheDataPath(fileCacheNodePath);
+            fileCachePaths = uniqueParentPaths(fileCacheDataPaths);
+        }
 
-        final Set<Path> indexPaths = uniqueParentPaths(shardDataPaths);
-        final Set<String> indexUUIDs = indexUUIDsFor(indexPaths);
+        if (repurposeData && repurposeSearch && shardDataPaths.isEmpty() && fileCacheDataPaths.isEmpty()) {
+            terminal.println(NO_SHARD_DATA_TO_CLEAN_UP_FOUND);
+            return;
+        } else if (repurposeData && !repurposeSearch && shardDataPaths.isEmpty()) {
+            terminal.println(NO_SHARD_DATA_TO_CLEAN_UP_FOUND);
+            return;
+        } else if (!repurposeData && repurposeSearch && fileCacheDataPaths.isEmpty()) {
+            terminal.println(NO_FILE_CACHE_DATA_TO_CLEAN_UP_FOUND);
+            return;
+        }
 
-        outputVerboseInformation(terminal, shardDataPaths, indexUUIDs, metadata);
+        final Set<String> indexUUIDs = Sets.union(indexUUIDsFor(indexPaths), indexUUIDsFor(fileCachePaths));
 
-        terminal.println(shardMessage(shardDataPaths.size(), indexUUIDs.size()));
+        List<Path> cleanUpPaths = new ArrayList<>(shardDataPaths);
+        cleanUpPaths.addAll(fileCacheDataPaths);
+        outputVerboseInformation(terminal, cleanUpPaths, indexUUIDs, metadata);
+        terminal.println(shardMessage(cleanUpPaths.size(), indexUUIDs.size()));
         outputHowToSeeVerboseInformation(terminal);
 
-        terminal.println("Node is being re-purposed as cluster-manager and no-data. Clean-up of shard data will be performed.");
+        if (repurposeData && repurposeSearch) {
+            terminal.println(
+                "Node is being re-purposed as cluster-manager, no-data and no-search. Clean-up of shard data and file cache data will be performed."
+            );
+        } else if (repurposeData) {
+            terminal.println("Node is being re-purposed as cluster-manager and no-data. Clean-up of shard data will be performed.");
+        } else if (repurposeSearch) {
+            terminal.println("Node is being re-purposed as cluster-manager and no-search. Clean-up of file cache data will be performed.");
+        }
+
         confirm(terminal, "Do you want to proceed?");
 
-        removePaths(terminal, shardDataPaths); // clean-up shard dirs
+        if (repurposeData) {
+            removePaths(terminal, shardDataPaths); // clean-up shard dirs
+        }
+
+        if (repurposeSearch) {
+            removePaths(terminal, fileCacheDataPaths); // clean-up file cache dirs
+        }
 
-        terminal.println("Node successfully repurposed to cluster-manager and no-data.");
+        if (repurposeData && repurposeSearch) {
+            terminal.println("Node successfully repurposed to cluster-manager, no-data and no-search.");
+        } else if (repurposeData) {
+            terminal.println("Node successfully repurposed to cluster-manager and no-data.");
+        } else if (repurposeSearch) {
+            terminal.println("Node successfully repurposed to cluster-manager and no-search.");
+        }
     }
 
     private ClusterState loadClusterState(Terminal terminal, Environment env, PersistedClusterStateService psf) throws IOException {
@@ -211,11 +316,17 @@ private Set<String> indexUUIDsFor(Set<Path> indexPaths) {
     }
 
     static String noClusterManagerMessage(int indexes, int shards, int indexMetadata) {
-        return "Found " + indexes + " indices (" + shards + " shards and " + indexMetadata + " index meta data) to clean up";
+        return "Found "
+            + indexes
+            + " indices ("
+            + shards
+            + " shards/file cache folders and "
+            + indexMetadata
+            + " index meta data) to clean up";
     }
 
     static String shardMessage(int shards, int indices) {
-        return "Found " + shards + " shards in " + indices + " indices to clean up";
+        return "Found " + shards + " shards/file cache folders in " + indices + " indices to clean up";
     }
 
     private void removePaths(Terminal terminal, Collection<Path> paths) {
diff --git a/server/src/main/java/org/opensearch/extensions/DiscoveryExtensionNode.java b/server/src/main/java/org/opensearch/extensions/DiscoveryExtensionNode.java
index 7a15be49d86ee..f52e62ef2cbec 100644
--- a/server/src/main/java/org/opensearch/extensions/DiscoveryExtensionNode.java
+++ b/server/src/main/java/org/opensearch/extensions/DiscoveryExtensionNode.java
@@ -34,6 +34,7 @@ public class DiscoveryExtensionNode extends DiscoveryNode implements Writeable,
 
     private Version minimumCompatibleVersion;
     private List<ExtensionDependency> dependencies = Collections.emptyList();
+    private List<String> implementedInterfaces = Collections.emptyList();
 
     public DiscoveryExtensionNode(
         String name,
@@ -84,6 +85,14 @@ public Version getMinimumCompatibleVersion() {
         return minimumCompatibleVersion;
     }
 
+    public List<String> getImplementedInterfaces() {
+        return implementedInterfaces;
+    }
+
+    public void setImplementedInterfaces(List<String> implementedInterfaces) {
+        this.implementedInterfaces = implementedInterfaces;
+    }
+
     public boolean dependenciesContain(ExtensionDependency dependency) {
         for (ExtensionDependency extensiondependency : this.dependencies) {
             if (dependency.getUniqueId().equals(extensiondependency.getUniqueId())
diff --git a/server/src/main/java/org/opensearch/extensions/ExtensionsManager.java b/server/src/main/java/org/opensearch/extensions/ExtensionsManager.java
index 323e0c7acd715..4f852ca944966 100644
--- a/server/src/main/java/org/opensearch/extensions/ExtensionsManager.java
+++ b/server/src/main/java/org/opensearch/extensions/ExtensionsManager.java
@@ -67,7 +67,6 @@
 import org.opensearch.transport.TransportService;
 import org.yaml.snakeyaml.Yaml;
 import org.opensearch.env.EnvironmentSettingsResponse;
-import org.yaml.snakeyaml.constructor.SafeConstructor;
 
 /**
  * The main class for managing Extension communication with the OpenSearch Node.
@@ -366,6 +365,7 @@ public InitializeExtensionResponse read(StreamInput in) throws IOException {
             public void handleResponse(InitializeExtensionResponse response) {
                 for (DiscoveryExtensionNode extension : extensionIdMap.values()) {
                     if (extension.getName().equals(response.getName())) {
+                        extension.setImplementedInterfaces(response.getImplementedInterfaces());
                         extensions.add(extension);
                         logger.info("Initialized extension: " + extension.getName());
                         break;
@@ -558,7 +558,7 @@ public String executor() {
     }
 
     private ExtensionsSettings readFromExtensionsYml(Path filePath) throws IOException {
-        Yaml yaml = new Yaml(new SafeConstructor());
+        Yaml yaml = new Yaml();
         try (InputStream inputStream = Files.newInputStream(filePath)) {
             Map<String, Object> obj = yaml.load(inputStream);
             if (obj == null) {
diff --git a/server/src/main/java/org/opensearch/extensions/RegisterTransportActionsRequest.java b/server/src/main/java/org/opensearch/extensions/RegisterTransportActionsRequest.java
index 47061f94dee83..94b15e2192722 100644
--- a/server/src/main/java/org/opensearch/extensions/RegisterTransportActionsRequest.java
+++ b/server/src/main/java/org/opensearch/extensions/RegisterTransportActionsRequest.java
@@ -8,18 +8,14 @@
 
 package org.opensearch.extensions;
 
-import org.opensearch.action.ActionRequest;
-import org.opensearch.action.ActionResponse;
-import org.opensearch.action.support.TransportAction;
 import org.opensearch.common.io.stream.StreamInput;
 import org.opensearch.common.io.stream.StreamOutput;
 import org.opensearch.transport.TransportRequest;
 
 import java.io.IOException;
-import java.util.HashMap;
-import java.util.Map;
+import java.util.HashSet;
 import java.util.Objects;
-import java.util.Map.Entry;
+import java.util.Set;
 
 /**
  * Request to register extension Transport actions
@@ -27,41 +23,27 @@
  * @opensearch.internal
  */
 public class RegisterTransportActionsRequest extends TransportRequest {
+    // The uniqueId defining the extension which runs this action
     private String uniqueId;
-    private Map<String, Class<? extends TransportAction<? extends ActionRequest, ? extends ActionResponse>>> transportActions;
+    // The action names to register
+    private Set<String> transportActions;
 
-    public RegisterTransportActionsRequest(
-        String uniqueId,
-        Map<String, Class<? extends TransportAction<? extends ActionRequest, ? extends ActionResponse>>> transportActions
-    ) {
+    public RegisterTransportActionsRequest(String uniqueId, Set<String> transportActions) {
         this.uniqueId = uniqueId;
-        this.transportActions = new HashMap<>(transportActions);
+        this.transportActions = transportActions;
     }
 
     public RegisterTransportActionsRequest(StreamInput in) throws IOException {
         super(in);
         this.uniqueId = in.readString();
-        Map<String, Class<? extends TransportAction<? extends ActionRequest, ? extends ActionResponse>>> actions = new HashMap<>();
-        int actionCount = in.readVInt();
-        for (int i = 0; i < actionCount; i++) {
-            try {
-                String actionName = in.readString();
-                @SuppressWarnings("unchecked")
-                Class<? extends TransportAction<? extends ActionRequest, ? extends ActionResponse>> transportAction = (Class<
-                    ? extends TransportAction<? extends ActionRequest, ? extends ActionResponse>>) Class.forName(in.readString());
-                actions.put(actionName, transportAction);
-            } catch (ClassNotFoundException e) {
-                throw new IllegalArgumentException("Could not read transport action");
-            }
-        }
-        this.transportActions = actions;
+        this.transportActions = new HashSet<>(in.readStringList());
     }
 
     public String getUniqueId() {
         return uniqueId;
     }
 
-    public Map<String, Class<? extends TransportAction<? extends ActionRequest, ? extends ActionResponse>>> getTransportActions() {
+    public Set<String> getTransportActions() {
         return transportActions;
     }
 
@@ -69,12 +51,7 @@ public String getUniqueId() {
     public void writeTo(StreamOutput out) throws IOException {
         super.writeTo(out);
         out.writeString(uniqueId);
-        out.writeVInt(this.transportActions.size());
-        for (Entry<String, Class<? extends TransportAction<? extends ActionRequest, ? extends ActionResponse>>> action : transportActions
-            .entrySet()) {
-            out.writeString(action.getKey());
-            out.writeString(action.getValue().getName());
-        }
+        out.writeStringCollection(transportActions);
     }
 
     @Override
diff --git a/server/src/main/java/org/opensearch/extensions/action/ExtensionTransportActionsHandler.java b/server/src/main/java/org/opensearch/extensions/action/ExtensionTransportActionsHandler.java
index f76fe794b2f84..1f2b58c2bd524 100644
--- a/server/src/main/java/org/opensearch/extensions/action/ExtensionTransportActionsHandler.java
+++ b/server/src/main/java/org/opensearch/extensions/action/ExtensionTransportActionsHandler.java
@@ -93,7 +93,7 @@ public TransportResponse handleRegisterTransportActionsRequest(RegisterTransport
         logger.debug("Register Transport Actions request recieved {}", transportActionsRequest);
         DiscoveryExtensionNode extension = extensionIdMap.get(transportActionsRequest.getUniqueId());
         try {
-            for (String action : transportActionsRequest.getTransportActions().keySet()) {
+            for (String action : transportActionsRequest.getTransportActions()) {
                 registerAction(action, extension);
             }
         } catch (Exception e) {
diff --git a/server/src/main/java/org/opensearch/extensions/rest/RestSendToExtensionAction.java b/server/src/main/java/org/opensearch/extensions/rest/RestSendToExtensionAction.java
index 357be3a9fc2fe..247269e2f1f17 100644
--- a/server/src/main/java/org/opensearch/extensions/rest/RestSendToExtensionAction.java
+++ b/server/src/main/java/org/opensearch/extensions/rest/RestSendToExtensionAction.java
@@ -198,10 +198,9 @@ public String executor() {
             restExecuteOnExtensionResponse.getContent()
         );
         // No constructor that includes headers so we roll our own
-        restExecuteOnExtensionResponse.getHeaders()
-            .entrySet()
-            .stream()
-            .forEach(e -> { e.getValue().stream().forEach(v -> restResponse.addHeader(e.getKey(), v)); });
+        restExecuteOnExtensionResponse.getHeaders().entrySet().stream().forEach(e -> {
+            e.getValue().stream().forEach(v -> restResponse.addHeader(e.getKey(), v));
+        });
 
         return channel -> channel.sendResponse(restResponse);
     }
diff --git a/server/src/main/java/org/opensearch/index/IndexModule.java b/server/src/main/java/org/opensearch/index/IndexModule.java
index 57b9a7c52c2d0..69bc5ef8c37c0 100644
--- a/server/src/main/java/org/opensearch/index/IndexModule.java
+++ b/server/src/main/java/org/opensearch/index/IndexModule.java
@@ -635,7 +635,9 @@ public MapperService newIndexMapperService(
             xContentRegistry,
             new SimilarityService(indexSettings, scriptService, similarities),
             mapperRegistry,
-            () -> { throw new UnsupportedOperationException("no index query shard context available"); },
+            () -> {
+                throw new UnsupportedOperationException("no index query shard context available");
+            },
             () -> false,
             scriptService
         );
diff --git a/server/src/main/java/org/opensearch/index/IndexSortConfig.java b/server/src/main/java/org/opensearch/index/IndexSortConfig.java
index 179d79f90cc8c..f73f96df4f9ad 100644
--- a/server/src/main/java/org/opensearch/index/IndexSortConfig.java
+++ b/server/src/main/java/org/opensearch/index/IndexSortConfig.java
@@ -221,10 +221,9 @@ public Sort buildIndexSort(
             }
             IndexFieldData<?> fieldData;
             try {
-                fieldData = fieldDataLookup.apply(
-                    ft,
-                    () -> { throw new UnsupportedOperationException("index sorting not supported on runtime field [" + ft.name() + "]"); }
-                );
+                fieldData = fieldDataLookup.apply(ft, () -> {
+                    throw new UnsupportedOperationException("index sorting not supported on runtime field [" + ft.name() + "]");
+                });
             } catch (Exception e) {
                 throw new IllegalArgumentException("docvalues not found for index sort field:[" + sortSpec.field + "]", e);
             }
diff --git a/server/src/main/java/org/opensearch/index/IndexWarmer.java b/server/src/main/java/org/opensearch/index/IndexWarmer.java
index 4b49a6c92dd9f..b62afe6b6dcfc 100644
--- a/server/src/main/java/org/opensearch/index/IndexWarmer.java
+++ b/server/src/main/java/org/opensearch/index/IndexWarmer.java
@@ -166,7 +166,9 @@ public TerminationHandle warmReader(final IndexShard indexShard, final OpenSearc
                         IndexFieldData.Global<?> ifd = indexFieldDataService.getForField(
                             fieldType,
                             indexFieldDataService.index().getName(),
-                            () -> { throw new UnsupportedOperationException("search lookup not available when warming an index"); }
+                            () -> {
+                                throw new UnsupportedOperationException("search lookup not available when warming an index");
+                            }
                         );
                         IndexFieldData<?> global = ifd.loadGlobal(reader);
                         if (reader.leaves().isEmpty() == false) {
diff --git a/server/src/main/java/org/opensearch/index/SegmentReplicationPerGroupStats.java b/server/src/main/java/org/opensearch/index/SegmentReplicationPerGroupStats.java
new file mode 100644
index 0000000000000..23beef419e7b6
--- /dev/null
+++ b/server/src/main/java/org/opensearch/index/SegmentReplicationPerGroupStats.java
@@ -0,0 +1,78 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.index;
+
+import org.opensearch.common.io.stream.StreamInput;
+import org.opensearch.common.io.stream.StreamOutput;
+import org.opensearch.common.io.stream.Writeable;
+import org.opensearch.common.xcontent.ToXContentFragment;
+import org.opensearch.common.xcontent.XContentBuilder;
+import org.opensearch.index.shard.ShardId;
+
+import java.io.IOException;
+import java.util.Set;
+
+/**
+ * Return Segment Replication stats for a Replication Group.
+ *
+ * @opensearch.internal
+ */
+public class SegmentReplicationPerGroupStats implements Writeable, ToXContentFragment {
+
+    private final ShardId shardId;
+    private final Set<SegmentReplicationShardStats> replicaStats;
+    private final long rejectedRequestCount;
+
+    public SegmentReplicationPerGroupStats(ShardId shardId, Set<SegmentReplicationShardStats> replicaStats, long rejectedRequestCount) {
+        this.shardId = shardId;
+        this.replicaStats = replicaStats;
+        this.rejectedRequestCount = rejectedRequestCount;
+    }
+
+    public SegmentReplicationPerGroupStats(StreamInput in) throws IOException {
+        this.shardId = new ShardId(in);
+        this.replicaStats = in.readSet(SegmentReplicationShardStats::new);
+        this.rejectedRequestCount = in.readVLong();
+    }
+
+    public Set<SegmentReplicationShardStats> getReplicaStats() {
+        return replicaStats;
+    }
+
+    public long getRejectedRequestCount() {
+        return rejectedRequestCount;
+    }
+
+    public ShardId getShardId() {
+        return shardId;
+    }
+
+    @Override
+    public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+        builder.field("rejected_requests", rejectedRequestCount);
+        builder.startArray("replicas");
+        for (SegmentReplicationShardStats stats : replicaStats) {
+            stats.toXContent(builder, params);
+        }
+        builder.endArray();
+        return builder;
+    }
+
+    @Override
+    public void writeTo(StreamOutput out) throws IOException {
+        shardId.writeTo(out);
+        out.writeCollection(replicaStats);
+        out.writeVLong(rejectedRequestCount);
+    }
+
+    @Override
+    public String toString() {
+        return "SegmentReplicationPerGroupStats{" + "replicaStats=" + replicaStats + ", rejectedRequestCount=" + rejectedRequestCount + '}';
+    }
+}
diff --git a/server/src/main/java/org/opensearch/index/SegmentReplicationPressureService.java b/server/src/main/java/org/opensearch/index/SegmentReplicationPressureService.java
new file mode 100644
index 0000000000000..f31e236fb6184
--- /dev/null
+++ b/server/src/main/java/org/opensearch/index/SegmentReplicationPressureService.java
@@ -0,0 +1,157 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.index;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.opensearch.cluster.service.ClusterService;
+import org.opensearch.common.inject.Inject;
+import org.opensearch.common.settings.ClusterSettings;
+import org.opensearch.common.settings.Setting;
+import org.opensearch.common.settings.Settings;
+import org.opensearch.common.unit.TimeValue;
+import org.opensearch.common.util.concurrent.OpenSearchRejectedExecutionException;
+import org.opensearch.index.shard.IndexShard;
+import org.opensearch.index.shard.ShardId;
+import org.opensearch.indices.IndicesService;
+
+import java.util.Set;
+import java.util.stream.Collectors;
+
+/**
+ * Service responsible for applying backpressure for lagging behind replicas when Segment Replication is enabled.
+ *
+ * @opensearch.internal
+ */
+public class SegmentReplicationPressureService {
+
+    private volatile boolean isSegmentReplicationBackpressureEnabled;
+    private volatile int maxCheckpointsBehind;
+    private volatile double maxAllowedStaleReplicas;
+    private volatile TimeValue maxReplicationTime;
+
+    private static final Logger logger = LogManager.getLogger(SegmentReplicationPressureService.class);
+
+    public static final Setting<Boolean> SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED = Setting.boolSetting(
+        "segrep.pressure.enabled",
+        false,
+        Setting.Property.Dynamic,
+        Setting.Property.NodeScope
+    );
+
+    public static final Setting<Integer> MAX_INDEXING_CHECKPOINTS = Setting.intSetting(
+        "segrep.pressure.checkpoint.limit",
+        4,
+        1,
+        Setting.Property.Dynamic,
+        Setting.Property.NodeScope
+    );
+
+    public static final Setting<TimeValue> MAX_REPLICATION_TIME_SETTING = Setting.positiveTimeSetting(
+        "segrep.pressure.time.limit",
+        TimeValue.timeValueMinutes(5),
+        Setting.Property.Dynamic,
+        Setting.Property.NodeScope
+    );
+
+    public static final Setting<Double> MAX_ALLOWED_STALE_SHARDS = Setting.doubleSetting(
+        "segrep.pressure.replica.stale.limit",
+        .5,
+        0,
+        1,
+        Setting.Property.Dynamic,
+        Setting.Property.NodeScope
+    );
+
+    private final IndicesService indicesService;
+    private final SegmentReplicationStatsTracker tracker;
+
+    @Inject
+    public SegmentReplicationPressureService(Settings settings, ClusterService clusterService, IndicesService indicesService) {
+        this.indicesService = indicesService;
+        this.tracker = new SegmentReplicationStatsTracker(this.indicesService);
+
+        final ClusterSettings clusterSettings = clusterService.getClusterSettings();
+        this.isSegmentReplicationBackpressureEnabled = SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED.get(settings);
+        clusterSettings.addSettingsUpdateConsumer(
+            SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED,
+            this::setSegmentReplicationBackpressureEnabled
+        );
+
+        this.maxCheckpointsBehind = MAX_INDEXING_CHECKPOINTS.get(settings);
+        clusterSettings.addSettingsUpdateConsumer(MAX_INDEXING_CHECKPOINTS, this::setMaxCheckpointsBehind);
+
+        this.maxReplicationTime = MAX_REPLICATION_TIME_SETTING.get(settings);
+        clusterSettings.addSettingsUpdateConsumer(MAX_REPLICATION_TIME_SETTING, this::setMaxReplicationTime);
+
+        this.maxAllowedStaleReplicas = MAX_ALLOWED_STALE_SHARDS.get(settings);
+        clusterSettings.addSettingsUpdateConsumer(MAX_ALLOWED_STALE_SHARDS, this::setMaxAllowedStaleReplicas);
+    }
+
+    public void isSegrepLimitBreached(ShardId shardId) {
+        final IndexService indexService = indicesService.indexService(shardId.getIndex());
+        final IndexShard shard = indexService.getShard(shardId.id());
+        if (isSegmentReplicationBackpressureEnabled && shard.indexSettings().isSegRepEnabled() && shard.routingEntry().primary()) {
+            validateReplicationGroup(shard);
+        }
+    }
+
+    private void validateReplicationGroup(IndexShard shard) {
+        final Set<SegmentReplicationShardStats> replicaStats = shard.getReplicationStats();
+        final Set<SegmentReplicationShardStats> staleReplicas = getStaleReplicas(replicaStats);
+        if (staleReplicas.isEmpty() == false) {
+            // inSyncIds always considers the primary id, so filter it out.
+            final float percentStale = staleReplicas.size() * 100f / (shard.getReplicationGroup().getInSyncAllocationIds().size() - 1);
+            final double maxStaleLimit = maxAllowedStaleReplicas * 100f;
+            if (percentStale >= maxStaleLimit) {
+                tracker.incrementRejectionCount(shard.shardId());
+                logger.warn("Rejecting write requests for shard, stale shards [{}%] shards: {}", percentStale, staleReplicas);
+                throw new OpenSearchRejectedExecutionException(
+                    "rejected execution on primary shard: " + shard.shardId() + " Stale Replicas: " + staleReplicas + "]",
+                    false
+                );
+            }
+        }
+    }
+
+    private Set<SegmentReplicationShardStats> getStaleReplicas(final Set<SegmentReplicationShardStats> replicas) {
+        return replicas.stream()
+            .filter(entry -> entry.getCheckpointsBehindCount() > maxCheckpointsBehind)
+            .filter(entry -> entry.getCurrentReplicationTimeMillis() > maxReplicationTime.millis())
+            .collect(Collectors.toSet());
+    }
+
+    public SegmentReplicationStats nodeStats() {
+        return tracker.getStats();
+    }
+
+    public SegmentReplicationPerGroupStats getStatsForShard(IndexShard indexShard) {
+        return tracker.getStatsForShard(indexShard);
+    }
+
+    public boolean isSegmentReplicationBackpressureEnabled() {
+        return isSegmentReplicationBackpressureEnabled;
+    }
+
+    public void setSegmentReplicationBackpressureEnabled(boolean segmentReplicationBackpressureEnabled) {
+        isSegmentReplicationBackpressureEnabled = segmentReplicationBackpressureEnabled;
+    }
+
+    public void setMaxCheckpointsBehind(int maxCheckpointsBehind) {
+        this.maxCheckpointsBehind = maxCheckpointsBehind;
+    }
+
+    public void setMaxAllowedStaleReplicas(double maxAllowedStaleReplicas) {
+        this.maxAllowedStaleReplicas = maxAllowedStaleReplicas;
+    }
+
+    public void setMaxReplicationTime(TimeValue maxReplicationTime) {
+        this.maxReplicationTime = maxReplicationTime;
+    }
+}
diff --git a/server/src/main/java/org/opensearch/index/SegmentReplicationShardStats.java b/server/src/main/java/org/opensearch/index/SegmentReplicationShardStats.java
new file mode 100644
index 0000000000000..b68c49453222b
--- /dev/null
+++ b/server/src/main/java/org/opensearch/index/SegmentReplicationShardStats.java
@@ -0,0 +1,132 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.index;
+
+import org.opensearch.common.Nullable;
+import org.opensearch.common.io.stream.StreamInput;
+import org.opensearch.common.io.stream.StreamOutput;
+import org.opensearch.common.io.stream.Writeable;
+import org.opensearch.common.unit.ByteSizeValue;
+import org.opensearch.common.unit.TimeValue;
+import org.opensearch.common.xcontent.ToXContentFragment;
+import org.opensearch.common.xcontent.XContentBuilder;
+import org.opensearch.indices.replication.SegmentReplicationState;
+
+import java.io.IOException;
+
+/**
+ * SegRep stats for a single shard.
+ *
+ * @opensearch.internal
+ */
+public class SegmentReplicationShardStats implements Writeable, ToXContentFragment {
+    private final String allocationId;
+    private final long checkpointsBehindCount;
+    private final long bytesBehindCount;
+    private final long currentReplicationTimeMillis;
+    private final long lastCompletedReplicationTimeMillis;
+
+    @Nullable
+    private SegmentReplicationState currentReplicationState;
+
+    public SegmentReplicationShardStats(
+        String allocationId,
+        long checkpointsBehindCount,
+        long bytesBehindCount,
+        long currentReplicationTimeMillis,
+        long lastCompletedReplicationTime
+    ) {
+        this.allocationId = allocationId;
+        this.checkpointsBehindCount = checkpointsBehindCount;
+        this.bytesBehindCount = bytesBehindCount;
+        this.currentReplicationTimeMillis = currentReplicationTimeMillis;
+        this.lastCompletedReplicationTimeMillis = lastCompletedReplicationTime;
+    }
+
+    public SegmentReplicationShardStats(StreamInput in) throws IOException {
+        this.allocationId = in.readString();
+        this.checkpointsBehindCount = in.readVLong();
+        this.bytesBehindCount = in.readVLong();
+        this.currentReplicationTimeMillis = in.readVLong();
+        this.lastCompletedReplicationTimeMillis = in.readVLong();
+    }
+
+    public String getAllocationId() {
+        return allocationId;
+    }
+
+    public long getCheckpointsBehindCount() {
+        return checkpointsBehindCount;
+    }
+
+    public long getBytesBehindCount() {
+        return bytesBehindCount;
+    }
+
+    public long getCurrentReplicationTimeMillis() {
+        return currentReplicationTimeMillis;
+    }
+
+    public long getLastCompletedReplicationTimeMillis() {
+        return lastCompletedReplicationTimeMillis;
+    }
+
+    public void setCurrentReplicationState(SegmentReplicationState currentReplicationState) {
+        this.currentReplicationState = currentReplicationState;
+    }
+
+    @Nullable
+    public SegmentReplicationState getCurrentReplicationState() {
+        return currentReplicationState;
+    }
+
+    @Override
+    public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+        builder.startObject();
+        builder.field("allocation_id", allocationId);
+        builder.field("checkpoints_behind", checkpointsBehindCount);
+        builder.field("bytes_behind", new ByteSizeValue(bytesBehindCount).toString());
+        builder.field("current_replication_time", new TimeValue(currentReplicationTimeMillis));
+        builder.field("last_completed_replication_time", new TimeValue(lastCompletedReplicationTimeMillis));
+        if (currentReplicationState != null) {
+            builder.startObject();
+            currentReplicationState.toXContent(builder, params);
+            builder.endObject();
+        }
+        builder.endObject();
+        return builder;
+    }
+
+    @Override
+    public void writeTo(StreamOutput out) throws IOException {
+        out.writeString(allocationId);
+        out.writeVLong(checkpointsBehindCount);
+        out.writeVLong(bytesBehindCount);
+        out.writeVLong(currentReplicationTimeMillis);
+        out.writeVLong(lastCompletedReplicationTimeMillis);
+    }
+
+    @Override
+    public String toString() {
+        return "SegmentReplicationShardStats{"
+            + "allocationId="
+            + allocationId
+            + ", checkpointsBehindCount="
+            + checkpointsBehindCount
+            + ", bytesBehindCount="
+            + bytesBehindCount
+            + ", currentReplicationTimeMillis="
+            + currentReplicationTimeMillis
+            + ", lastCompletedReplicationTimeMillis="
+            + lastCompletedReplicationTimeMillis
+            + ", currentReplicationState="
+            + currentReplicationState
+            + '}';
+    }
+}
diff --git a/server/src/main/java/org/opensearch/index/SegmentReplicationStats.java b/server/src/main/java/org/opensearch/index/SegmentReplicationStats.java
new file mode 100644
index 0000000000000..10975e48443d8
--- /dev/null
+++ b/server/src/main/java/org/opensearch/index/SegmentReplicationStats.java
@@ -0,0 +1,73 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.index;
+
+import org.opensearch.common.io.stream.StreamInput;
+import org.opensearch.common.io.stream.StreamOutput;
+import org.opensearch.common.io.stream.Writeable;
+import org.opensearch.common.xcontent.ToXContentFragment;
+import org.opensearch.common.xcontent.XContentBuilder;
+import org.opensearch.index.shard.ShardId;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Segment Replication Stats.
+ *
+ * @opensearch.internal
+ */
+public class SegmentReplicationStats implements Writeable, ToXContentFragment {
+
+    private final Map<ShardId, SegmentReplicationPerGroupStats> shardStats;
+
+    public SegmentReplicationStats(final Map<ShardId, SegmentReplicationPerGroupStats> shardStats) {
+        this.shardStats = shardStats;
+    }
+
+    public SegmentReplicationStats(StreamInput in) throws IOException {
+        int shardEntries = in.readInt();
+        shardStats = new HashMap<>();
+        for (int i = 0; i < shardEntries; i++) {
+            ShardId shardId = new ShardId(in);
+            SegmentReplicationPerGroupStats groupStats = new SegmentReplicationPerGroupStats(in);
+            shardStats.put(shardId, groupStats);
+        }
+    }
+
+    public Map<ShardId, SegmentReplicationPerGroupStats> getShardStats() {
+        return shardStats;
+    }
+
+    @Override
+    public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+        builder.startObject("segment_replication");
+        for (Map.Entry<ShardId, SegmentReplicationPerGroupStats> entry : shardStats.entrySet()) {
+            builder.startObject(entry.getKey().toString());
+            entry.getValue().toXContent(builder, params);
+            builder.endObject();
+        }
+        return builder.endObject();
+    }
+
+    @Override
+    public void writeTo(StreamOutput out) throws IOException {
+        out.writeInt(shardStats.size());
+        for (Map.Entry<ShardId, SegmentReplicationPerGroupStats> entry : shardStats.entrySet()) {
+            entry.getKey().writeTo(out);
+            entry.getValue().writeTo(out);
+        }
+    }
+
+    @Override
+    public String toString() {
+        return "SegmentReplicationStats{" + "shardStats=" + shardStats + '}';
+    }
+}
diff --git a/server/src/main/java/org/opensearch/index/SegmentReplicationStatsTracker.java b/server/src/main/java/org/opensearch/index/SegmentReplicationStatsTracker.java
new file mode 100644
index 0000000000000..d7176127615d5
--- /dev/null
+++ b/server/src/main/java/org/opensearch/index/SegmentReplicationStatsTracker.java
@@ -0,0 +1,66 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.index;
+
+import org.opensearch.common.util.concurrent.ConcurrentCollections;
+import org.opensearch.index.shard.IndexShard;
+import org.opensearch.index.shard.ShardId;
+import org.opensearch.indices.IndicesService;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Optional;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * Tracker responsible for computing SegmentReplicationStats.
+ *
+ * @opensearch.internal
+ */
+public class SegmentReplicationStatsTracker {
+
+    private final IndicesService indicesService;
+    private final Map<ShardId, AtomicInteger> rejectionCount;
+
+    public SegmentReplicationStatsTracker(IndicesService indicesService) {
+        this.indicesService = indicesService;
+        rejectionCount = ConcurrentCollections.newConcurrentMap();
+    }
+
+    public SegmentReplicationStats getStats() {
+        Map<ShardId, SegmentReplicationPerGroupStats> stats = new HashMap<>();
+        for (IndexService indexService : indicesService) {
+            for (IndexShard indexShard : indexService) {
+                if (indexShard.indexSettings().isSegRepEnabled() && indexShard.routingEntry().primary()) {
+                    stats.putIfAbsent(indexShard.shardId(), getStatsForShard(indexShard));
+                }
+            }
+        }
+        return new SegmentReplicationStats(stats);
+    }
+
+    public void incrementRejectionCount(ShardId shardId) {
+        rejectionCount.compute(shardId, (k, v) -> {
+            if (v == null) {
+                return new AtomicInteger(1);
+            } else {
+                v.incrementAndGet();
+                return v;
+            }
+        });
+    }
+
+    public SegmentReplicationPerGroupStats getStatsForShard(IndexShard indexShard) {
+        return new SegmentReplicationPerGroupStats(
+            indexShard.shardId(),
+            indexShard.getReplicationStats(),
+            Optional.ofNullable(rejectionCount.get(indexShard.shardId())).map(AtomicInteger::get).orElse(0)
+        );
+    }
+}
diff --git a/server/src/main/java/org/opensearch/index/analysis/AnalysisRegistry.java b/server/src/main/java/org/opensearch/index/analysis/AnalysisRegistry.java
index 8ec2b70001fc9..cb686dba1ab0f 100644
--- a/server/src/main/java/org/opensearch/index/analysis/AnalysisRegistry.java
+++ b/server/src/main/java/org/opensearch/index/analysis/AnalysisRegistry.java
@@ -648,7 +648,9 @@ public IndexAnalyzers build(
                     charFilterFactoryFactories,
                     tokenizerFactoryFactories
                 ),
-                (k, v) -> { throw new IllegalStateException("already registered analyzer with name: " + entry.getKey()); }
+                (k, v) -> {
+                    throw new IllegalStateException("already registered analyzer with name: " + entry.getKey());
+                }
             );
         }
         for (Map.Entry<String, AnalyzerProvider<?>> entry : normalizerProviders.entrySet()) {
diff --git a/server/src/main/java/org/opensearch/index/engine/NRTReplicationEngine.java b/server/src/main/java/org/opensearch/index/engine/NRTReplicationEngine.java
index 76461783fb724..8071e94d1426d 100644
--- a/server/src/main/java/org/opensearch/index/engine/NRTReplicationEngine.java
+++ b/server/src/main/java/org/opensearch/index/engine/NRTReplicationEngine.java
@@ -42,6 +42,8 @@
 import java.util.function.BiFunction;
 import java.util.stream.Stream;
 
+import static org.opensearch.index.seqno.SequenceNumbers.MAX_SEQ_NO;
+
 /**
  * This is an {@link Engine} implementation intended for replica shards when Segment Replication
  * is enabled.  This Engine does not create an IndexWriter, rather it refreshes a {@link NRTReplicationReaderManager}
@@ -123,10 +125,11 @@ public TranslogManager translogManager() {
         return translogManager;
     }
 
-    public synchronized void updateSegments(final SegmentInfos infos, long seqNo) throws IOException {
+    public synchronized void updateSegments(final SegmentInfos infos) throws IOException {
         // Update the current infos reference on the Engine's reader.
         ensureOpen();
         try (ReleasableLock lock = writeLock.acquire()) {
+            final long maxSeqNo = Long.parseLong(infos.userData.get(MAX_SEQ_NO));
             final long incomingGeneration = infos.getGeneration();
             readerManager.updateSegments(infos);
 
@@ -134,11 +137,11 @@ public synchronized void updateSegments(final SegmentInfos infos, long seqNo) th
             // lower/higher gens are possible from a new primary that was just elected.
             if (incomingGeneration != lastReceivedGen) {
                 commitSegmentInfos();
-                translogManager.getDeletionPolicy().setLocalCheckpointOfSafeCommit(seqNo);
+                translogManager.getDeletionPolicy().setLocalCheckpointOfSafeCommit(maxSeqNo);
                 translogManager.rollTranslogGeneration();
             }
             lastReceivedGen = incomingGeneration;
-            localCheckpointTracker.fastForwardProcessedSeqNo(seqNo);
+            localCheckpointTracker.fastForwardProcessedSeqNo(maxSeqNo);
         }
     }
 
@@ -343,11 +346,22 @@ public List<Segment> segments(boolean verbose) {
     }
 
     @Override
-    public void refresh(String source) throws EngineException {}
+    public void refresh(String source) throws EngineException {
+        maybeRefresh(source);
+    }
 
     @Override
     public boolean maybeRefresh(String source) throws EngineException {
-        return false;
+        try {
+            return readerManager.maybeRefresh();
+        } catch (IOException e) {
+            try {
+                failEngine("refresh failed source[" + source + "]", e);
+            } catch (Exception inner) {
+                e.addSuppressed(inner);
+            }
+            throw new RefreshFailedEngineException(shardId, e);
+        }
     }
 
     @Override
diff --git a/server/src/main/java/org/opensearch/index/engine/NRTReplicationReaderManager.java b/server/src/main/java/org/opensearch/index/engine/NRTReplicationReaderManager.java
index 8fbb24720aedc..00748acb1d76d 100644
--- a/server/src/main/java/org/opensearch/index/engine/NRTReplicationReaderManager.java
+++ b/server/src/main/java/org/opensearch/index/engine/NRTReplicationReaderManager.java
@@ -51,6 +51,10 @@ public class NRTReplicationReaderManager extends OpenSearchReaderManager {
     @Override
     protected OpenSearchDirectoryReader refreshIfNeeded(OpenSearchDirectoryReader referenceToRefresh) throws IOException {
         Objects.requireNonNull(referenceToRefresh);
+        // checks if an actual refresh (change in segments) happened
+        if (unwrapStandardReader(referenceToRefresh).getSegmentInfos().version == currentInfos.version) {
+            return null;
+        }
         final List<LeafReader> subs = new ArrayList<>();
         final StandardDirectoryReader standardDirectoryReader = unwrapStandardReader(referenceToRefresh);
         for (LeafReaderContext ctx : standardDirectoryReader.leaves()) {
diff --git a/server/src/main/java/org/opensearch/index/mapper/ArraySourceValueFetcher.java b/server/src/main/java/org/opensearch/index/mapper/ArraySourceValueFetcher.java
index 936d6b4fb7f8b..f5dc34ab8ac5d 100644
--- a/server/src/main/java/org/opensearch/index/mapper/ArraySourceValueFetcher.java
+++ b/server/src/main/java/org/opensearch/index/mapper/ArraySourceValueFetcher.java
@@ -74,7 +74,7 @@ public List<Object> fetchValues(SourceLookup lookup) {
         for (String path : sourcePaths) {
             Object sourceValue = lookup.extractValue(path, nullValue);
             if (sourceValue == null) {
-                return org.opensearch.common.collect.List.of();
+                return List.of();
             }
             values.addAll((List<?>) parseSourceValue(sourceValue));
         }
diff --git a/server/src/main/java/org/opensearch/index/mapper/DocumentParser.java b/server/src/main/java/org/opensearch/index/mapper/DocumentParser.java
index a346d57924199..4b2f02ac3828a 100644
--- a/server/src/main/java/org/opensearch/index/mapper/DocumentParser.java
+++ b/server/src/main/java/org/opensearch/index/mapper/DocumentParser.java
@@ -425,34 +425,40 @@ private static void innerParseObject(
         String currentFieldName,
         XContentParser.Token token
     ) throws IOException {
-        assert token == XContentParser.Token.FIELD_NAME || token == XContentParser.Token.END_OBJECT;
-        String[] paths = null;
-        while (token != XContentParser.Token.END_OBJECT) {
-            if (token == XContentParser.Token.FIELD_NAME) {
-                currentFieldName = parser.currentName();
-                paths = splitAndValidatePath(currentFieldName);
-                if (containsDisabledObjectMapper(mapper, paths)) {
-                    parser.nextToken();
-                    parser.skipChildren();
+        try {
+            assert token == XContentParser.Token.FIELD_NAME || token == XContentParser.Token.END_OBJECT;
+            String[] paths = null;
+            context.incrementFieldCurrentDepth();
+            context.checkFieldDepthLimit();
+            while (token != XContentParser.Token.END_OBJECT) {
+                if (token == XContentParser.Token.FIELD_NAME) {
+                    currentFieldName = parser.currentName();
+                    paths = splitAndValidatePath(currentFieldName);
+                    if (containsDisabledObjectMapper(mapper, paths)) {
+                        parser.nextToken();
+                        parser.skipChildren();
+                    }
+                } else if (token == XContentParser.Token.START_OBJECT) {
+                    parseObject(context, mapper, currentFieldName, paths);
+                } else if (token == XContentParser.Token.START_ARRAY) {
+                    parseArray(context, mapper, currentFieldName, paths);
+                } else if (token == XContentParser.Token.VALUE_NULL) {
+                    parseNullValue(context, mapper, currentFieldName, paths);
+                } else if (token == null) {
+                    throw new MapperParsingException(
+                        "object mapping for ["
+                            + mapper.name()
+                            + "] tried to parse field ["
+                            + currentFieldName
+                            + "] as object, but got EOF, has a concrete value been provided to it?"
+                    );
+                } else if (token.isValue()) {
+                    parseValue(context, mapper, currentFieldName, token, paths);
                 }
-            } else if (token == XContentParser.Token.START_OBJECT) {
-                parseObject(context, mapper, currentFieldName, paths);
-            } else if (token == XContentParser.Token.START_ARRAY) {
-                parseArray(context, mapper, currentFieldName, paths);
-            } else if (token == XContentParser.Token.VALUE_NULL) {
-                parseNullValue(context, mapper, currentFieldName, paths);
-            } else if (token == null) {
-                throw new MapperParsingException(
-                    "object mapping for ["
-                        + mapper.name()
-                        + "] tried to parse field ["
-                        + currentFieldName
-                        + "] as object, but got EOF, has a concrete value been provided to it?"
-                );
-            } else if (token.isValue()) {
-                parseValue(context, mapper, currentFieldName, token, paths);
+                token = parser.nextToken();
             }
-            token = parser.nextToken();
+        } finally {
+            context.decrementFieldCurrentDepth();
         }
     }
 
@@ -563,50 +569,59 @@ private static void parseObject(final ParseContext context, ObjectMapper mapper,
 
     private static void parseArray(ParseContext context, ObjectMapper parentMapper, String lastFieldName, String[] paths)
         throws IOException {
-        String arrayFieldName = lastFieldName;
-
-        Mapper mapper = getMapper(context, parentMapper, lastFieldName, paths);
-        if (mapper != null) {
-            // There is a concrete mapper for this field already. Need to check if the mapper
-            // expects an array, if so we pass the context straight to the mapper and if not
-            // we serialize the array components
-            if (parsesArrayValue(mapper)) {
-                parseObjectOrField(context, mapper);
-            } else {
-                parseNonDynamicArray(context, parentMapper, lastFieldName, arrayFieldName);
-            }
-        } else {
-            arrayFieldName = paths[paths.length - 1];
-            lastFieldName = arrayFieldName;
-            Tuple<Integer, ObjectMapper> parentMapperTuple = getDynamicParentMapper(context, paths, parentMapper);
-            parentMapper = parentMapperTuple.v2();
-            ObjectMapper.Dynamic dynamic = dynamicOrDefault(parentMapper, context);
-            if (dynamic == ObjectMapper.Dynamic.STRICT) {
-                throw new StrictDynamicMappingException(parentMapper.fullPath(), arrayFieldName);
-            } else if (dynamic == ObjectMapper.Dynamic.TRUE) {
-                Mapper.Builder builder = context.root().findTemplateBuilder(context, arrayFieldName, XContentFieldType.OBJECT);
-                if (builder == null) {
-                    parseNonDynamicArray(context, parentMapper, lastFieldName, arrayFieldName);
+        try {
+            String arrayFieldName = lastFieldName;
+            context.incrementFieldArrayDepth();
+            context.checkFieldArrayDepthLimit();
+
+            Mapper mapper = getMapper(context, parentMapper, lastFieldName, paths);
+            if (mapper != null) {
+                // There is a concrete mapper for this field already. Need to check if the mapper
+                // expects an array, if so we pass the context straight to the mapper and if not
+                // we serialize the array components
+                if (parsesArrayValue(mapper)) {
+                    parseObjectOrField(context, mapper);
                 } else {
-                    Mapper.BuilderContext builderContext = new Mapper.BuilderContext(context.indexSettings().getSettings(), context.path());
-                    mapper = builder.build(builderContext);
-                    assert mapper != null;
-                    if (parsesArrayValue(mapper)) {
-                        context.addDynamicMapper(mapper);
-                        context.path().add(arrayFieldName);
-                        parseObjectOrField(context, mapper);
-                        context.path().remove();
-                    } else {
+                    parseNonDynamicArray(context, parentMapper, lastFieldName, arrayFieldName);
+                }
+            } else {
+                arrayFieldName = paths[paths.length - 1];
+                lastFieldName = arrayFieldName;
+                Tuple<Integer, ObjectMapper> parentMapperTuple = getDynamicParentMapper(context, paths, parentMapper);
+                parentMapper = parentMapperTuple.v2();
+                ObjectMapper.Dynamic dynamic = dynamicOrDefault(parentMapper, context);
+                if (dynamic == ObjectMapper.Dynamic.STRICT) {
+                    throw new StrictDynamicMappingException(parentMapper.fullPath(), arrayFieldName);
+                } else if (dynamic == ObjectMapper.Dynamic.TRUE) {
+                    Mapper.Builder builder = context.root().findTemplateBuilder(context, arrayFieldName, XContentFieldType.OBJECT);
+                    if (builder == null) {
                         parseNonDynamicArray(context, parentMapper, lastFieldName, arrayFieldName);
+                    } else {
+                        Mapper.BuilderContext builderContext = new Mapper.BuilderContext(
+                            context.indexSettings().getSettings(),
+                            context.path()
+                        );
+                        mapper = builder.build(builderContext);
+                        assert mapper != null;
+                        if (parsesArrayValue(mapper)) {
+                            context.addDynamicMapper(mapper);
+                            context.path().add(arrayFieldName);
+                            parseObjectOrField(context, mapper);
+                            context.path().remove();
+                        } else {
+                            parseNonDynamicArray(context, parentMapper, lastFieldName, arrayFieldName);
+                        }
                     }
+                } else {
+                    // TODO: shouldn't this skip, not parse?
+                    parseNonDynamicArray(context, parentMapper, lastFieldName, arrayFieldName);
+                }
+                for (int i = 0; i < parentMapperTuple.v1(); i++) {
+                    context.path().remove();
                 }
-            } else {
-                // TODO: shouldn't this skip, not parse?
-                parseNonDynamicArray(context, parentMapper, lastFieldName, arrayFieldName);
-            }
-            for (int i = 0; i < parentMapperTuple.v1(); i++) {
-                context.path().remove();
             }
+        } finally {
+            context.decrementFieldArrayDepth();
         }
     }
 
diff --git a/server/src/main/java/org/opensearch/index/mapper/FieldTypeLookup.java b/server/src/main/java/org/opensearch/index/mapper/FieldTypeLookup.java
index bede143ed5e92..8e1b6f2a3c08b 100644
--- a/server/src/main/java/org/opensearch/index/mapper/FieldTypeLookup.java
+++ b/server/src/main/java/org/opensearch/index/mapper/FieldTypeLookup.java
@@ -153,9 +153,7 @@ public Set<String> sourcePaths(String field) {
             }
         }
 
-        return fieldToCopiedFields.containsKey(resolvedField)
-            ? fieldToCopiedFields.get(resolvedField)
-            : org.opensearch.common.collect.Set.of(resolvedField);
+        return fieldToCopiedFields.containsKey(resolvedField) ? fieldToCopiedFields.get(resolvedField) : Set.of(resolvedField);
     }
 
     @Override
diff --git a/server/src/main/java/org/opensearch/index/mapper/ParseContext.java b/server/src/main/java/org/opensearch/index/mapper/ParseContext.java
index 24f27139f6f4c..12d551edcd3d6 100644
--- a/server/src/main/java/org/opensearch/index/mapper/ParseContext.java
+++ b/server/src/main/java/org/opensearch/index/mapper/ParseContext.java
@@ -38,6 +38,7 @@
 import org.apache.lucene.index.IndexableField;
 import org.apache.lucene.util.BytesRef;
 import org.opensearch.common.xcontent.XContentParser;
+import org.opensearch.OpenSearchParseException;
 import org.opensearch.index.IndexSettings;
 
 import java.util.ArrayList;
@@ -312,6 +313,36 @@ public void addIgnoredField(String field) {
         public Collection<String> getIgnoredFields() {
             return in.getIgnoredFields();
         }
+
+        @Override
+        public void incrementFieldCurrentDepth() {
+            in.incrementFieldCurrentDepth();
+        }
+
+        @Override
+        public void decrementFieldCurrentDepth() {
+            in.decrementFieldCurrentDepth();
+        }
+
+        @Override
+        public void checkFieldDepthLimit() {
+            in.checkFieldDepthLimit();
+        }
+
+        @Override
+        public void incrementFieldArrayDepth() {
+            in.incrementFieldArrayDepth();
+        }
+
+        @Override
+        public void decrementFieldArrayDepth() {
+            in.decrementFieldArrayDepth();
+        }
+
+        @Override
+        public void checkFieldArrayDepthLimit() {
+            in.checkFieldArrayDepthLimit();
+        }
     }
 
     /**
@@ -345,6 +376,14 @@ public static class InternalParseContext extends ParseContext {
 
         private long numNestedDocs;
 
+        private long currentFieldDepth;
+
+        private final long maxAllowedFieldDepth;
+
+        private long currentArrayDepth;
+
+        private final long maxAllowedArrayDepth;
+
         private final List<Mapper> dynamicMappers;
 
         private boolean docsReversed = false;
@@ -371,6 +410,10 @@ public InternalParseContext(
             this.dynamicMappers = new ArrayList<>();
             this.maxAllowedNumNestedDocs = indexSettings.getMappingNestedDocsLimit();
             this.numNestedDocs = 0L;
+            this.currentFieldDepth = 0L;
+            this.currentArrayDepth = 0L;
+            this.maxAllowedFieldDepth = indexSettings.getMappingDepthLimit();
+            this.maxAllowedArrayDepth = indexSettings.getMappingDepthLimit();
         }
 
         @Override
@@ -522,6 +565,60 @@ public void addIgnoredField(String field) {
         public Collection<String> getIgnoredFields() {
             return Collections.unmodifiableCollection(ignoredFields);
         }
+
+        @Override
+        public void incrementFieldCurrentDepth() {
+            this.currentFieldDepth++;
+        }
+
+        @Override
+        public void decrementFieldCurrentDepth() {
+            if (this.currentFieldDepth > 0) {
+                this.currentFieldDepth--;
+            }
+        }
+
+        @Override
+        public void checkFieldDepthLimit() {
+            if (this.currentFieldDepth > maxAllowedFieldDepth) {
+                this.currentFieldDepth = 0;
+                throw new OpenSearchParseException(
+                    "The depth of the field has exceeded the allowed limit of ["
+                        + maxAllowedFieldDepth
+                        + "]."
+                        + " This limit can be set by changing the ["
+                        + MapperService.INDEX_MAPPING_DEPTH_LIMIT_SETTING.getKey()
+                        + "] index level setting."
+                );
+            }
+        }
+
+        @Override
+        public void incrementFieldArrayDepth() {
+            this.currentArrayDepth++;
+        }
+
+        @Override
+        public void decrementFieldArrayDepth() {
+            if (this.currentArrayDepth > 0) {
+                this.currentArrayDepth--;
+            }
+        }
+
+        @Override
+        public void checkFieldArrayDepthLimit() {
+            if (this.currentArrayDepth > maxAllowedArrayDepth) {
+                this.currentArrayDepth = 0;
+                throw new OpenSearchParseException(
+                    "The depth of the nested array field has exceeded the allowed limit of ["
+                        + maxAllowedArrayDepth
+                        + "]."
+                        + " This limit can be set by changing the ["
+                        + MapperService.INDEX_MAPPING_DEPTH_LIMIT_SETTING.getKey()
+                        + "] index level setting."
+                );
+            }
+        }
     }
 
     /**
@@ -687,4 +784,17 @@ public final <T> T parseExternalValue(Class<T> clazz) {
      * Get dynamic mappers created while parsing.
      */
     public abstract List<Mapper> getDynamicMappers();
+
+    public abstract void incrementFieldCurrentDepth();
+
+    public abstract void decrementFieldCurrentDepth();
+
+    public abstract void checkFieldDepthLimit();
+
+    public abstract void incrementFieldArrayDepth();
+
+    public abstract void decrementFieldArrayDepth();
+
+    public abstract void checkFieldArrayDepthLimit();
+
 }
diff --git a/server/src/main/java/org/opensearch/index/mapper/SourceValueFetcher.java b/server/src/main/java/org/opensearch/index/mapper/SourceValueFetcher.java
index d602fceeed041..69f53ba126790 100644
--- a/server/src/main/java/org/opensearch/index/mapper/SourceValueFetcher.java
+++ b/server/src/main/java/org/opensearch/index/mapper/SourceValueFetcher.java
@@ -75,7 +75,7 @@ public List<Object> fetchValues(SourceLookup lookup) {
         for (String path : sourcePaths) {
             Object sourceValue = lookup.extractValue(path, nullValue);
             if (sourceValue == null) {
-                return org.opensearch.common.collect.List.of();
+                return List.of();
             }
 
             // We allow source values to contain multiple levels of arrays, such as `"field": [[1, 2]]`.
diff --git a/server/src/main/java/org/opensearch/index/seqno/ReplicationTracker.java b/server/src/main/java/org/opensearch/index/seqno/ReplicationTracker.java
index 13ff1b91727eb..6edf008fc35b3 100644
--- a/server/src/main/java/org/opensearch/index/seqno/ReplicationTracker.java
+++ b/server/src/main/java/org/opensearch/index/seqno/ReplicationTracker.java
@@ -34,6 +34,7 @@
 
 import com.carrotsearch.hppc.ObjectLongHashMap;
 import com.carrotsearch.hppc.ObjectLongMap;
+import org.apache.logging.log4j.message.ParameterizedMessage;
 import org.opensearch.LegacyESVersion;
 import org.opensearch.Version;
 import org.opensearch.action.ActionListener;
@@ -48,14 +49,18 @@
 import org.opensearch.common.io.stream.StreamInput;
 import org.opensearch.common.io.stream.StreamOutput;
 import org.opensearch.common.io.stream.Writeable;
+import org.opensearch.common.util.concurrent.ConcurrentCollections;
 import org.opensearch.common.xcontent.NamedXContentRegistry;
 import org.opensearch.gateway.WriteStateException;
 import org.opensearch.index.IndexSettings;
+import org.opensearch.index.SegmentReplicationShardStats;
 import org.opensearch.index.engine.SafeCommitInfo;
 import org.opensearch.index.shard.AbstractIndexShardComponent;
 import org.opensearch.index.shard.IndexShard;
 import org.opensearch.index.shard.ReplicationGroup;
 import org.opensearch.index.shard.ShardId;
+import org.opensearch.indices.replication.checkpoint.ReplicationCheckpoint;
+import org.opensearch.indices.replication.common.ReplicationTimer;
 
 import java.io.IOException;
 import java.nio.file.Path;
@@ -68,6 +73,7 @@
 import java.util.Objects;
 import java.util.OptionalLong;
 import java.util.Set;
+import java.util.concurrent.atomic.AtomicLong;
 import java.util.function.BiConsumer;
 import java.util.function.Consumer;
 import java.util.function.Function;
@@ -243,6 +249,8 @@ public class ReplicationTracker extends AbstractIndexShardComponent implements L
 
     private final Consumer<ReplicationGroup> onReplicationGroupUpdated;
 
+    private volatile ReplicationCheckpoint lastPublishedReplicationCheckpoint;
+
     /**
      * Get all retention leases tracked on this shard.
      *
@@ -699,12 +707,29 @@ public static class CheckpointState implements Writeable {
          */
         boolean replicated;
 
+        /**
+         * The currently searchable replication checkpoint.
+         */
+        ReplicationCheckpoint visibleReplicationCheckpoint;
+
+        /**
+         * Map of ReplicationCheckpoints to ReplicationTimers.  Timers are added as new checkpoints are published, and removed when
+         * the replica is caught up.
+         */
+        Map<ReplicationCheckpoint, ReplicationTimer> checkpointTimers;
+
+        /**
+         * The time it took to complete the most recent replication event.
+         */
+        long lastCompletedReplicationLag;
+
         public CheckpointState(long localCheckpoint, long globalCheckpoint, boolean inSync, boolean tracked, boolean replicated) {
             this.localCheckpoint = localCheckpoint;
             this.globalCheckpoint = globalCheckpoint;
             this.inSync = inSync;
             this.tracked = tracked;
             this.replicated = replicated;
+            this.checkpointTimers = ConcurrentCollections.newConcurrentMap();
         }
 
         public CheckpointState(StreamInput in) throws IOException {
@@ -1137,6 +1162,116 @@ public synchronized void updateGlobalCheckpointForShard(final String allocationI
         assert invariant();
     }
 
+    /**
+     * Update the local knowledge of the visible checkpoint for the specified allocation ID.
+     *
+     * This method will also stop timers for each shard and compute replication lag metrics.
+     *
+     * @param allocationId     the allocation ID to update the global checkpoint for
+     * @param visibleCheckpoint the visible checkpoint
+     */
+    public synchronized void updateVisibleCheckpointForShard(final String allocationId, final ReplicationCheckpoint visibleCheckpoint) {
+        assert indexSettings.isSegRepEnabled();
+        assert primaryMode;
+        assert handoffInProgress == false;
+        assert invariant();
+        final CheckpointState cps = checkpoints.get(allocationId);
+        assert !this.shardAllocationId.equals(allocationId) && cps != null;
+        if (cps.checkpointTimers.isEmpty() == false) {
+            // stop any timers for checkpoints up to the received cp and remove from cps.checkpointTimers.
+            // Compute the max lag from the set of completed timers.
+            final AtomicLong lastFinished = new AtomicLong(0L);
+            cps.checkpointTimers.entrySet().removeIf((entry) -> {
+                boolean result = visibleCheckpoint.equals(entry.getKey()) || visibleCheckpoint.isAheadOf(entry.getKey());
+                if (result) {
+                    final ReplicationTimer timer = entry.getValue();
+                    timer.stop();
+                    lastFinished.set(Math.max(lastFinished.get(), timer.time()));
+                }
+                return result;
+            });
+            cps.lastCompletedReplicationLag = lastFinished.get();
+        }
+        logger.trace(
+            () -> new ParameterizedMessage(
+                "updated local knowledge for [{}] on the primary of the visible checkpoint from [{}] to [{}], active timers {}",
+                allocationId,
+                cps.visibleReplicationCheckpoint,
+                visibleCheckpoint,
+                cps.checkpointTimers.keySet()
+            )
+        );
+        cps.visibleReplicationCheckpoint = visibleCheckpoint;
+        assert invariant();
+    }
+
+    /**
+     * After a new checkpoint is published, start a timer for each replica to the checkpoint.
+     * @param checkpoint {@link ReplicationCheckpoint}
+     */
+    public synchronized void setLatestReplicationCheckpoint(ReplicationCheckpoint checkpoint) {
+        assert indexSettings.isSegRepEnabled();
+        assert primaryMode;
+        assert handoffInProgress == false;
+        if (checkpoint.equals(lastPublishedReplicationCheckpoint) == false) {
+            this.lastPublishedReplicationCheckpoint = checkpoint;
+            for (Map.Entry<String, CheckpointState> entry : checkpoints.entrySet()) {
+                if (entry.getKey().equals(this.shardAllocationId) == false) {
+                    final CheckpointState cps = entry.getValue();
+                    if (cps.inSync) {
+                        cps.checkpointTimers.computeIfAbsent(checkpoint, ignored -> {
+                            final ReplicationTimer replicationTimer = new ReplicationTimer();
+                            replicationTimer.start();
+                            return replicationTimer;
+                        });
+                        logger.trace(
+                            () -> new ParameterizedMessage(
+                                "updated last published checkpoint to {} - timers [{}]",
+                                checkpoint,
+                                cps.checkpointTimers.keySet()
+                            )
+                        );
+                    }
+                }
+            }
+        }
+    }
+
+    /**
+     * Fetch stats on segment replication.
+     * @return {@link Tuple} V1 - TimeValue in ms - mean replication lag for this primary to its entire group,
+     * V2 - Set of {@link SegmentReplicationShardStats} per shard in this primary's replication group.
+     */
+    public synchronized Set<SegmentReplicationShardStats> getSegmentReplicationStats() {
+        assert indexSettings.isSegRepEnabled();
+        final ReplicationCheckpoint lastPublishedCheckpoint = this.lastPublishedReplicationCheckpoint;
+        if (primaryMode && lastPublishedCheckpoint != null) {
+            return this.checkpoints.entrySet()
+                .stream()
+                .filter(entry -> entry.getKey().equals(this.shardAllocationId) == false && entry.getValue().inSync)
+                .map(entry -> buildShardStats(lastPublishedCheckpoint.getLength(), entry.getKey(), entry.getValue()))
+                .collect(Collectors.toUnmodifiableSet());
+        }
+        return Collections.emptySet();
+    }
+
+    private SegmentReplicationShardStats buildShardStats(
+        final long latestCheckpointLength,
+        final String allocationId,
+        final CheckpointState checkpointState
+    ) {
+        final Map<ReplicationCheckpoint, ReplicationTimer> checkpointTimers = checkpointState.checkpointTimers;
+        return new SegmentReplicationShardStats(
+            allocationId,
+            checkpointTimers.size(),
+            checkpointState.visibleReplicationCheckpoint == null
+                ? latestCheckpointLength
+                : Math.max(latestCheckpointLength - checkpointState.visibleReplicationCheckpoint.getLength(), 0),
+            checkpointTimers.values().stream().mapToLong(ReplicationTimer::time).max().orElse(0),
+            checkpointState.lastCompletedReplicationLag
+        );
+    }
+
     /**
      * Initializes the global checkpoint tracker in primary mode (see {@link #primaryMode}. Called on primary activation or promotion.
      */
diff --git a/server/src/main/java/org/opensearch/index/shard/CheckpointRefreshListener.java b/server/src/main/java/org/opensearch/index/shard/CheckpointRefreshListener.java
index fb046e2310d93..66d095878d123 100644
--- a/server/src/main/java/org/opensearch/index/shard/CheckpointRefreshListener.java
+++ b/server/src/main/java/org/opensearch/index/shard/CheckpointRefreshListener.java
@@ -40,8 +40,8 @@ public void beforeRefresh() throws IOException {
 
     @Override
     public void afterRefresh(boolean didRefresh) throws IOException {
-        if (didRefresh && shard.state() != IndexShardState.CLOSED && shard.getReplicationTracker().isPrimaryMode()) {
-            publisher.publish(shard);
+        if (didRefresh && shard.state() == IndexShardState.STARTED && shard.getReplicationTracker().isPrimaryMode()) {
+            publisher.publish(shard, shard.getLatestReplicationCheckpoint());
         }
     }
 }
diff --git a/server/src/main/java/org/opensearch/index/shard/IndexShard.java b/server/src/main/java/org/opensearch/index/shard/IndexShard.java
index dd180b95e6b96..b95af8621493b 100644
--- a/server/src/main/java/org/opensearch/index/shard/IndexShard.java
+++ b/server/src/main/java/org/opensearch/index/shard/IndexShard.java
@@ -107,6 +107,7 @@
 import org.opensearch.index.IndexNotFoundException;
 import org.opensearch.index.IndexService;
 import org.opensearch.index.IndexSettings;
+import org.opensearch.index.SegmentReplicationShardStats;
 import org.opensearch.index.VersionType;
 import org.opensearch.index.cache.IndexCache;
 import org.opensearch.index.cache.bitset.ShardBitsetFilterCache;
@@ -568,6 +569,12 @@ public void updateShardState(
                     : "a primary relocation is completed by the cluster-managerr, but primary mode is not active " + currentRouting;
 
                 changeState(IndexShardState.STARTED, "global state is [" + newRouting.state() + "]");
+
+                // Flush here after relocation of primary, so that replica get all changes from new primary rather than waiting for more
+                // docs to get indexed.
+                if (indexSettings.isSegRepEnabled()) {
+                    flush(new FlushRequest().waitIfOngoing(true).force(true));
+                }
             } else if (currentRouting.primary()
                 && currentRouting.relocating()
                 && replicationTracker.isRelocated()
@@ -1423,9 +1430,17 @@ public GatedCloseable<IndexCommit> acquireLastIndexCommit(boolean flushFirst) th
         }
     }
 
-    public void finalizeReplication(SegmentInfos infos, long seqNo) throws IOException {
+    public Optional<NRTReplicationEngine> getReplicationEngine() {
+        if (getEngine() instanceof NRTReplicationEngine) {
+            return Optional.of((NRTReplicationEngine) getEngine());
+        } else {
+            return Optional.empty();
+        }
+    }
+
+    public void finalizeReplication(SegmentInfos infos) throws IOException {
         if (getReplicationEngine().isPresent()) {
-            getReplicationEngine().get().updateSegments(infos, seqNo);
+            getReplicationEngine().get().updateSegments(infos);
         }
     }
 
@@ -1486,8 +1501,12 @@ public Tuple<GatedCloseable<SegmentInfos>, ReplicationCheckpoint> getLatestSegme
                         this.shardId,
                         getOperationPrimaryTerm(),
                         segmentInfos.getGeneration(),
-                        shardRouting.primary() ? getEngine().getMaxSeqNoFromSegmentInfos(segmentInfos) : getProcessedLocalCheckpoint(),
-                        segmentInfos.getVersion()
+                        segmentInfos.getVersion(),
+                        // TODO: Update replicas to compute length from SegmentInfos. Replicas do not yet incref segments with
+                        // getSegmentInfosSnapshot, so computing length from SegmentInfos can cause issues.
+                        shardRouting.primary()
+                            ? store.getSegmentMetadataMap(segmentInfos).values().stream().mapToLong(StoreFileMetadata::length).sum()
+                            : store.stats(StoreStats.UNKNOWN_RESERVED_BYTES).getSizeInBytes()
                     )
                 );
             } catch (IOException e) {
@@ -1510,7 +1529,7 @@ public boolean isSegmentReplicationAllowed() {
             return false;
         }
         if (this.routingEntry().primary()) {
-            logger.warn("Shard is marked as primary and cannot perform segment replication as a replica");
+            logger.warn("Shard routing is marked primary thus cannot perform segment replication as replica");
             return false;
         }
         if (state().equals(IndexShardState.STARTED) == false
@@ -1734,6 +1753,10 @@ public void resetToWriteableEngine() throws IOException, InterruptedException, T
         indexShardOperationPermits.blockOperations(30, TimeUnit.MINUTES, () -> { resetEngineToGlobalCheckpoint(); });
     }
 
+    public void onCheckpointPublished(ReplicationCheckpoint checkpoint) {
+        replicationTracker.setLatestReplicationCheckpoint(checkpoint);
+    }
+
     /**
      * Wrapper for a non-closing reader
      *
@@ -2698,6 +2721,29 @@ public void updateGlobalCheckpointForShard(final String allocationId, final long
         replicationTracker.updateGlobalCheckpointForShard(allocationId, globalCheckpoint);
     }
 
+    /**
+     * Update the local knowledge of the visible global checkpoint for the specified allocation ID.
+     *
+     * @param allocationId     the allocation ID to update the global checkpoint for
+     * @param visibleCheckpoint the visible checkpoint
+     */
+    public void updateVisibleCheckpointForShard(final String allocationId, final ReplicationCheckpoint visibleCheckpoint) {
+        // Update target replication checkpoint only when in active primary mode
+        if (shardRouting.primary() && replicationTracker.isPrimaryMode()) {
+            verifyNotClosed();
+            replicationTracker.updateVisibleCheckpointForShard(allocationId, visibleCheckpoint);
+        }
+    }
+
+    /**
+     * Fetch stats on segment replication.
+     * @return {@link Tuple} V1 - TimeValue in ms - mean replication lag for this primary to its entire group,
+     * V2 - Set of {@link SegmentReplicationShardStats} per shard in this primary's replication group.
+     */
+    public Set<SegmentReplicationShardStats> getReplicationStats() {
+        return replicationTracker.getSegmentReplicationStats();
+    }
+
     /**
      * Add a global checkpoint listener. If the global checkpoint is equal to or above the global checkpoint the listener is waiting for,
      * then the listener will be notified immediately via an executor (so possibly not on the current thread). If the specified timeout
@@ -2935,14 +2981,6 @@ public long getProcessedLocalCheckpoint() {
         });
     }
 
-    private Optional<NRTReplicationEngine> getReplicationEngine() {
-        if (getEngine() instanceof NRTReplicationEngine) {
-            return Optional.of((NRTReplicationEngine) getEngine());
-        } else {
-            return Optional.empty();
-        }
-    }
-
     /**
      * Returns the global checkpoint for the shard.
      *
diff --git a/server/src/main/java/org/opensearch/index/shard/ShardPath.java b/server/src/main/java/org/opensearch/index/shard/ShardPath.java
index e67931844b773..6de0ffc88e0b7 100644
--- a/server/src/main/java/org/opensearch/index/shard/ShardPath.java
+++ b/server/src/main/java/org/opensearch/index/shard/ShardPath.java
@@ -135,7 +135,7 @@ public boolean isCustomDataPath() {
      */
     public static ShardPath loadFileCachePath(NodeEnvironment env, ShardId shardId) {
         NodeEnvironment.NodePath path = env.fileCacheNodePath();
-        final Path dataPath = env.resolveCustomLocation(path.fileCachePath.toString(), shardId);
+        final Path dataPath = env.resolveFileCacheLocation(path.fileCachePath, shardId);
         final Path statePath = path.resolve(shardId);
         return new ShardPath(true, dataPath, statePath, shardId);
     }
diff --git a/server/src/main/java/org/opensearch/index/store/remote/directory/RemoteSnapshotDirectoryFactory.java b/server/src/main/java/org/opensearch/index/store/remote/directory/RemoteSnapshotDirectoryFactory.java
index d39b823df4d3c..2c7e66b9a121d 100644
--- a/server/src/main/java/org/opensearch/index/store/remote/directory/RemoteSnapshotDirectoryFactory.java
+++ b/server/src/main/java/org/opensearch/index/store/remote/directory/RemoteSnapshotDirectoryFactory.java
@@ -73,7 +73,8 @@ private Future<RemoteSnapshotDirectory> createRemoteSnapshotDirectoryFromSnapsho
         ShardPath localShardPath,
         BlobStoreRepository blobStoreRepository
     ) throws IOException {
-        final BlobPath blobPath = new BlobPath().add("indices")
+        final BlobPath blobPath = blobStoreRepository.basePath()
+            .add("indices")
             .add(IndexSettings.SEARCHABLE_SNAPSHOT_INDEX_ID.get(indexSettings.getSettings()))
             .add(Integer.toString(localShardPath.getShardId().getId()));
         final SnapshotId snapshotId = new SnapshotId(
diff --git a/server/src/main/java/org/opensearch/index/store/remote/file/OnDemandBlockIndexInput.java b/server/src/main/java/org/opensearch/index/store/remote/file/OnDemandBlockIndexInput.java
index e97f093bb7703..7319a5324777a 100644
--- a/server/src/main/java/org/opensearch/index/store/remote/file/OnDemandBlockIndexInput.java
+++ b/server/src/main/java/org/opensearch/index/store/remote/file/OnDemandBlockIndexInput.java
@@ -63,20 +63,13 @@ abstract class OnDemandBlockIndexInput extends IndexInput implements RandomAcces
      */
     protected final boolean isClone;
 
-    // Variables needed for block calculation and fetching logic
     /**
-     * Block size shift (default value is 13 = 8KB)
+     * Variables used for block calculation and fetching. blockSize must be a
+     * power of two, and is defined as 2^blockShiftSize. blockMask is defined
+     * as blockSize - 1 and is used to calculate the offset within a block.
      */
     protected final int blockSizeShift;
-
-    /**
-     * Fixed block size
-     */
     protected final int blockSize;
-
-    /**
-     * Block mask
-     */
     protected final int blockMask;
 
     /**
@@ -380,8 +373,8 @@ public static Builder builder() {
     }
 
     public static class Builder {
-        // Block size shift (default value is 13 = 8KB)
-        public static final int DEFAULT_BLOCK_SIZE_SHIFT = 13;
+        // Block size shift (default value is 23 == 2^23 == 8MiB)
+        public static final int DEFAULT_BLOCK_SIZE_SHIFT = 23;
         public static final int DEFAULT_BLOCK_SIZE = 1 << DEFAULT_BLOCK_SIZE_SHIFT;;
 
         private String resourceDescription;
diff --git a/server/src/main/java/org/opensearch/index/store/remote/file/OnDemandBlockSnapshotIndexInput.java b/server/src/main/java/org/opensearch/index/store/remote/file/OnDemandBlockSnapshotIndexInput.java
index 6a873d4531939..b3f8ee9c1817e 100644
--- a/server/src/main/java/org/opensearch/index/store/remote/file/OnDemandBlockSnapshotIndexInput.java
+++ b/server/src/main/java/org/opensearch/index/store/remote/file/OnDemandBlockSnapshotIndexInput.java
@@ -144,13 +144,7 @@ protected IndexInput fetchBlock(int blockId) throws IOException {
             .directory(directory)
             .fileName(blockFileName)
             .build();
-        try {
-            return transferManager.fetchBlob(blobFetchRequest);
-        } catch (InterruptedException e) {
-            logger.error("Interrupted while fetching [{}]", blobFetchRequest);
-            Thread.currentThread().interrupt();
-            throw new IllegalStateException(e);
-        }
+        return transferManager.fetchBlob(blobFetchRequest);
     }
 
     @Override
diff --git a/server/src/main/java/org/opensearch/index/store/remote/filecache/FileCache.java b/server/src/main/java/org/opensearch/index/store/remote/filecache/FileCache.java
index 6b8816f5f3374..2f5693415216b 100644
--- a/server/src/main/java/org/opensearch/index/store/remote/filecache/FileCache.java
+++ b/server/src/main/java/org/opensearch/index/store/remote/filecache/FileCache.java
@@ -12,10 +12,16 @@
 import org.opensearch.index.store.remote.utils.cache.RefCountedCache;
 import org.opensearch.index.store.remote.utils.cache.SegmentedCache;
 import org.opensearch.index.store.remote.utils.cache.stats.CacheStats;
+
+import java.io.IOException;
+import java.io.UncheckedIOException;
+import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.Map;
+import java.util.List;
 import java.util.function.BiFunction;
 
+import static org.opensearch.index.store.remote.directory.RemoteSnapshotDirectoryFactory.LOCAL_STORE_LOCATION;
+
 /**
  * File Cache (FC) is introduced to solve the problem that the local disk cannot hold
  * the entire dataset on remote store. It maintains a node level view of index files with priorities,
@@ -45,21 +51,17 @@ public long capacity() {
         return theCache.capacity();
     }
 
+    @Override
     public CachedIndexInput put(Path filePath, CachedIndexInput indexInput) {
         return theCache.put(filePath, indexInput);
     }
 
     @Override
-    public void putAll(Map<? extends Path, ? extends CachedIndexInput> m) {
-        theCache.putAll(m);
-    }
-
-    @Override
-    public CachedIndexInput computeIfPresent(
+    public CachedIndexInput compute(
         Path key,
         BiFunction<? super Path, ? super CachedIndexInput, ? extends CachedIndexInput> remappingFunction
     ) {
-        return theCache.computeIfPresent(key, remappingFunction);
+        return theCache.compute(key, remappingFunction);
     }
 
     /**
@@ -84,11 +86,6 @@ public void remove(final Path filePath) {
         theCache.remove(filePath);
     }
 
-    @Override
-    public void removeAll(Iterable<? extends Path> keys) {
-        theCache.removeAll(keys);
-    }
-
     @Override
     public void clear() {
         theCache.clear();
@@ -123,4 +120,37 @@ public CacheUsage usage() {
     public CacheStats stats() {
         return theCache.stats();
     }
+
+    /**
+     * Restores the file cache instance performing a folder scan of the
+     * {@link org.opensearch.index.store.remote.directory.RemoteSnapshotDirectoryFactory#LOCAL_STORE_LOCATION}
+     * directory within the provided file cache path.
+     */
+    public void restoreFromDirectory(List<Path> fileCacheDataPaths) {
+        fileCacheDataPaths.stream()
+            .filter(Files::isDirectory)
+            .map(path -> path.resolve(LOCAL_STORE_LOCATION))
+            .filter(Files::isDirectory)
+            .flatMap(dir -> {
+                try {
+                    return Files.list(dir);
+                } catch (IOException e) {
+                    throw new UncheckedIOException(
+                        "Unable to process file cache directory. Please clear the file cache for node startup.",
+                        e
+                    );
+                }
+            })
+            .filter(Files::isRegularFile)
+            .forEach(path -> {
+                try {
+                    put(path.toAbsolutePath(), new FileCachedIndexInput.ClosedIndexInput(Files.size(path)));
+                } catch (IOException e) {
+                    throw new UncheckedIOException(
+                        "Unable to retrieve cache file details. Please clear the file cache for node startup.",
+                        e
+                    );
+                }
+            });
+    }
 }
diff --git a/server/src/main/java/org/opensearch/index/store/remote/filecache/FileCachedIndexInput.java b/server/src/main/java/org/opensearch/index/store/remote/filecache/FileCachedIndexInput.java
index a062254736878..a75ed001f0db3 100644
--- a/server/src/main/java/org/opensearch/index/store/remote/filecache/FileCachedIndexInput.java
+++ b/server/src/main/java/org/opensearch/index/store/remote/filecache/FileCachedIndexInput.java
@@ -161,4 +161,61 @@ public void close() throws IOException {
     public boolean isClosed() {
         return closed;
     }
+
+    /**
+     * IndexInput instance which is utilized to fetch length for the input without opening the IndexInput.
+     */
+    public static class ClosedIndexInput extends CachedIndexInput {
+        private final long length;
+
+        public ClosedIndexInput(long length) {
+            super("ClosedIndexInput");
+            this.length = length;
+        }
+
+        @Override
+        public void close() throws IOException {
+            // No-Op
+        }
+
+        @Override
+        public long getFilePointer() {
+            throw new UnsupportedOperationException("ClosedIndexInput doesn't support getFilePointer().");
+        }
+
+        @Override
+        public void seek(long pos) throws IOException {
+            throw new UnsupportedOperationException("ClosedIndexInput doesn't support seek().");
+        }
+
+        @Override
+        public long length() {
+            return length;
+        }
+
+        @Override
+        public IndexInput slice(String sliceDescription, long offset, long length) throws IOException {
+            throw new UnsupportedOperationException("ClosedIndexInput couldn't be sliced.");
+        }
+
+        @Override
+        public byte readByte() throws IOException {
+            throw new UnsupportedOperationException("ClosedIndexInput doesn't support read.");
+        }
+
+        @Override
+        public void readBytes(byte[] b, int offset, int len) throws IOException {
+            throw new UnsupportedOperationException("ClosedIndexInput doesn't support read.");
+        }
+
+        @Override
+        public IndexInput clone() {
+            throw new UnsupportedOperationException("ClosedIndexInput cannot be cloned.");
+        }
+
+        @Override
+        public boolean isClosed() {
+            return true;
+        }
+    }
 }
diff --git a/server/src/main/java/org/opensearch/index/store/remote/utils/ConcurrentInvocationLinearizer.java b/server/src/main/java/org/opensearch/index/store/remote/utils/ConcurrentInvocationLinearizer.java
deleted file mode 100644
index 2b55377bc17b9..0000000000000
--- a/server/src/main/java/org/opensearch/index/store/remote/utils/ConcurrentInvocationLinearizer.java
+++ /dev/null
@@ -1,87 +0,0 @@
-/*
- * SPDX-License-Identifier: Apache-2.0
- *
- * The OpenSearch Contributors require contributions made to
- * this file be licensed under the Apache-2.0 license or a
- * compatible open source license.
- */
-
-package org.opensearch.index.store.remote.utils;
-
-import java.io.IOException;
-import java.util.Collections;
-import java.util.Map;
-import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.ConcurrentHashMap;
-import java.util.concurrent.ConcurrentMap;
-import java.util.concurrent.ExecutionException;
-
-import org.opensearch.common.CheckedFunction;
-
-/**
- * A utility class which can be used to serialize concurrent invocations and to achieve "invoke simultaneously once at any time"
- * semantic. This class does not implement any concurrency itself. When there is no concurrent access the work will be performed
- * on the calling thread, though the result of that work will be shared with any concurrent requests for the same key.
- *
- * @param <METHOD_PARAM_TYPE> the method parameter type where this method invocation will be linearized
- * @param <RET_TYPE>          return type of the method
- * @opensearch.internal
- */
-class ConcurrentInvocationLinearizer<METHOD_PARAM_TYPE, RET_TYPE> {
-    private final ConcurrentMap<METHOD_PARAM_TYPE, CompletableFuture<RET_TYPE>> invokeOnceCache = new ConcurrentHashMap<>();
-
-    /**
-     * Invokes the given function. If another thread is concurrently invoking the same function, as
-     * identified by the given input, then this call will block and return the result of that
-     * computation. Otherwise it will synchronously invoke the given function and return the result.
-     * @param input The input to uniquely identify this function
-     * @param function The function to invoke
-     * @return The result of the function
-     * @throws InterruptedException thrown if interrupted while blocking
-     * @throws IOException thrown from given function
-     */
-    RET_TYPE linearize(METHOD_PARAM_TYPE input, CheckedFunction<METHOD_PARAM_TYPE, RET_TYPE, IOException> function)
-        throws InterruptedException, IOException {
-        try {
-            return linearizeInternal(input, function).get();
-        } catch (ExecutionException e) {
-            if (e.getCause() instanceof IOException) {
-                throw (IOException) e.getCause();
-            } else if (e.getCause() instanceof RuntimeException) {
-                throw (RuntimeException) e.getCause();
-            } else if (e.getCause() instanceof Error) {
-                throw (Error) e.getCause();
-            }
-            throw new RuntimeException("Unknown exception cause", e.getCause());
-        }
-    }
-
-    // Visible for testing
-    CompletableFuture<RET_TYPE> linearizeInternal(
-        METHOD_PARAM_TYPE input,
-        CheckedFunction<METHOD_PARAM_TYPE, RET_TYPE, IOException> function
-    ) {
-        final CompletableFuture<RET_TYPE> newFuture = new CompletableFuture<>();
-        final CompletableFuture<RET_TYPE> existing = invokeOnceCache.putIfAbsent(input, newFuture);
-        if (existing == null) {
-            // No concurrent work is happening for this key, so need to do the
-            // work and complete the future with the result.
-            try {
-                newFuture.complete(function.apply(input));
-            } catch (Throwable e) {
-                newFuture.completeExceptionally(e);
-            } finally {
-                invokeOnceCache.remove(input);
-            }
-            return newFuture;
-        } else {
-            // Another thread is doing the work, so return the future to its result
-            return existing;
-        }
-    }
-
-    // Visible for testing
-    Map<METHOD_PARAM_TYPE, CompletableFuture<RET_TYPE>> getInvokeOnceCache() {
-        return Collections.unmodifiableMap(invokeOnceCache);
-    }
-}
diff --git a/server/src/main/java/org/opensearch/index/store/remote/utils/TransferManager.java b/server/src/main/java/org/opensearch/index/store/remote/utils/TransferManager.java
index 6f015fe810daf..976827d582745 100644
--- a/server/src/main/java/org/opensearch/index/store/remote/utils/TransferManager.java
+++ b/server/src/main/java/org/opensearch/index/store/remote/utils/TransferManager.java
@@ -22,7 +22,6 @@
 import java.io.OutputStream;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.Objects;
 
 /**
  * This acts as entry point to fetch {@link BlobFetchRequest} and return actual {@link IndexInput}. Utilizes the BlobContainer interface to
@@ -34,12 +33,10 @@ public class TransferManager {
     private static final Logger logger = LogManager.getLogger(TransferManager.class);
 
     private final BlobContainer blobContainer;
-    private final ConcurrentInvocationLinearizer<Path, IndexInput> invocationLinearizer;
     private final FileCache fileCache;
 
     public TransferManager(final BlobContainer blobContainer, final FileCache fileCache) {
         this.blobContainer = blobContainer;
-        this.invocationLinearizer = new ConcurrentInvocationLinearizer<>();
         this.fileCache = fileCache;
     }
 
@@ -48,53 +45,46 @@ public TransferManager(final BlobContainer blobContainer, final FileCache fileCa
      * @param blobFetchRequest to fetch
      * @return future of IndexInput augmented with internal caching maintenance tasks
      */
-    public IndexInput fetchBlob(BlobFetchRequest blobFetchRequest) throws InterruptedException, IOException {
-        final IndexInput indexInput = invocationLinearizer.linearize(
-            blobFetchRequest.getFilePath(),
-            p -> fetchOriginBlob(blobFetchRequest)
-        );
-        return indexInput.clone();
-    }
+    public IndexInput fetchBlob(BlobFetchRequest blobFetchRequest) throws IOException {
+        final Path key = blobFetchRequest.getFilePath();
 
-    /**
-     * Fetches the "origin" IndexInput from the cache, downloading it first if it is
-     * not already cached. This instance must be cloned before using. This method is
-     * accessed through the ConcurrentInvocationLinearizer so read-check-write is
-     * acceptable here
-     */
-    private IndexInput fetchOriginBlob(BlobFetchRequest blobFetchRequest) throws IOException {
-        // check if the origin is already in block cache
-        IndexInput origin = fileCache.computeIfPresent(blobFetchRequest.getFilePath(), (path, cachedIndexInput) -> {
-            if (cachedIndexInput.isClosed()) {
-                // if it's already in the file cache, but closed, open it and replace the original one
+        final IndexInput origin = fileCache.compute(key, (path, cachedIndexInput) -> {
+            if (cachedIndexInput == null) {
                 try {
-                    IndexInput luceneIndexInput = blobFetchRequest.getDirectory().openInput(blobFetchRequest.getFileName(), IOContext.READ);
-                    return new FileCachedIndexInput(fileCache, blobFetchRequest.getFilePath(), luceneIndexInput);
-                } catch (IOException ioe) {
-                    logger.warn("Open index input " + blobFetchRequest.getFilePath() + " got error ", ioe);
-                    // open failed so return null to download the file again
+                    return new FileCachedIndexInput(fileCache, blobFetchRequest.getFilePath(), downloadBlockLocally(blobFetchRequest));
+                } catch (IOException e) {
+                    logger.warn("Failed to download " + blobFetchRequest.getFilePath(), e);
                     return null;
                 }
-
+            } else {
+                if (cachedIndexInput.isClosed()) {
+                    // if it's already in the file cache, but closed, open it and replace the original one
+                    try {
+                        final IndexInput luceneIndexInput = blobFetchRequest.getDirectory()
+                            .openInput(blobFetchRequest.getFileName(), IOContext.READ);
+                        return new FileCachedIndexInput(fileCache, blobFetchRequest.getFilePath(), luceneIndexInput);
+                    } catch (IOException e) {
+                        logger.warn("Failed to open existing file for " + blobFetchRequest.getFilePath(), e);
+                        return null;
+                    }
+                }
+                // already in the cache and ready to be used (open)
+                return cachedIndexInput;
             }
-            // already in the cache and ready to be used (open)
-            return cachedIndexInput;
         });
 
-        if (Objects.isNull(origin)) {
-            // origin is not in file cache, download origin
-
-            // open new origin
-            IndexInput downloaded = downloadBlockLocally(blobFetchRequest);
-
-            // refcount = 0 at the beginning
-            FileCachedIndexInput newOrigin = new FileCachedIndexInput(fileCache, blobFetchRequest.getFilePath(), downloaded);
+        if (origin == null) {
+            throw new IOException("Failed to create IndexInput for " + blobFetchRequest.getFileName());
+        }
 
-            // put origin into file cache
-            fileCache.put(blobFetchRequest.getFilePath(), newOrigin);
-            origin = newOrigin;
+        // Origin was either retrieved from the cache or newly added, either
+        // way the reference count has been incremented by one. We can only
+        // decrement this reference _after_ creating the clone to be returned.
+        try {
+            return origin.clone();
+        } finally {
+            fileCache.decRef(key);
         }
-        return origin;
     }
 
     private IndexInput downloadBlockLocally(BlobFetchRequest blobFetchRequest) throws IOException {
diff --git a/server/src/main/java/org/opensearch/index/store/remote/utils/cache/LRUCache.java b/server/src/main/java/org/opensearch/index/store/remote/utils/cache/LRUCache.java
index b9a9c063fde22..75b28baafe57f 100644
--- a/server/src/main/java/org/opensearch/index/store/remote/utils/cache/LRUCache.java
+++ b/server/src/main/java/org/opensearch/index/store/remote/utils/cache/LRUCache.java
@@ -17,7 +17,6 @@
 import org.opensearch.index.store.remote.utils.cache.stats.StatsCounter;
 
 import java.util.HashMap;
-import java.util.Map;
 import java.util.Objects;
 import java.util.concurrent.locks.ReentrantLock;
 import java.util.function.BiFunction;
@@ -137,9 +136,7 @@ public V get(K key) {
                 return null;
             }
             // hit
-            if (node.evictable()) {
-                lru.moveToBack(node);
-            }
+            incRef(key);
             statsCounter.recordHits(key, 1);
             return node.value;
         } finally {
@@ -147,46 +144,21 @@ public V get(K key) {
         }
     }
 
-    /**
-     * If put a new item to the cache, it's zero referenced.
-     * Otherwise, just replace the node with new value and new weight.
-     */
     @Override
     public V put(K key, V value) {
         Objects.requireNonNull(key);
         Objects.requireNonNull(value);
 
-        final long weight = weigher.weightOf(value);
         final ReentrantLock lock = this.lock;
         lock.lock();
         try {
             Node<K, V> node = data.get(key);
             if (node != null) {
                 final V oldValue = node.value;
-                final long oldWeight = node.weight;
-                // update the value and weight
-                node.value = value;
-                node.weight = weight;
-                // update usage
-                final long weightDiff = weight - oldWeight;
-                if (node.refCount > 0) {
-                    activeUsage += weightDiff;
-                }
-                if (node.evictable()) {
-                    lru.moveToBack(node);
-                }
-                usage += weightDiff;
-                // call listeners
-                statsCounter.recordReplacement();
-                listener.onRemoval(new RemovalNotification<>(key, oldValue, RemovalReason.REPLACED));
-                evict();
+                replaceNode(node, value);
                 return oldValue;
             } else {
-                Node<K, V> newNode = new Node<>(key, value, weight);
-                data.put(key, newNode);
-                lru.add(newNode);
-                usage += weight;
-                evict();
+                addNode(key, value);
                 return null;
             }
         } finally {
@@ -195,63 +167,34 @@ public V put(K key, V value) {
     }
 
     @Override
-    public void putAll(Map<? extends K, ? extends V> m) {
-        for (Map.Entry<? extends K, ? extends V> e : m.entrySet())
-            put(e.getKey(), e.getValue());
-    }
-
-    @Override
-    public V computeIfPresent(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
+    public V compute(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
         Objects.requireNonNull(key);
+        Objects.requireNonNull(remappingFunction);
         final ReentrantLock lock = this.lock;
         lock.lock();
         try {
-            Node<K, V> node = data.get(key);
-            if (node != null && node.value != null) {
-                V v = remappingFunction.apply(key, node.value);
-                if (v != null) {
-                    final V oldValue = node.value;
-                    final long oldWeight = node.weight;
-                    final long weight = weigher.weightOf(v);
-                    // update the value and weight
-                    node.value = v;
-                    node.weight = weight;
-
-                    // update usage
-                    final long weightDiff = weight - oldWeight;
-                    if (node.evictable()) {
-                        lru.moveToBack(node);
-                    }
-
-                    if (node.refCount > 0) {
-                        activeUsage += weightDiff;
-                    }
-
-                    usage += weightDiff;
-                    statsCounter.recordHits(key, 1);
-                    if (oldValue != node.value) {
-                        statsCounter.recordReplacement();
-                        listener.onRemoval(new RemovalNotification<>(node.key, oldValue, RemovalReason.REPLACED));
-                    }
-                    evict();
-                    return v;
+            final Node<K, V> node = data.get(key);
+            if (node == null) {
+                final V newValue = remappingFunction.apply(key, null);
+                if (newValue == null) {
+                    // Remapping function asked for removal, but nothing to remove
+                    return null;
+                } else {
+                    addNode(key, newValue);
+                    statsCounter.recordMisses(key, 1);
+                    return newValue;
+                }
+            } else {
+                final V newValue = remappingFunction.apply(key, node.value);
+                if (newValue == null) {
+                    removeNode(key);
+                    return null;
                 } else {
-                    // is v is null, remove the item
-                    data.remove(key);
-                    if (node.refCount > 0) {
-                        activeUsage -= node.weight;
-                    }
-                    usage -= node.weight;
-                    if (node.evictable()) {
-                        lru.remove(node);
-                    }
-                    statsCounter.recordRemoval(node.weight);
-                    listener.onRemoval(new RemovalNotification<>(node.key, node.value, RemovalReason.EXPLICIT));
+                    statsCounter.recordHits(key, 1);
+                    replaceNode(node, newValue);
+                    return newValue;
                 }
             }
-
-            statsCounter.recordMisses(key, 1);
-            return null;
         } finally {
             lock.unlock();
         }
@@ -263,30 +206,12 @@ public void remove(K key) {
         final ReentrantLock lock = this.lock;
         lock.lock();
         try {
-            Node<K, V> node = data.remove(key);
-            if (node != null) {
-                if (node.refCount > 0) {
-                    activeUsage -= node.weight;
-                }
-                usage -= node.weight;
-                if (node.evictable()) {
-                    lru.remove(node);
-                }
-                statsCounter.recordRemoval(node.weight);
-                listener.onRemoval(new RemovalNotification<>(node.key, node.value, RemovalReason.EXPLICIT));
-            }
+            removeNode(key);
         } finally {
             lock.unlock();
         }
     }
 
-    @Override
-    public void removeAll(Iterable<? extends K> keys) {
-        for (K key : keys) {
-            remove(key);
-        }
-    }
-
     @Override
     public void clear() {
         final ReentrantLock lock = this.lock;
@@ -409,11 +334,56 @@ public CacheStats stats() {
         }
     }
 
-    boolean hasOverflowed() {
+    private void addNode(K key, V value) {
+        final long weight = weigher.weightOf(value);
+        Node<K, V> newNode = new Node<>(key, value, weight);
+        data.put(key, newNode);
+        usage += weight;
+        incRef(key);
+        evict();
+    }
+
+    private void replaceNode(Node<K, V> node, V newValue) {
+        if (node.value != newValue) { // replace if new value is not the same instance as existing value
+            final V oldValue = node.value;
+            final long oldWeight = node.weight;
+            final long newWeight = weigher.weightOf(newValue);
+            // update the value and weight
+            node.value = newValue;
+            node.weight = newWeight;
+            // update usage
+            final long weightDiff = newWeight - oldWeight;
+            if (node.refCount > 0) {
+                activeUsage += weightDiff;
+            }
+            usage += weightDiff;
+            statsCounter.recordReplacement();
+            listener.onRemoval(new RemovalNotification<>(node.key, oldValue, RemovalReason.REPLACED));
+        }
+        incRef(node.key);
+        evict();
+    }
+
+    private void removeNode(K key) {
+        Node<K, V> node = data.remove(key);
+        if (node != null) {
+            if (node.refCount > 0) {
+                activeUsage -= node.weight;
+            }
+            usage -= node.weight;
+            if (node.evictable()) {
+                lru.remove(node);
+            }
+            statsCounter.recordRemoval(node.weight);
+            listener.onRemoval(new RemovalNotification<>(node.key, node.value, RemovalReason.EXPLICIT));
+        }
+    }
+
+    private boolean hasOverflowed() {
         return usage >= capacity;
     }
 
-    void evict() {
+    private void evict() {
         // Attempts to evict entries from the cache if it exceeds the maximum
         // capacity.
         while (hasOverflowed()) {
diff --git a/server/src/main/java/org/opensearch/index/store/remote/utils/cache/RefCountedCache.java b/server/src/main/java/org/opensearch/index/store/remote/utils/cache/RefCountedCache.java
index 7964e41b4f48a..bbb37dc57ae7e 100644
--- a/server/src/main/java/org/opensearch/index/store/remote/utils/cache/RefCountedCache.java
+++ b/server/src/main/java/org/opensearch/index/store/remote/utils/cache/RefCountedCache.java
@@ -10,14 +10,13 @@
 
 import org.opensearch.index.store.remote.utils.cache.stats.CacheStats;
 
-import java.util.Map;
 import java.util.function.BiFunction;
 
 /**
  * Custom Cache which support typical cache operations (put, get, ...) and it support reference counting per individual key which might
  * change eviction behavior
  * @param <K> type of the key
- * @param <V> type of th value
+ * @param <V> type of the value
  *
  * @opensearch.internal
  */
@@ -25,7 +24,8 @@ public interface RefCountedCache<K, V> {
 
     /**
      * Returns the value associated with {@code key} in this cache, or {@code null} if there is no
-     * cached value for {@code key}.
+     * cached value for {@code key}. Retrieving an item automatically increases its reference
+     * count.
      */
     V get(K key);
 
@@ -35,36 +35,28 @@ public interface RefCountedCache<K, V> {
      */
     V put(K key, V value);
 
-    /**
-     * Copies all the mappings from the specified map to the cache. The effect of this call is
-     * equivalent to that of calling {@code put(k, v)} on this map once for each mapping from key
-     * {@code k} to value {@code v} in the specified map. The behavior of this operation is undefined
-     * if the specified map is modified while the operation is in progress.
-     */
-    void putAll(Map<? extends K, ? extends V> m);
-
     /**
      * If the specified key is already associated with a value, attempts to update its value using the given mapping
-     * function and enters the new value into this map unless null.
-     *
-     * If the specified key is NOT already associated with a value, return null without applying the mapping function.
-     *
+     * function and enters the new value. If the mapping function returns null the item is removed from the
+     * cache, regardless of its reference count. If the mapping function returns non-null the value is updated.
+     * The new entry will have the reference count of the previous entry plus one, as this method automatically
+     * increases the reference count by one when it returns the newly mapped value.
+     * <p>
+     * If the specified key is NOT already associated with a value, then the value of the remapping function
+     * will be associated with the given key, and its reference count will be set to one. If the remapping function
+     * returns null then nothing is done.
+     * <p>
      * The remappingFunction method for a given key will be invoked at most once.
      */
-    V computeIfPresent(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction);
+    V compute(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction);
 
     /**
-     * Discards any cached value for key {@code key}.
+     * Discards any cached value for key {@code key}, regardless of reference count.
      */
     void remove(K key);
 
     /**
-     * Discards any cached values for keys {@code keys}.
-     */
-    void removeAll(Iterable<? extends K> keys);
-
-    /**
-     * Discards all entries in the cache.
+     * Discards all entries in the cache, regardless of reference count.
      */
     void clear();
 
@@ -83,6 +75,11 @@ public interface RefCountedCache<K, V> {
      */
     void decRef(K key);
 
+    /**
+     * Removes all cache entries with a reference count of zero, regardless of current capacity.
+     *
+     * @return The total weight of all removed entries.
+     */
     long prune();
 
     /**
diff --git a/server/src/main/java/org/opensearch/index/store/remote/utils/cache/SegmentedCache.java b/server/src/main/java/org/opensearch/index/store/remote/utils/cache/SegmentedCache.java
index 04b0581b41ff5..42e44aa5f6a15 100644
--- a/server/src/main/java/org/opensearch/index/store/remote/utils/cache/SegmentedCache.java
+++ b/server/src/main/java/org/opensearch/index/store/remote/utils/cache/SegmentedCache.java
@@ -13,7 +13,6 @@
 import org.opensearch.common.cache.Weigher;
 import org.opensearch.index.store.remote.utils.cache.stats.CacheStats;
 
-import java.util.Map;
 import java.util.Objects;
 import java.util.function.BiFunction;
 
@@ -91,15 +90,9 @@ public V put(K key, V value) {
     }
 
     @Override
-    public void putAll(Map<? extends K, ? extends V> m) {
-        for (Map.Entry<? extends K, ? extends V> e : m.entrySet())
-            put(e.getKey(), e.getValue());
-    }
-
-    @Override
-    public V computeIfPresent(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
+    public V compute(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
         if (key == null || remappingFunction == null) throw new NullPointerException();
-        return segmentFor(key).computeIfPresent(key, remappingFunction);
+        return segmentFor(key).compute(key, remappingFunction);
     }
 
     @Override
@@ -108,12 +101,6 @@ public void remove(K key) {
         segmentFor(key).remove(key);
     }
 
-    @Override
-    public void removeAll(Iterable<? extends K> keys) {
-        for (K k : keys)
-            remove(k);
-    }
-
     @Override
     public void clear() {
         for (RefCountedCache<K, V> cache : table) {
diff --git a/server/src/main/java/org/opensearch/index/store/remote/utils/cache/stats/StatsCounter.java b/server/src/main/java/org/opensearch/index/store/remote/utils/cache/stats/StatsCounter.java
index 680dc441252dc..b096bb8d652ae 100644
--- a/server/src/main/java/org/opensearch/index/store/remote/utils/cache/stats/StatsCounter.java
+++ b/server/src/main/java/org/opensearch/index/store/remote/utils/cache/stats/StatsCounter.java
@@ -43,7 +43,7 @@ public interface StatsCounter<K> {
      * Records the explicit removal of an entry from the cache. This should only been called when an entry is
      * removed as a result of manual
      * {@link RefCountedCache#remove(Object)}
-     * {@link RefCountedCache#computeIfPresent(Object, BiFunction)}
+     * {@link RefCountedCache#compute(Object, BiFunction)}
      *
      * @param weight the weight of the removed entry
      */
@@ -53,7 +53,7 @@ public interface StatsCounter<K> {
      * Records the replacement of an entry from the cache. This should only been called when an entry is
      * replaced as a result of manual
      * {@link RefCountedCache#put(Object, Object)}
-     * {@link RefCountedCache#computeIfPresent(Object, BiFunction)}
+     * {@link RefCountedCache#compute(Object, BiFunction)}
      */
     void recordReplacement();
 
diff --git a/server/src/main/java/org/opensearch/index/translog/Translog.java b/server/src/main/java/org/opensearch/index/translog/Translog.java
index 3318f6858dc82..f9ddb946b7e59 100644
--- a/server/src/main/java/org/opensearch/index/translog/Translog.java
+++ b/server/src/main/java/org/opensearch/index/translog/Translog.java
@@ -2016,11 +2016,15 @@ public static String createEmptyTranslog(
             EMPTY_TRANSLOG_BUFFER_SIZE,
             minTranslogGeneration,
             initialGlobalCheckpoint,
-            () -> { throw new UnsupportedOperationException(); },
+            () -> {
+                throw new UnsupportedOperationException();
+            },
             () -> { throw new UnsupportedOperationException(); },
             primaryTerm,
             new TragicExceptionHolder(),
-            seqNo -> { throw new UnsupportedOperationException(); },
+            seqNo -> {
+                throw new UnsupportedOperationException();
+            },
             BigArrays.NON_RECYCLING_INSTANCE
         );
         writer.close();
diff --git a/server/src/main/java/org/opensearch/indices/replication/OngoingSegmentReplications.java b/server/src/main/java/org/opensearch/indices/replication/OngoingSegmentReplications.java
index 1a97d334df58f..bf9e4607b695a 100644
--- a/server/src/main/java/org/opensearch/indices/replication/OngoingSegmentReplications.java
+++ b/server/src/main/java/org/opensearch/indices/replication/OngoingSegmentReplications.java
@@ -8,6 +8,9 @@
 
 package org.opensearch.indices.replication;
 
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.message.ParameterizedMessage;
 import org.opensearch.OpenSearchException;
 import org.opensearch.action.ActionListener;
 import org.opensearch.cluster.node.DiscoveryNode;
@@ -26,6 +29,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
@@ -37,6 +41,8 @@
  * @opensearch.internal
  */
 class OngoingSegmentReplications {
+
+    private static final Logger logger = LogManager.getLogger(OngoingSegmentReplications.class);
     private final RecoverySettings recoverySettings;
     private final IndicesService indicesService;
     private final Map<ReplicationCheckpoint, CopyState> copyStateMap;
@@ -115,6 +121,10 @@ void startSegmentCopy(GetSegmentFilesRequest request, ActionListener<GetSegmentF
                 }
             });
             if (request.getFilesToFetch().isEmpty()) {
+                // before completion, alert the primary of the replica's state.
+                handler.getCopyState()
+                    .getShard()
+                    .updateVisibleCheckpointForShard(request.getTargetAllocationId(), handler.getCopyState().getCheckpoint());
                 wrappedListener.onResponse(new GetSegmentFilesResponse(Collections.emptyList()));
             } else {
                 handler.sendFiles(request, wrappedListener);
@@ -137,16 +147,13 @@ void startSegmentCopy(GetSegmentFilesRequest request, ActionListener<GetSegmentF
      */
     CopyState prepareForReplication(CheckpointInfoRequest request, FileChunkWriter fileChunkWriter) throws IOException {
         final CopyState copyState = getCachedCopyState(request.getCheckpoint());
-        if (allocationIdToHandlers.putIfAbsent(
-            request.getTargetAllocationId(),
-            createTargetHandler(request.getTargetNode(), copyState, request.getTargetAllocationId(), fileChunkWriter)
-        ) != null) {
-            throw new OpenSearchException(
-                "Shard copy {} on node {} already replicating",
-                request.getCheckpoint().getShardId(),
-                request.getTargetNode()
-            );
-        }
+        allocationIdToHandlers.compute(request.getTargetAllocationId(), (allocationId, segrepHandler) -> {
+            if (segrepHandler != null) {
+                logger.warn("Override handler for allocation id {}", request.getTargetAllocationId());
+                cancelHandlers(handler -> handler.getAllocationId().equals(request.getTargetAllocationId()), "cancel due to retry");
+            }
+            return createTargetHandler(request.getTargetNode(), copyState, request.getTargetAllocationId(), fileChunkWriter);
+        });
         return copyState;
     }
 
@@ -163,8 +170,8 @@ synchronized void cancel(IndexShard shard, String reason) {
     /**
      * Cancel all Replication events for the given allocation ID, intended to be called when a primary is shutting down.
      *
-     * @param allocationId  {@link String} - Allocation ID.
-     * @param reason {@link String} - Reason for the cancel
+     * @param allocationId {@link String} - Allocation ID.
+     * @param reason       {@link String} - Reason for the cancel
      */
     synchronized void cancel(String allocationId, String reason) {
         final SegmentReplicationSourceHandler handler = allocationIdToHandlers.remove(allocationId);
@@ -195,6 +202,11 @@ int size() {
         return allocationIdToHandlers.size();
     }
 
+    // Visible for tests.
+    Map<String, SegmentReplicationSourceHandler> getHandlers() {
+        return allocationIdToHandlers;
+    }
+
     int cachedCopyStateSize() {
         return copyStateMap.size();
     }
@@ -254,8 +266,25 @@ private void cancelHandlers(Predicate<? super SegmentReplicationSourceHandler> p
             .filter(predicate)
             .map(SegmentReplicationSourceHandler::getAllocationId)
             .collect(Collectors.toList());
+        if (allocationIds.size() == 0) {
+            return;
+        }
+        logger.warn(() -> new ParameterizedMessage("Cancelling replications for allocationIds {}", allocationIds));
         for (String allocationId : allocationIds) {
             cancel(allocationId, reason);
         }
     }
+
+    /**
+     * Clear copystate and target handlers for any non insync allocationIds.
+     * @param shardId {@link ShardId}
+     * @param inSyncAllocationIds {@link List} of in-sync allocation Ids.
+     */
+    public void clearOutOfSyncIds(ShardId shardId, Set<String> inSyncAllocationIds) {
+        cancelHandlers(
+            (handler) -> handler.getCopyState().getShard().shardId().equals(shardId)
+                && inSyncAllocationIds.contains(handler.getAllocationId()) == false,
+            "Shard is no longer in-sync with the primary"
+        );
+    }
 }
diff --git a/server/src/main/java/org/opensearch/indices/replication/PrimaryShardReplicationSource.java b/server/src/main/java/org/opensearch/indices/replication/PrimaryShardReplicationSource.java
index f73028bee42f9..b211d81c1c76a 100644
--- a/server/src/main/java/org/opensearch/indices/replication/PrimaryShardReplicationSource.java
+++ b/server/src/main/java/org/opensearch/indices/replication/PrimaryShardReplicationSource.java
@@ -13,7 +13,6 @@
 import org.opensearch.action.ActionListener;
 import org.opensearch.cluster.node.DiscoveryNode;
 import org.opensearch.common.io.stream.Writeable;
-import org.opensearch.common.unit.TimeValue;
 import org.opensearch.index.store.Store;
 import org.opensearch.index.store.StoreFileMetadata;
 import org.opensearch.indices.recovery.RecoverySettings;
@@ -42,6 +41,7 @@ public class PrimaryShardReplicationSource implements SegmentReplicationSource {
     private final DiscoveryNode sourceNode;
     private final DiscoveryNode targetNode;
     private final String targetAllocationId;
+    private final RecoverySettings recoverySettings;
 
     public PrimaryShardReplicationSource(
         DiscoveryNode targetNode,
@@ -59,6 +59,7 @@ public PrimaryShardReplicationSource(
         );
         this.sourceNode = sourceNode;
         this.targetNode = targetNode;
+        this.recoverySettings = recoverySettings;
     }
 
     @Override
@@ -83,17 +84,6 @@ public void getSegmentFiles(
     ) {
         final Writeable.Reader<GetSegmentFilesResponse> reader = GetSegmentFilesResponse::new;
         final ActionListener<GetSegmentFilesResponse> responseListener = ActionListener.map(listener, r -> r);
-        // Few of the below assumptions and calculations are added for experimental release of segment replication feature in 2.3
-        // version. These can change in upcoming releases.
-
-        // Storing the size of files to fetch in bytes.
-        final long sizeOfSegmentFiles = filesToFetch.stream().mapToLong(file -> file.length()).sum();
-
-        // Maximum size of files to fetch (segment files) in bytes, that can be processed in 1 minute for a m5.xlarge machine.
-        long baseSegmentFilesSize = 100000000;
-
-        // Formula for calculating time needed to process a replication event's files to fetch process
-        final long timeToGetSegmentFiles = 1 + (sizeOfSegmentFiles / baseSegmentFilesSize);
         final GetSegmentFilesRequest request = new GetSegmentFilesRequest(
             replicationId,
             targetAllocationId,
@@ -102,7 +92,7 @@ public void getSegmentFiles(
             checkpoint
         );
         final TransportRequestOptions options = TransportRequestOptions.builder()
-            .withTimeout(TimeValue.timeValueMinutes(timeToGetSegmentFiles))
+            .withTimeout(recoverySettings.internalActionLongTimeout())
             .build();
         transportClient.executeRetryableAction(GET_SEGMENT_FILES, request, options, responseListener, reader);
     }
diff --git a/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationSourceHandler.java b/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationSourceHandler.java
index 750e7629783e7..f9720991338c2 100644
--- a/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationSourceHandler.java
+++ b/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationSourceHandler.java
@@ -159,6 +159,7 @@ public synchronized void sendFiles(GetSegmentFilesRequest request, ActionListene
 
             sendFileStep.whenComplete(r -> {
                 try {
+                    shard.updateVisibleCheckpointForShard(allocationId, copyState.getCheckpoint());
                     future.onResponse(new GetSegmentFilesResponse(List.of(storeFileMetadata)));
                 } finally {
                     IOUtils.close(resources);
diff --git a/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationSourceService.java b/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationSourceService.java
index 91b8243440ac5..247a0cdc0dc58 100644
--- a/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationSourceService.java
+++ b/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationSourceService.java
@@ -14,12 +14,14 @@
 import org.opensearch.action.support.ChannelActionListener;
 import org.opensearch.cluster.ClusterChangedEvent;
 import org.opensearch.cluster.ClusterStateListener;
+import org.opensearch.cluster.metadata.IndexMetadata;
 import org.opensearch.cluster.node.DiscoveryNode;
 import org.opensearch.cluster.routing.ShardRouting;
 import org.opensearch.cluster.service.ClusterService;
 import org.opensearch.common.Nullable;
 import org.opensearch.common.component.AbstractLifecycleComponent;
 import org.opensearch.common.settings.Settings;
+import org.opensearch.index.IndexService;
 import org.opensearch.index.shard.IndexEventListener;
 import org.opensearch.index.shard.IndexShard;
 import org.opensearch.index.shard.ShardId;
@@ -35,6 +37,7 @@
 import org.opensearch.transport.TransportService;
 
 import java.io.IOException;
+import java.util.Set;
 import java.util.concurrent.atomic.AtomicLong;
 
 /**
@@ -162,6 +165,19 @@ public void clusterChanged(ClusterChangedEvent event) {
                 ongoingSegmentReplications.cancelReplication(removedNode);
             }
         }
+        // if a replica for one of the primary shards on this node has closed,
+        // we need to ensure its state has cleared up in ongoing replications.
+        if (event.routingTableChanged()) {
+            for (IndexService indexService : indicesService) {
+                for (IndexShard indexShard : indexService) {
+                    if (indexShard.routingEntry().primary()) {
+                        final IndexMetadata indexMetadata = indexService.getIndexSettings().getIndexMetadata();
+                        final Set<String> inSyncAllocationIds = indexMetadata.inSyncAllocationIds(indexShard.shardId().id());
+                        ongoingSegmentReplications.clearOutOfSyncIds(indexShard.shardId(), inSyncAllocationIds);
+                    }
+                }
+            }
+        }
     }
 
     @Override
diff --git a/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationTarget.java b/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationTarget.java
index 6f46fe8398388..9edafade883be 100644
--- a/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationTarget.java
+++ b/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationTarget.java
@@ -108,7 +108,7 @@ public String description() {
 
     @Override
     public void notifyListener(ReplicationFailedException e, boolean sendShardFailure) {
-        // Cancellations still are passed to our SegmentReplicationListner as failures, if we have failed because of cancellation
+        // Cancellations still are passed to our SegmentReplicationListener as failures, if we have failed because of cancellation
         // update the stage.
         final Throwable cancelledException = ExceptionsHelper.unwrap(e, CancellableThreads.ExecutionCancelledException.class);
         if (cancelledException != null) {
@@ -184,15 +184,20 @@ private void getFiles(CheckpointInfoResponse checkpointInfo, StepListener<GetSeg
          * IllegalStateException to fail the shard
          */
         if (diff.different.isEmpty() == false) {
-            getFilesListener.onFailure(
-                new IllegalStateException(
-                    new ParameterizedMessage(
-                        "Shard {} has local copies of segments that differ from the primary {}",
-                        indexShard.shardId(),
-                        diff.different
-                    ).getFormattedMessage()
-                )
+            IllegalStateException illegalStateException = new IllegalStateException(
+                new ParameterizedMessage(
+                    "Shard {} has local copies of segments that differ from the primary {}",
+                    indexShard.shardId(),
+                    diff.different
+                ).getFormattedMessage()
+            );
+            ReplicationFailedException rfe = new ReplicationFailedException(
+                indexShard.shardId(),
+                "different segment files",
+                illegalStateException
             );
+            fail(rfe, true);
+            throw rfe;
         }
 
         for (StoreFileMetadata file : diff.missing) {
@@ -208,10 +213,10 @@ private void finalizeReplication(CheckpointInfoResponse checkpointInfoResponse,
         ActionListener.completeWith(listener, () -> {
             cancellableThreads.checkForCancel();
             state.setStage(SegmentReplicationState.Stage.FINALIZE_REPLICATION);
-            multiFileWriter.renameAllTempFiles();
-            final Store store = store();
-            store.incRef();
             try {
+                multiFileWriter.renameAllTempFiles();
+                final Store store = store();
+                store.incRef();
                 // Deserialize the new SegmentInfos object sent from the primary.
                 final ReplicationCheckpoint responseCheckpoint = checkpointInfoResponse.getCheckpoint();
                 SegmentInfos infos = SegmentInfos.readCommit(
@@ -220,7 +225,7 @@ private void finalizeReplication(CheckpointInfoResponse checkpointInfoResponse,
                     responseCheckpoint.getSegmentsGen()
                 );
                 cancellableThreads.checkForCancel();
-                indexShard.finalizeReplication(infos, responseCheckpoint.getSeqNo());
+                indexShard.finalizeReplication(infos);
                 store.cleanupAndPreserveLatestCommitPoint("finalize - clean with in memory infos", infos);
             } catch (CorruptIndexException | IndexFormatTooNewException | IndexFormatTooOldException ex) {
                 // this is a fatal exception at this stage.
diff --git a/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationTargetService.java b/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationTargetService.java
index 9cb10a2c9699a..c507bccd0071d 100644
--- a/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationTargetService.java
+++ b/server/src/main/java/org/opensearch/indices/replication/SegmentReplicationTargetService.java
@@ -227,9 +227,10 @@ public synchronized void onNewCheckpoint(final ReplicationCheckpoint receivedChe
                     public void onReplicationDone(SegmentReplicationState state) {
                         logger.trace(
                             () -> new ParameterizedMessage(
-                                "[shardId {}] [replication id {}] Replication complete, timing data: {}",
+                                "[shardId {}] [replication id {}] Replication complete to {}, timing data: {}",
                                 replicaShard.shardId().getId(),
                                 state.getReplicationId(),
+                                replicaShard.getLatestReplicationCheckpoint(),
                                 state.getTimingData()
                             )
                         );
@@ -362,7 +363,7 @@ public void onFailure(Exception e) {
                             completedReplications.put(target.shardId(), target);
                         }
                     } else {
-                        onGoingReplications.fail(replicationId, new ReplicationFailedException("Segment Replication failed", e), true);
+                        onGoingReplications.fail(replicationId, new ReplicationFailedException("Segment Replication failed", e), false);
                     }
                 }
             });
@@ -384,11 +385,21 @@ public void messageReceived(final FileChunkRequest request, TransportChannel cha
         }
     }
 
+    /**
+     * Force sync transport handler forces round of segment replication. Caller should verify necessary checks before
+     * calling this handler.
+     */
     private class ForceSyncTransportRequestHandler implements TransportRequestHandler<ForceSyncRequest> {
         @Override
         public void messageReceived(final ForceSyncRequest request, TransportChannel channel, Task task) throws Exception {
             assert indicesService != null;
             final IndexShard indexShard = indicesService.getShardOrNull(request.getShardId());
+            // Proceed with round of segment replication only when it is allowed
+            if (indexShard.getReplicationEngine().isEmpty()) {
+                logger.info("Ignore force segment replication sync as it is not allowed");
+                channel.sendResponse(TransportResponse.Empty.INSTANCE);
+                return;
+            }
             startReplication(
                 ReplicationCheckpoint.empty(request.getShardId()),
                 indexShard,
@@ -397,9 +408,10 @@ public void messageReceived(final ForceSyncRequest request, TransportChannel cha
                     public void onReplicationDone(SegmentReplicationState state) {
                         logger.trace(
                             () -> new ParameterizedMessage(
-                                "[shardId {}] [replication id {}] Replication complete, timing data: {}",
+                                "[shardId {}] [replication id {}] Replication complete to {}, timing data: {}",
                                 indexShard.shardId().getId(),
                                 state.getReplicationId(),
+                                indexShard.getLatestReplicationCheckpoint(),
                                 state.getTimingData()
                             )
                         );
diff --git a/server/src/main/java/org/opensearch/indices/replication/checkpoint/PublishCheckpointAction.java b/server/src/main/java/org/opensearch/indices/replication/checkpoint/PublishCheckpointAction.java
index 0fd934c31ef7f..9e54b210fea04 100644
--- a/server/src/main/java/org/opensearch/indices/replication/checkpoint/PublishCheckpointAction.java
+++ b/server/src/main/java/org/opensearch/indices/replication/checkpoint/PublishCheckpointAction.java
@@ -13,18 +13,12 @@
 import org.apache.logging.log4j.message.ParameterizedMessage;
 import org.apache.lucene.store.AlreadyClosedException;
 import org.opensearch.ExceptionsHelper;
-import org.opensearch.OpenSearchException;
 import org.opensearch.action.ActionListener;
-import org.opensearch.action.ActionListenerResponseHandler;
 import org.opensearch.action.support.ActionFilters;
-import org.opensearch.action.support.replication.ReplicationMode;
-import org.opensearch.action.support.replication.ReplicationOperation;
 import org.opensearch.action.support.replication.ReplicationResponse;
 import org.opensearch.action.support.replication.ReplicationTask;
 import org.opensearch.action.support.replication.TransportReplicationAction;
 import org.opensearch.cluster.action.shard.ShardStateAction;
-import org.opensearch.cluster.node.DiscoveryNode;
-import org.opensearch.cluster.routing.ShardRouting;
 import org.opensearch.cluster.service.ClusterService;
 import org.opensearch.common.inject.Inject;
 import org.opensearch.common.io.stream.StreamInput;
@@ -33,18 +27,22 @@
 import org.opensearch.index.IndexNotFoundException;
 import org.opensearch.index.shard.IndexShard;
 import org.opensearch.index.shard.IndexShardClosedException;
+import org.opensearch.index.shard.ShardNotInPrimaryModeException;
 import org.opensearch.indices.IndicesService;
 import org.opensearch.indices.replication.SegmentReplicationTargetService;
 import org.opensearch.indices.replication.common.ReplicationTimer;
 import org.opensearch.node.NodeClosedException;
 import org.opensearch.tasks.Task;
 import org.opensearch.threadpool.ThreadPool;
+import org.opensearch.transport.TransportException;
+import org.opensearch.transport.TransportResponseHandler;
 import org.opensearch.transport.TransportService;
 
 import java.io.IOException;
-import java.util.List;
 import java.util.Objects;
 
+import org.opensearch.action.support.replication.ReplicationMode;
+
 /**
  * Replication action responsible for publishing checkpoint to a replica shard.
  *
@@ -109,34 +107,36 @@ public ReplicationMode getReplicationMode(IndexShard indexShard) {
     /**
      * Publish checkpoint request to shard
      */
-    final void publish(IndexShard indexShard) {
+    final void publish(IndexShard indexShard, ReplicationCheckpoint checkpoint) {
+        String primaryAllocationId = indexShard.routingEntry().allocationId().getId();
         long primaryTerm = indexShard.getPendingPrimaryTerm();
         final ThreadContext threadContext = threadPool.getThreadContext();
         try (ThreadContext.StoredContext ignore = threadContext.stashContext()) {
             // we have to execute under the system context so that if security is enabled the sync is authorized
             threadContext.markAsSystemContext();
-            PublishCheckpointRequest request = new PublishCheckpointRequest(indexShard.getLatestReplicationCheckpoint());
-            final ReplicationCheckpoint checkpoint = request.getCheckpoint();
+            PublishCheckpointRequest request = new PublishCheckpointRequest(checkpoint);
+            final ReplicationTask task = (ReplicationTask) taskManager.register("transport", "segrep_publish_checkpoint", request);
+            final ReplicationTimer timer = new ReplicationTimer();
+            timer.start();
+            transportService.sendChildRequest(
+                indexShard.recoveryState().getTargetNode(),
+                transportPrimaryAction,
+                new ConcreteShardRequest<>(request, primaryAllocationId, primaryTerm),
+                task,
+                transportOptions,
+                new TransportResponseHandler<ReplicationResponse>() {
+                    @Override
+                    public ReplicationResponse read(StreamInput in) throws IOException {
+                        return newResponseInstance(in);
+                    }
+
+                    @Override
+                    public String executor() {
+                        return ThreadPool.Names.SAME;
+                    }
 
-            final List<ShardRouting> replicationTargets = indexShard.getReplicationGroup().getReplicationTargets();
-            for (ShardRouting replicationTarget : replicationTargets) {
-                if (replicationTarget.primary()) {
-                    continue;
-                }
-                final DiscoveryNode node = clusterService.state().nodes().get(replicationTarget.currentNodeId());
-                final ConcreteReplicaRequest<PublishCheckpointRequest> replicaRequest = new ConcreteReplicaRequest<>(
-                    request,
-                    replicationTarget.allocationId().getId(),
-                    primaryTerm,
-                    indexShard.getLastKnownGlobalCheckpoint(),
-                    indexShard.getMaxSeqNoOfUpdatesOrDeletes()
-                );
-                final ReplicationTimer timer = new ReplicationTimer();
-                timer.start();
-                final ReplicationTask task = (ReplicationTask) taskManager.register("transport", "segrep_publish_checkpoint", request);
-                ActionListener<ReplicationOperation.ReplicaResponse> listener = new ActionListener<>() {
                     @Override
-                    public void onResponse(ReplicationOperation.ReplicaResponse replicaResponse) {
+                    public void handleResponse(ReplicationResponse response) {
                         timer.stop();
                         logger.trace(
                             () -> new ParameterizedMessage(
@@ -151,22 +151,20 @@ public void onResponse(ReplicationOperation.ReplicaResponse replicaResponse) {
                     }
 
                     @Override
-                    public void onFailure(Exception e) {
+                    public void handleException(TransportException e) {
                         timer.stop();
                         logger.trace("[shardId {}] Failed to publish checkpoint, timing: {}", indexShard.shardId().getId(), timer.time());
                         task.setPhase("finished");
                         taskManager.unregister(task);
-                        if (ExceptionsHelper.unwrap(e, NodeClosedException.class) != null) {
-                            // node shutting down
-                            return;
-                        }
                         if (ExceptionsHelper.unwrap(
                             e,
+                            NodeClosedException.class,
                             IndexNotFoundException.class,
                             AlreadyClosedException.class,
-                            IndexShardClosedException.class
+                            IndexShardClosedException.class,
+                            ShardNotInPrimaryModeException.class
                         ) != null) {
-                            // the index was deleted or the shard is closed
+                            // Node is shutting down or the index was deleted or the shard is closed
                             return;
                         }
                         logger.warn(
@@ -174,13 +172,8 @@ public void onFailure(Exception e) {
                             e
                         );
                     }
-                };
-                final ActionListenerResponseHandler<ReplicaResponse> handler = new ActionListenerResponseHandler<>(
-                    listener,
-                    ReplicaResponse::new
-                );
-                transportService.sendChildRequest(node, transportReplicaAction, replicaRequest, task, transportOptions, handler);
-            }
+                }
+            );
             logger.trace(
                 () -> new ParameterizedMessage(
                     "[shardId {}] Publishing replication checkpoint [{}]",
@@ -197,7 +190,7 @@ protected void shardOperationOnPrimary(
         IndexShard primary,
         ActionListener<PrimaryResult<PublishCheckpointRequest, ReplicationResponse>> listener
     ) {
-        throw new OpenSearchException("PublishCheckpointAction should not hit primary shards");
+        ActionListener.completeWith(listener, () -> new PrimaryResult<>(request, new ReplicationResponse()));
     }
 
     @Override
diff --git a/server/src/main/java/org/opensearch/indices/replication/checkpoint/ReplicationCheckpoint.java b/server/src/main/java/org/opensearch/indices/replication/checkpoint/ReplicationCheckpoint.java
index 6a4e5e449f178..57e667b06a223 100644
--- a/server/src/main/java/org/opensearch/indices/replication/checkpoint/ReplicationCheckpoint.java
+++ b/server/src/main/java/org/opensearch/indices/replication/checkpoint/ReplicationCheckpoint.java
@@ -28,8 +28,8 @@ public class ReplicationCheckpoint implements Writeable, Comparable<ReplicationC
     private final ShardId shardId;
     private final long primaryTerm;
     private final long segmentsGen;
-    private final long seqNo;
     private final long segmentInfosVersion;
+    private final long length;
 
     public static ReplicationCheckpoint empty(ShardId shardId) {
         return new ReplicationCheckpoint(shardId);
@@ -39,24 +39,28 @@ private ReplicationCheckpoint(ShardId shardId) {
         this.shardId = shardId;
         primaryTerm = SequenceNumbers.UNASSIGNED_PRIMARY_TERM;
         segmentsGen = SequenceNumbers.NO_OPS_PERFORMED;
-        seqNo = SequenceNumbers.NO_OPS_PERFORMED;
         segmentInfosVersion = SequenceNumbers.NO_OPS_PERFORMED;
+        length = 0L;
     }
 
-    public ReplicationCheckpoint(ShardId shardId, long primaryTerm, long segmentsGen, long seqNo, long segmentInfosVersion) {
+    public ReplicationCheckpoint(ShardId shardId, long primaryTerm, long segmentsGen, long segmentInfosVersion) {
+        this(shardId, primaryTerm, segmentsGen, segmentInfosVersion, 0L);
+    }
+
+    public ReplicationCheckpoint(ShardId shardId, long primaryTerm, long segmentsGen, long segmentInfosVersion, long length) {
         this.shardId = shardId;
         this.primaryTerm = primaryTerm;
         this.segmentsGen = segmentsGen;
-        this.seqNo = seqNo;
         this.segmentInfosVersion = segmentInfosVersion;
+        this.length = length;
     }
 
     public ReplicationCheckpoint(StreamInput in) throws IOException {
         shardId = new ShardId(in);
         primaryTerm = in.readLong();
         segmentsGen = in.readLong();
-        seqNo = in.readLong();
         segmentInfosVersion = in.readLong();
+        length = in.readLong();
     }
 
     /**
@@ -82,13 +86,6 @@ public long getSegmentInfosVersion() {
         return segmentInfosVersion;
     }
 
-    /**
-     * @return the Seq number
-     */
-    public long getSeqNo() {
-        return seqNo;
-    }
-
     /**
      * Shard Id of primary shard.
      *
@@ -98,13 +95,20 @@ public ShardId getShardId() {
         return shardId;
     }
 
+    /**
+     * @return The size in bytes of this checkpoint.
+     */
+    public long getLength() {
+        return length;
+    }
+
     @Override
     public void writeTo(StreamOutput out) throws IOException {
         shardId.writeTo(out);
         out.writeLong(primaryTerm);
         out.writeLong(segmentsGen);
-        out.writeLong(seqNo);
         out.writeLong(segmentInfosVersion);
+        out.writeLong(length);
     }
 
     @Override
@@ -119,14 +123,13 @@ public boolean equals(Object o) {
         ReplicationCheckpoint that = (ReplicationCheckpoint) o;
         return primaryTerm == that.primaryTerm
             && segmentsGen == that.segmentsGen
-            && seqNo == that.seqNo
             && segmentInfosVersion == that.segmentInfosVersion
             && Objects.equals(shardId, that.shardId);
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(shardId, primaryTerm, segmentsGen, seqNo);
+        return Objects.hash(shardId, primaryTerm, segmentsGen);
     }
 
     /**
@@ -148,10 +151,10 @@ public String toString() {
             + primaryTerm
             + ", segmentsGen="
             + segmentsGen
-            + ", seqNo="
-            + seqNo
             + ", version="
             + segmentInfosVersion
+            + ", size="
+            + length
             + '}';
     }
 }
diff --git a/server/src/main/java/org/opensearch/indices/replication/checkpoint/SegmentReplicationCheckpointPublisher.java b/server/src/main/java/org/opensearch/indices/replication/checkpoint/SegmentReplicationCheckpointPublisher.java
index 6be524cea140e..b4bcdc92e539a 100644
--- a/server/src/main/java/org/opensearch/indices/replication/checkpoint/SegmentReplicationCheckpointPublisher.java
+++ b/server/src/main/java/org/opensearch/indices/replication/checkpoint/SegmentReplicationCheckpointPublisher.java
@@ -32,19 +32,22 @@ public SegmentReplicationCheckpointPublisher(PublishAction publishAction) {
         this.publishAction = Objects.requireNonNull(publishAction);
     }
 
-    public void publish(IndexShard indexShard) {
-        publishAction.publish(indexShard);
+    public void publish(IndexShard indexShard, ReplicationCheckpoint checkpoint) {
+        publishAction.publish(indexShard, checkpoint);
+        indexShard.onCheckpointPublished(checkpoint);
     }
 
     /**
      * Represents an action that is invoked to publish segment replication checkpoint to replica shard
      */
     public interface PublishAction {
-        void publish(IndexShard indexShard);
+        void publish(IndexShard indexShard, ReplicationCheckpoint checkpoint);
     }
 
     /**
      * NoOp Checkpoint publisher
      */
-    public static final SegmentReplicationCheckpointPublisher EMPTY = new SegmentReplicationCheckpointPublisher(indexShard -> {});
+    public static final SegmentReplicationCheckpointPublisher EMPTY = new SegmentReplicationCheckpointPublisher(
+        (indexShard, checkpoint) -> {}
+    );
 }
diff --git a/server/src/main/java/org/opensearch/repositories/fs/FsRepository.java b/server/src/main/java/org/opensearch/repositories/fs/FsRepository.java
index 3b441d32d17fc..0b433a9cfe0a0 100644
--- a/server/src/main/java/org/opensearch/repositories/fs/FsRepository.java
+++ b/server/src/main/java/org/opensearch/repositories/fs/FsRepository.java
@@ -36,6 +36,7 @@
 import org.apache.logging.log4j.Logger;
 import org.opensearch.cluster.metadata.RepositoryMetadata;
 import org.opensearch.cluster.service.ClusterService;
+import org.opensearch.common.Strings;
 import org.opensearch.common.blobstore.BlobPath;
 import org.opensearch.common.blobstore.BlobStore;
 import org.opensearch.common.blobstore.fs.FsBlobStore;
@@ -98,6 +99,9 @@ public class FsRepository extends BlobStoreRepository {
         Property.NodeScope,
         Property.Deprecated
     );
+
+    public static final Setting<String> BASE_PATH_SETTING = Setting.simpleString("base_path");
+
     private final Environment environment;
 
     private ByteSizeValue chunkSize;
@@ -154,7 +158,12 @@ public FsRepository(
         } else {
             this.chunkSize = REPOSITORIES_CHUNK_SIZE_SETTING.get(environment.settings());
         }
-        this.basePath = BlobPath.cleanPath();
+        final String basePath = BASE_PATH_SETTING.get(metadata.settings());
+        if (Strings.hasLength(basePath)) {
+            this.basePath = new BlobPath().add(basePath);
+        } else {
+            this.basePath = BlobPath.cleanPath();
+        }
     }
 
     private static boolean calculateCompress(RepositoryMetadata metadata, Environment environment) {
diff --git a/server/src/main/java/org/opensearch/rest/action/admin/indices/RestGetDataStreamsAction.java b/server/src/main/java/org/opensearch/rest/action/admin/indices/RestGetDataStreamsAction.java
index 3cf27e324a336..4b447d1ac337a 100644
--- a/server/src/main/java/org/opensearch/rest/action/admin/indices/RestGetDataStreamsAction.java
+++ b/server/src/main/java/org/opensearch/rest/action/admin/indices/RestGetDataStreamsAction.java
@@ -55,10 +55,7 @@ public String getName() {
 
     @Override
     public List<Route> routes() {
-        return org.opensearch.common.collect.List.of(
-            new Route(RestRequest.Method.GET, "/_data_stream"),
-            new Route(RestRequest.Method.GET, "/_data_stream/{name}")
-        );
+        return List.of(new Route(RestRequest.Method.GET, "/_data_stream"), new Route(RestRequest.Method.GET, "/_data_stream/{name}"));
     }
 
     @Override
diff --git a/server/src/main/java/org/opensearch/rest/action/admin/indices/RestResolveIndexAction.java b/server/src/main/java/org/opensearch/rest/action/admin/indices/RestResolveIndexAction.java
index 687ff554bd8d4..eee9804abec3b 100644
--- a/server/src/main/java/org/opensearch/rest/action/admin/indices/RestResolveIndexAction.java
+++ b/server/src/main/java/org/opensearch/rest/action/admin/indices/RestResolveIndexAction.java
@@ -57,7 +57,7 @@ public String getName() {
 
     @Override
     public List<Route> routes() {
-        return org.opensearch.common.collect.List.of(new Route(RestRequest.Method.GET, "/_resolve/index/{name}"));
+        return List.of(new Route(RestRequest.Method.GET, "/_resolve/index/{name}"));
     }
 
     @Override
diff --git a/server/src/main/java/org/opensearch/rest/action/admin/indices/RestSimulateIndexTemplateAction.java b/server/src/main/java/org/opensearch/rest/action/admin/indices/RestSimulateIndexTemplateAction.java
index 6edb806007b5e..edb3f12f339ba 100644
--- a/server/src/main/java/org/opensearch/rest/action/admin/indices/RestSimulateIndexTemplateAction.java
+++ b/server/src/main/java/org/opensearch/rest/action/admin/indices/RestSimulateIndexTemplateAction.java
@@ -58,7 +58,7 @@ public class RestSimulateIndexTemplateAction extends BaseRestHandler {
 
     @Override
     public List<Route> routes() {
-        return org.opensearch.common.collect.List.of(new Route(POST, "/_index_template/_simulate_index/{name}"));
+        return List.of(new Route(POST, "/_index_template/_simulate_index/{name}"));
     }
 
     @Override
diff --git a/server/src/main/java/org/opensearch/rest/action/cat/RestCatSegmentReplicationAction.java b/server/src/main/java/org/opensearch/rest/action/cat/RestCatSegmentReplicationAction.java
index 15070c723c2c8..0130f9cd14c36 100644
--- a/server/src/main/java/org/opensearch/rest/action/cat/RestCatSegmentReplicationAction.java
+++ b/server/src/main/java/org/opensearch/rest/action/cat/RestCatSegmentReplicationAction.java
@@ -15,8 +15,11 @@
 import org.opensearch.client.node.NodeClient;
 import org.opensearch.common.Strings;
 import org.opensearch.common.Table;
+import org.opensearch.common.unit.ByteSizeValue;
 import org.opensearch.common.unit.TimeValue;
 import org.opensearch.common.xcontent.XContentOpenSearchExtension;
+import org.opensearch.index.SegmentReplicationPerGroupStats;
+import org.opensearch.index.SegmentReplicationShardStats;
 import org.opensearch.indices.replication.SegmentReplicationState;
 import org.opensearch.rest.BaseRestHandler;
 import org.opensearch.rest.RestHandler;
@@ -24,9 +27,10 @@
 import org.opensearch.rest.RestResponse;
 import org.opensearch.rest.action.RestResponseListener;
 
-import java.util.Comparator;
 import java.util.List;
 import java.util.Locale;
+import java.util.Map;
+import java.util.Set;
 
 import static java.util.Arrays.asList;
 import static java.util.Collections.unmodifiableList;
@@ -67,12 +71,11 @@ public BaseRestHandler.RestChannelConsumer doCatRequest(final RestRequest reques
         segmentReplicationStatsRequest.detailed(request.paramAsBoolean("detailed", false));
         segmentReplicationStatsRequest.shards(Strings.splitStringByCommaToArray(request.param("shards")));
         segmentReplicationStatsRequest.activeOnly(request.paramAsBoolean("active_only", false));
-        segmentReplicationStatsRequest.completedOnly(request.paramAsBoolean("completed_only", false));
         segmentReplicationStatsRequest.indicesOptions(IndicesOptions.fromRequest(request, segmentReplicationStatsRequest.indicesOptions()));
 
         return channel -> client.admin()
             .indices()
-            .segmentReplicationStats(segmentReplicationStatsRequest, new RestResponseListener<SegmentReplicationStatsResponse>(channel) {
+            .segmentReplicationStats(segmentReplicationStatsRequest, new RestResponseListener<>(channel) {
                 @Override
                 public RestResponse buildResponse(final SegmentReplicationStatsResponse response) throws Exception {
                     return RestTable.buildResponse(buildSegmentReplicationTable(request, response), channel);
@@ -90,22 +93,23 @@ protected Table getTableWithHeader(RestRequest request) {
 
         Table t = new Table();
         t.startHeaders()
-            .addCell("index", "alias:i,idx;desc:index name")
             .addCell("shardId", "alias:s;desc: shard Id")
-            .addCell("time", "alias:t,ti;desc:segment replication time")
-            .addCell("stage", "alias:st;desc:segment replication stage")
-            .addCell("source_description", "alias:sdesc;desc:source description")
-            .addCell("target_host", "alias:thost;desc:target host")
             .addCell("target_node", "alias:tnode;desc:target node name")
-            .addCell("files_fetched", "alias:ff;desc:files fetched")
-            .addCell("files_percent", "alias:fp;desc:percent of files fetched")
-            .addCell("bytes_fetched", "alias:bf;desc:bytes fetched")
-            .addCell("bytes_percent", "alias:bp;desc:percent of bytes fetched");
+            .addCell("target_host", "alias:thost;desc:target host")
+            .addCell("checkpoints_behind", "alias:cpb;desc:checkpoints behind primary")
+            .addCell("bytes_behind", "alias:bb;desc:bytes behind primary")
+            .addCell("current_lag", "alias:clag;desc:ongoing time elapsed waiting for replica to catch up to primary")
+            .addCell("last_completed_lag", "alias:lcl;desc:time taken for replica to catch up to latest primary refresh")
+            .addCell("rejected_requests", "alias:rr;desc:count of rejected requests for the replication group");
         if (detailed) {
-            t.addCell("start_time", "alias:start;desc:segment replication start time")
-                .addCell("start_time_millis", "alias:start_millis;desc:segment replication start time in epoch milliseconds")
+            t.addCell("stage", "alias:st;desc:segment replication event stage")
+                .addCell("time", "alias:t,ti;desc:current replication event time")
+                .addCell("files_fetched", "alias:ff;desc:files fetched")
+                .addCell("files_percent", "alias:fp;desc:percent of files fetched")
+                .addCell("bytes_fetched", "alias:bf;desc:bytes fetched")
+                .addCell("bytes_percent", "alias:bp;desc:percent of bytes fetched")
+                .addCell("start_time", "alias:start;desc:segment replication start time")
                 .addCell("stop_time", "alias:stop;desc:segment replication stop time")
-                .addCell("stop_time_millis", "alias:stop_millis;desc:segment replication stop time in epoch milliseconds")
                 .addCell("files", "alias:f;desc:number of files to fetch")
                 .addCell("files_total", "alias:tf;desc:total number of files")
                 .addCell("bytes", "alias:b;desc:number of bytes to fetch")
@@ -135,58 +139,61 @@ public Table buildSegmentReplicationTable(RestRequest request, SegmentReplicatio
         }
         Table t = getTableWithHeader(request);
 
-        for (String index : response.shardSegmentReplicationStates().keySet()) {
+        for (Map.Entry<String, List<SegmentReplicationPerGroupStats>> entry : response.getReplicationStats().entrySet()) {
+            final List<SegmentReplicationPerGroupStats> replicationPerGroupStats = entry.getValue();
 
-            List<SegmentReplicationState> shardSegmentReplicationStates = response.shardSegmentReplicationStates().get(index);
-            if (shardSegmentReplicationStates.size() == 0) {
+            if (replicationPerGroupStats.isEmpty()) {
                 continue;
             }
 
             // Sort ascending by shard id for readability
-            CollectionUtil.introSort(shardSegmentReplicationStates, new Comparator<SegmentReplicationState>() {
-                @Override
-                public int compare(SegmentReplicationState o1, SegmentReplicationState o2) {
-                    int id1 = o1.getShardRouting().shardId().id();
-                    int id2 = o2.getShardRouting().shardId().id();
-                    if (id1 < id2) {
-                        return -1;
-                    } else if (id1 > id2) {
-                        return 1;
-                    } else {
-                        return 0;
-                    }
-                }
+            CollectionUtil.introSort(replicationPerGroupStats, (o1, o2) -> {
+                int id1 = o1.getShardId().id();
+                int id2 = o2.getShardId().id();
+                return Integer.compare(id1, id2);
             });
 
-            for (SegmentReplicationState state : shardSegmentReplicationStates) {
-                t.startRow();
-                t.addCell(index);
-                t.addCell(state.getShardRouting().shardId().id());
-                t.addCell(new TimeValue(state.getTimer().time()));
-                t.addCell(state.getStage().toString().toLowerCase(Locale.ROOT));
-                t.addCell(state.getSourceDescription());
-                t.addCell(state.getTargetNode().getHostName());
-                t.addCell(state.getTargetNode().getName());
-                t.addCell(state.getIndex().recoveredFileCount());
-                t.addCell(String.format(Locale.ROOT, "%1.1f%%", state.getIndex().recoveredFilesPercent()));
-                t.addCell(state.getIndex().recoveredBytes());
-                t.addCell(String.format(Locale.ROOT, "%1.1f%%", state.getIndex().recoveredBytesPercent()));
-                if (detailed) {
-                    t.addCell(XContentOpenSearchExtension.DEFAULT_DATE_PRINTER.print(state.getTimer().startTime()));
-                    t.addCell(state.getTimer().startTime());
-                    t.addCell(XContentOpenSearchExtension.DEFAULT_DATE_PRINTER.print(state.getTimer().stopTime()));
-                    t.addCell(state.getTimer().stopTime());
-                    t.addCell(state.getIndex().totalRecoverFiles());
-                    t.addCell(state.getIndex().totalFileCount());
-                    t.addCell(state.getIndex().totalRecoverBytes());
-                    t.addCell(state.getIndex().totalBytes());
-                    t.addCell(state.getReplicatingStageTime());
-                    t.addCell(state.getGetCheckpointInfoStageTime());
-                    t.addCell(state.getFileDiffStageTime());
-                    t.addCell(state.getGetFileStageTime());
-                    t.addCell(state.getFinalizeReplicationStageTime());
+            for (SegmentReplicationPerGroupStats perGroupStats : replicationPerGroupStats) {
+
+                final Set<SegmentReplicationShardStats> replicaShardStats = perGroupStats.getReplicaStats();
+
+                for (SegmentReplicationShardStats shardStats : replicaShardStats) {
+                    final SegmentReplicationState state = shardStats.getCurrentReplicationState();
+                    if (state == null) {
+                        continue;
+                    }
+
+                    t.startRow();
+                    t.addCell(perGroupStats.getShardId());
+                    // these nulls should never happen, here for safety.
+                    t.addCell(state.getTargetNode().getName());
+                    t.addCell(state.getTargetNode().getHostName());
+                    t.addCell(shardStats.getCheckpointsBehindCount());
+                    t.addCell(new ByteSizeValue(shardStats.getBytesBehindCount()));
+                    t.addCell(new TimeValue(shardStats.getCurrentReplicationTimeMillis()));
+                    t.addCell(new TimeValue(shardStats.getLastCompletedReplicationTimeMillis()));
+                    t.addCell(perGroupStats.getRejectedRequestCount());
+                    if (detailed) {
+                        t.addCell(state.getStage().toString().toLowerCase(Locale.ROOT));
+                        t.addCell(new TimeValue(state.getTimer().time()));
+                        t.addCell(state.getIndex().recoveredFileCount());
+                        t.addCell(String.format(Locale.ROOT, "%1.1f%%", state.getIndex().recoveredFilesPercent()));
+                        t.addCell(state.getIndex().recoveredBytes());
+                        t.addCell(String.format(Locale.ROOT, "%1.1f%%", state.getIndex().recoveredBytesPercent()));
+                        t.addCell(XContentOpenSearchExtension.DEFAULT_DATE_PRINTER.print(state.getTimer().startTime()));
+                        t.addCell(XContentOpenSearchExtension.DEFAULT_DATE_PRINTER.print(state.getTimer().stopTime()));
+                        t.addCell(state.getIndex().totalRecoverFiles());
+                        t.addCell(state.getIndex().totalFileCount());
+                        t.addCell(new ByteSizeValue(state.getIndex().totalRecoverBytes()));
+                        t.addCell(new ByteSizeValue(state.getIndex().totalBytes()));
+                        t.addCell(state.getReplicatingStageTime());
+                        t.addCell(state.getGetCheckpointInfoStageTime());
+                        t.addCell(state.getFileDiffStageTime());
+                        t.addCell(state.getGetFileStageTime());
+                        t.addCell(state.getFinalizeReplicationStageTime());
+                    }
+                    t.endRow();
                 }
-                t.endRow();
             }
         }
 
diff --git a/server/src/main/java/org/opensearch/script/AbstractSortScript.java b/server/src/main/java/org/opensearch/script/AbstractSortScript.java
index c72717f8bc927..ac39be1074efa 100644
--- a/server/src/main/java/org/opensearch/script/AbstractSortScript.java
+++ b/server/src/main/java/org/opensearch/script/AbstractSortScript.java
@@ -54,7 +54,7 @@
 abstract class AbstractSortScript implements ScorerAware {
 
     private static final DeprecationLogger deprecationLogger = DeprecationLogger.getLogger(DynamicMap.class);
-    private static final Map<String, Function<Object, Object>> PARAMS_FUNCTIONS = org.opensearch.common.collect.Map.of("doc", value -> {
+    private static final Map<String, Function<Object, Object>> PARAMS_FUNCTIONS = Map.of("doc", value -> {
         deprecationLogger.deprecate(
             "sort-script_doc",
             "Accessing variable [doc] via [params.doc] from within an sort-script " + "is deprecated in favor of directly accessing [doc]."
diff --git a/server/src/main/java/org/opensearch/script/AggregationScript.java b/server/src/main/java/org/opensearch/script/AggregationScript.java
index 4c9d6060ddbfd..ef300e9473d3e 100644
--- a/server/src/main/java/org/opensearch/script/AggregationScript.java
+++ b/server/src/main/java/org/opensearch/script/AggregationScript.java
@@ -58,7 +58,7 @@ public abstract class AggregationScript implements ScorerAware {
     public static final ScriptContext<Factory> CONTEXT = new ScriptContext<>("aggs", Factory.class);
 
     private static final DeprecationLogger deprecationLogger = DeprecationLogger.getLogger(DynamicMap.class);
-    private static final Map<String, Function<Object, Object>> PARAMS_FUNCTIONS = org.opensearch.common.collect.Map.of("doc", value -> {
+    private static final Map<String, Function<Object, Object>> PARAMS_FUNCTIONS = Map.of("doc", value -> {
         deprecationLogger.deprecate(
             "aggregation-script_doc",
             "Accessing variable [doc] via [params.doc] from within an aggregation-script "
diff --git a/server/src/main/java/org/opensearch/script/FieldScript.java b/server/src/main/java/org/opensearch/script/FieldScript.java
index 531616a74dce9..82b5c9a088a2c 100644
--- a/server/src/main/java/org/opensearch/script/FieldScript.java
+++ b/server/src/main/java/org/opensearch/script/FieldScript.java
@@ -54,7 +54,7 @@ public abstract class FieldScript {
     public static final String[] PARAMETERS = {};
 
     private static final DeprecationLogger deprecationLogger = DeprecationLogger.getLogger(DynamicMap.class);
-    private static final Map<String, Function<Object, Object>> PARAMS_FUNCTIONS = org.opensearch.common.collect.Map.of("doc", value -> {
+    private static final Map<String, Function<Object, Object>> PARAMS_FUNCTIONS = Map.of("doc", value -> {
         deprecationLogger.deprecate(
             "field-script_doc",
             "Accessing variable [doc] via [params.doc] from within an field-script " + "is deprecated in favor of directly accessing [doc]."
diff --git a/server/src/main/java/org/opensearch/script/ScoreScript.java b/server/src/main/java/org/opensearch/script/ScoreScript.java
index dba44995b18f0..5c6553ffc2a28 100644
--- a/server/src/main/java/org/opensearch/script/ScoreScript.java
+++ b/server/src/main/java/org/opensearch/script/ScoreScript.java
@@ -84,7 +84,7 @@ public Explanation get(double score, Explanation subQueryExplanation) {
     }
 
     private static final DeprecationLogger deprecationLogger = DeprecationLogger.getLogger(DynamicMap.class);
-    private static final Map<String, Function<Object, Object>> PARAMS_FUNCTIONS = org.opensearch.common.collect.Map.of("doc", value -> {
+    private static final Map<String, Function<Object, Object>> PARAMS_FUNCTIONS = Map.of("doc", value -> {
         deprecationLogger.deprecate(
             "score-script_doc",
             "Accessing variable [doc] via [params.doc] from within an score-script " + "is deprecated in favor of directly accessing [doc]."
diff --git a/server/src/main/java/org/opensearch/script/ScriptedMetricAggContexts.java b/server/src/main/java/org/opensearch/script/ScriptedMetricAggContexts.java
index 58d0f7b4f6040..2f61fd75471ad 100644
--- a/server/src/main/java/org/opensearch/script/ScriptedMetricAggContexts.java
+++ b/server/src/main/java/org/opensearch/script/ScriptedMetricAggContexts.java
@@ -99,7 +99,7 @@ public interface Factory extends ScriptFactory {
     public abstract static class MapScript {
 
         private static final DeprecationLogger deprecationLogger = DeprecationLogger.getLogger(DynamicMap.class);
-        private static final Map<String, Function<Object, Object>> PARAMS_FUNCTIONS = org.opensearch.common.collect.Map.of("doc", value -> {
+        private static final Map<String, Function<Object, Object>> PARAMS_FUNCTIONS = Map.of("doc", value -> {
             deprecationLogger.deprecate(
                 "map-script_doc",
                 "Accessing variable [doc] via [params.doc] from within an scripted metric agg map script "
diff --git a/server/src/main/java/org/opensearch/script/TermsSetQueryScript.java b/server/src/main/java/org/opensearch/script/TermsSetQueryScript.java
index 02e361b0f5415..99fa2d584ebfd 100644
--- a/server/src/main/java/org/opensearch/script/TermsSetQueryScript.java
+++ b/server/src/main/java/org/opensearch/script/TermsSetQueryScript.java
@@ -55,7 +55,7 @@ public abstract class TermsSetQueryScript {
     public static final ScriptContext<Factory> CONTEXT = new ScriptContext<>("terms_set", Factory.class);
 
     private static final DeprecationLogger deprecationLogger = DeprecationLogger.getLogger(DynamicMap.class);
-    private static final Map<String, Function<Object, Object>> PARAMS_FUNCTIONS = org.opensearch.common.collect.Map.of("doc", value -> {
+    private static final Map<String, Function<Object, Object>> PARAMS_FUNCTIONS = Map.of("doc", value -> {
         deprecationLogger.deprecate(
             "terms-set-query-script_doc",
             "Accessing variable [doc] via [params.doc] from within an terms-set-query-script "
diff --git a/server/src/main/java/org/opensearch/search/DocValueFormat.java b/server/src/main/java/org/opensearch/search/DocValueFormat.java
index 84c46e400543a..07ff5405211ff 100644
--- a/server/src/main/java/org/opensearch/search/DocValueFormat.java
+++ b/server/src/main/java/org/opensearch/search/DocValueFormat.java
@@ -302,6 +302,27 @@ public double parseDouble(String value, boolean roundUp, LongSupplier now) {
         public String toString() {
             return "DocValueFormat.DateTime(" + formatter + ", " + timeZone + ", " + resolution + ")";
         }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) {
+                return true;
+            }
+            if (o == null || getClass() != o.getClass()) {
+                return false;
+            }
+
+            DateTime that = (DateTime) o;
+
+            return Objects.equals(formatter, that.formatter)
+                && Objects.equals(timeZone, that.timeZone)
+                && Objects.equals(resolution, that.resolution);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(formatter, timeZone, resolution);
+        }
     }
 
     DocValueFormat GEOHASH = new DocValueFormat() {
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/DateHistogramValuesSourceBuilder.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/DateHistogramValuesSourceBuilder.java
index 1d3a96e66885b..2fb3ea094b0ab 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/DateHistogramValuesSourceBuilder.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/DateHistogramValuesSourceBuilder.java
@@ -63,6 +63,7 @@
 import java.io.IOException;
 import java.time.ZoneId;
 import java.time.ZoneOffset;
+import java.util.List;
 import java.util.Objects;
 import java.util.function.LongConsumer;
 
@@ -296,7 +297,7 @@ public DateHistogramValuesSourceBuilder offset(long offset) {
     public static void register(ValuesSourceRegistry.Builder builder) {
         builder.register(
             REGISTRY_KEY,
-            org.opensearch.common.collect.List.of(CoreValuesSourceType.DATE, CoreValuesSourceType.NUMERIC),
+            List.of(CoreValuesSourceType.DATE, CoreValuesSourceType.NUMERIC),
             (valuesSourceConfig, rounding, name, hasScript, format, missingBucket, missingOrder, order) -> {
                 ValuesSource.Numeric numeric = (ValuesSource.Numeric) valuesSourceConfig.getValuesSource();
                 // TODO once composite is plugged in to the values source registry or at least understands Date values source types use it
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/DoubleValuesSource.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/DoubleValuesSource.java
index d05c78f540641..970f07b6a9d74 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/DoubleValuesSource.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/DoubleValuesSource.java
@@ -152,11 +152,9 @@ void setAfter(Comparable value) {
         } else if (value instanceof Number) {
             afterValue = ((Number) value).doubleValue();
         } else {
-            afterValue = format.parseDouble(
-                value.toString(),
-                false,
-                () -> { throw new IllegalArgumentException("now() is not supported in [after] key"); }
-            );
+            afterValue = format.parseDouble(value.toString(), false, () -> {
+                throw new IllegalArgumentException("now() is not supported in [after] key");
+            });
         }
     }
 
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/HistogramValuesSourceBuilder.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/HistogramValuesSourceBuilder.java
index 7f1393f7c8fb2..05eba71bbdbd5 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/HistogramValuesSourceBuilder.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/HistogramValuesSourceBuilder.java
@@ -51,6 +51,7 @@
 import org.opensearch.search.sort.SortOrder;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Objects;
 import java.util.function.LongConsumer;
 
@@ -100,7 +101,7 @@ static HistogramValuesSourceBuilder parse(String name, XContentParser parser) th
     public static void register(ValuesSourceRegistry.Builder builder) {
         builder.register(
             REGISTRY_KEY,
-            org.opensearch.common.collect.List.of(CoreValuesSourceType.DATE, CoreValuesSourceType.NUMERIC),
+            List.of(CoreValuesSourceType.DATE, CoreValuesSourceType.NUMERIC),
             (valuesSourceConfig, interval, name, hasScript, format, missingBucket, missingOrder, order) -> {
                 ValuesSource.Numeric numeric = (ValuesSource.Numeric) valuesSourceConfig.getValuesSource();
                 final HistogramValuesSource vs = new HistogramValuesSource(numeric, interval);
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/LongValuesSource.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/LongValuesSource.java
index ec6410c2a9377..8f0e99b187c2d 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/LongValuesSource.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/LongValuesSource.java
@@ -170,11 +170,9 @@ protected void setAfter(Comparable value) {
             afterValue = null;
         } else {
             // parse the value from a string in case it is a date or a formatted unsigned long.
-            afterValue = format.parseLong(
-                value.toString(),
-                false,
-                () -> { throw new IllegalArgumentException("now() is not supported in [after] key"); }
-            );
+            afterValue = format.parseLong(value.toString(), false, () -> {
+                throw new IllegalArgumentException("now() is not supported in [after] key");
+            });
         }
     }
 
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/TermsValuesSourceBuilder.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/TermsValuesSourceBuilder.java
index 64b2635ea7fee..c87c5eef157fa 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/TermsValuesSourceBuilder.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/composite/TermsValuesSourceBuilder.java
@@ -52,6 +52,7 @@
 import org.opensearch.search.sort.SortOrder;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.function.LongConsumer;
 import java.util.function.LongUnaryOperator;
 
@@ -118,7 +119,7 @@ public String type() {
     static void register(ValuesSourceRegistry.Builder builder) {
         builder.register(
             REGISTRY_KEY,
-            org.opensearch.common.collect.List.of(CoreValuesSourceType.DATE, CoreValuesSourceType.NUMERIC, CoreValuesSourceType.BOOLEAN),
+            List.of(CoreValuesSourceType.DATE, CoreValuesSourceType.NUMERIC, CoreValuesSourceType.BOOLEAN),
             (valuesSourceConfig, name, hasScript, format, missingBucket, missingOrder, order) -> {
                 final DocValueFormat docValueFormat;
                 if (format == null && valuesSourceConfig.valueSourceType() == CoreValuesSourceType.DATE) {
@@ -180,7 +181,7 @@ static void register(ValuesSourceRegistry.Builder builder) {
 
         builder.register(
             REGISTRY_KEY,
-            org.opensearch.common.collect.List.of(CoreValuesSourceType.BYTES, CoreValuesSourceType.IP),
+            List.of(CoreValuesSourceType.BYTES, CoreValuesSourceType.IP),
             (valuesSourceConfig, name, hasScript, format, missingBucket, missingOrder, order) -> new CompositeValuesSourceConfig(
                 name,
                 valuesSourceConfig.fieldType(),
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregator.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregator.java
index 295dfec639de6..040621ce8ec34 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregator.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregator.java
@@ -162,34 +162,29 @@ public void collect(int doc, long owningBucketOrd) throws IOException {
 
     @Override
     public InternalAggregation[] buildAggregations(long[] owningBucketOrds) throws IOException {
-        return buildAggregationsForVariableBuckets(
-            owningBucketOrds,
-            bucketOrds,
-            (bucketValue, docCount, subAggregationResults) -> {
-                return new InternalDateHistogram.Bucket(bucketValue, docCount, keyed, formatter, subAggregationResults);
-            },
-            (owningBucketOrd, buckets) -> {
-                // the contract of the histogram aggregation is that shards must return buckets ordered by key in ascending order
-                CollectionUtil.introSort(buckets, BucketOrder.key(true).comparator());
-
-                // value source will be null for unmapped fields
-                // Important: use `rounding` here, not `shardRounding`
-                InternalDateHistogram.EmptyBucketInfo emptyBucketInfo = minDocCount == 0
-                    ? new InternalDateHistogram.EmptyBucketInfo(rounding.withoutOffset(), buildEmptySubAggregations(), extendedBounds)
-                    : null;
-                return new InternalDateHistogram(
-                    name,
-                    buckets,
-                    order,
-                    minDocCount,
-                    rounding.offset(),
-                    emptyBucketInfo,
-                    formatter,
-                    keyed,
-                    metadata()
-                );
-            }
-        );
+        return buildAggregationsForVariableBuckets(owningBucketOrds, bucketOrds, (bucketValue, docCount, subAggregationResults) -> {
+            return new InternalDateHistogram.Bucket(bucketValue, docCount, keyed, formatter, subAggregationResults);
+        }, (owningBucketOrd, buckets) -> {
+            // the contract of the histogram aggregation is that shards must return buckets ordered by key in ascending order
+            CollectionUtil.introSort(buckets, BucketOrder.key(true).comparator());
+
+            // value source will be null for unmapped fields
+            // Important: use `rounding` here, not `shardRounding`
+            InternalDateHistogram.EmptyBucketInfo emptyBucketInfo = minDocCount == 0
+                ? new InternalDateHistogram.EmptyBucketInfo(rounding.withoutOffset(), buildEmptySubAggregations(), extendedBounds)
+                : null;
+            return new InternalDateHistogram(
+                name,
+                buckets,
+                order,
+                minDocCount,
+                rounding.offset(),
+                emptyBucketInfo,
+                formatter,
+                keyed,
+                metadata()
+            );
+        });
     }
 
     @Override
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregatorFactory.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregatorFactory.java
index eb22a857643c4..dd74d83c665de 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregatorFactory.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregatorFactory.java
@@ -33,7 +33,6 @@
 package org.opensearch.search.aggregations.bucket.histogram;
 
 import org.opensearch.common.Rounding;
-import org.opensearch.common.collect.List;
 import org.opensearch.index.query.QueryShardContext;
 import org.opensearch.search.aggregations.Aggregator;
 import org.opensearch.search.aggregations.AggregatorFactories;
@@ -47,6 +46,7 @@
 import org.opensearch.search.internal.SearchContext;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Map;
 
 /**
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/HistogramAggregatorFactory.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/HistogramAggregatorFactory.java
index 722bf87201631..321c16cdba970 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/HistogramAggregatorFactory.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/HistogramAggregatorFactory.java
@@ -32,7 +32,6 @@
 
 package org.opensearch.search.aggregations.bucket.histogram;
 
-import org.opensearch.common.collect.List;
 import org.opensearch.index.query.QueryShardContext;
 import org.opensearch.search.aggregations.Aggregator;
 import org.opensearch.search.aggregations.AggregatorFactories;
@@ -46,6 +45,7 @@
 import org.opensearch.search.internal.SearchContext;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Map;
 
 /**
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/InternalAutoDateHistogram.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/InternalAutoDateHistogram.java
index a91ddf2e64879..fdf047c13480a 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/InternalAutoDateHistogram.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/histogram/InternalAutoDateHistogram.java
@@ -482,10 +482,7 @@ private BucketReduceResult addEmptyBuckets(BucketReduceResult current, ReduceCon
 
         Bucket lastBucket = null;
         ListIterator<Bucket> iter = list.listIterator();
-        InternalAggregations reducedEmptySubAggs = InternalAggregations.reduce(
-            org.opensearch.common.collect.List.of(bucketInfo.emptySubAggregations),
-            reduceContext
-        );
+        InternalAggregations reducedEmptySubAggs = InternalAggregations.reduce(List.of(bucketInfo.emptySubAggregations), reduceContext);
 
         // Add the empty buckets within the data,
         // e.g. if the data series is [1,2,3,7] there're 3 empty buckets that will be created for 4,5,6
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/range/AbstractRangeAggregatorFactory.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/range/AbstractRangeAggregatorFactory.java
index 90ae2e994caf1..bfd7845e7e16f 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/range/AbstractRangeAggregatorFactory.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/range/AbstractRangeAggregatorFactory.java
@@ -47,6 +47,7 @@
 import org.opensearch.search.internal.SearchContext;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -67,7 +68,7 @@ public static void registerAggregators(
     ) {
         builder.register(
             registryKey,
-            org.opensearch.common.collect.List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
+            List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
             RangeAggregator::new,
             true
         );
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/sampler/DiversifiedAggregatorFactory.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/sampler/DiversifiedAggregatorFactory.java
index f8d3040620a51..41ef823a375c0 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/sampler/DiversifiedAggregatorFactory.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/sampler/DiversifiedAggregatorFactory.java
@@ -47,6 +47,7 @@
 import org.opensearch.search.internal.SearchContext;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -59,7 +60,7 @@ public class DiversifiedAggregatorFactory extends ValuesSourceAggregatorFactory
     public static void registerAggregators(ValuesSourceRegistry.Builder builder) {
         builder.register(
             DiversifiedAggregationBuilder.REGISTRY_KEY,
-            org.opensearch.common.collect.List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
+            List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
             (
                 String name,
                 int shardSize,
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregationFactory.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregationFactory.java
index 8a061c0fbf512..01975381f15a4 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregationFactory.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregationFactory.java
@@ -50,21 +50,14 @@ public class MultiTermsAggregationFactory extends AggregatorFactory {
     private final boolean showTermDocCountError;
 
     public static void registerAggregators(ValuesSourceRegistry.Builder builder) {
-        builder.register(
-            REGISTRY_KEY,
-            org.opensearch.common.collect.List.of(CoreValuesSourceType.BYTES, CoreValuesSourceType.IP),
-            config -> {
-                final IncludeExclude.StringFilter filter = config.v2() == null
-                    ? null
-                    : config.v2().convertToStringFilter(config.v1().format());
-                return MultiTermsAggregator.InternalValuesSourceFactory.bytesValuesSource(config.v1().getValuesSource(), filter);
-            },
-            true
-        );
+        builder.register(REGISTRY_KEY, List.of(CoreValuesSourceType.BYTES, CoreValuesSourceType.IP), config -> {
+            final IncludeExclude.StringFilter filter = config.v2() == null ? null : config.v2().convertToStringFilter(config.v1().format());
+            return MultiTermsAggregator.InternalValuesSourceFactory.bytesValuesSource(config.v1().getValuesSource(), filter);
+        }, true);
 
         builder.register(
             REGISTRY_KEY,
-            org.opensearch.common.collect.List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.BOOLEAN, CoreValuesSourceType.DATE),
+            List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.BOOLEAN, CoreValuesSourceType.DATE),
             config -> {
                 ValuesSourceConfig valuesSourceConfig = config.v1();
                 IncludeExclude includeExclude = config.v2();
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregator.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregator.java
index 45898a689a605..c21bfd6fb73b9 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregator.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregator.java
@@ -188,7 +188,7 @@ InternalMultiTerms buildResult(long owningBucketOrd, long otherDocCount, Interna
             otherDocCount,
             0,
             formats,
-            org.opensearch.common.collect.List.of(topBuckets)
+            List.of(topBuckets)
         );
     }
 
@@ -341,7 +341,7 @@ private void apply(
                     List<List<Object>> results
                 ) throws IOException {
                     if (index == collectedValues.size()) {
-                        results.add(org.opensearch.common.collect.List.copyOf(current));
+                        results.add(List.copyOf(current));
                     } else if (null != collectedValues.get(index)) {
                         for (Object value : collectedValues.get(index).get()) {
                             current.add(value);
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/NumericTermsAggregator.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/NumericTermsAggregator.java
index 2c4c502b86695..70e98c0d19cd7 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/NumericTermsAggregator.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/NumericTermsAggregator.java
@@ -37,7 +37,6 @@
 import org.apache.lucene.search.ScoreMode;
 import org.apache.lucene.util.NumericUtils;
 import org.apache.lucene.util.PriorityQueue;
-import org.opensearch.common.collect.List;
 import org.opensearch.common.lease.Releasable;
 import org.opensearch.common.lease.Releasables;
 import org.opensearch.common.util.LongArray;
@@ -62,6 +61,7 @@
 
 import java.io.IOException;
 import java.util.Arrays;
+import java.util.List;
 import java.util.Map;
 import java.util.function.BiConsumer;
 import java.util.function.Function;
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/TermsAggregatorFactory.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/TermsAggregatorFactory.java
index 50b1ae001db97..ad57a07a4a8f5 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/TermsAggregatorFactory.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/TermsAggregatorFactory.java
@@ -444,7 +444,7 @@ Aggregator create(
                     && ordinalsValuesSource.supportsGlobalOrdinalsMapping()
                     &&
                 // we use the static COLLECT_SEGMENT_ORDS to allow tests to force specific optimizations
-                (COLLECT_SEGMENT_ORDS != null ? COLLECT_SEGMENT_ORDS.booleanValue() : ratio <= 0.5 && maxOrd <= 2048)) {
+                    (COLLECT_SEGMENT_ORDS != null ? COLLECT_SEGMENT_ORDS.booleanValue() : ratio <= 0.5 && maxOrd <= 2048)) {
                     /*
                      * We can use the low cardinality execution mode iff this aggregator:
                      *  - has no sub-aggregator AND
diff --git a/server/src/main/java/org/opensearch/search/aggregations/metrics/AvgAggregatorFactory.java b/server/src/main/java/org/opensearch/search/aggregations/metrics/AvgAggregatorFactory.java
index 727304f8a5254..75419b7c64b12 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/metrics/AvgAggregatorFactory.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/metrics/AvgAggregatorFactory.java
@@ -44,6 +44,7 @@
 import org.opensearch.search.internal.SearchContext;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -67,7 +68,7 @@ class AvgAggregatorFactory extends ValuesSourceAggregatorFactory {
     static void registerAggregators(ValuesSourceRegistry.Builder builder) {
         builder.register(
             AvgAggregationBuilder.REGISTRY_KEY,
-            org.opensearch.common.collect.List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
+            List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
             AvgAggregator::new,
             true
         );
diff --git a/server/src/main/java/org/opensearch/search/aggregations/metrics/MaxAggregatorFactory.java b/server/src/main/java/org/opensearch/search/aggregations/metrics/MaxAggregatorFactory.java
index 3ec24ad04d9aa..96f1af94f2d07 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/metrics/MaxAggregatorFactory.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/metrics/MaxAggregatorFactory.java
@@ -44,6 +44,7 @@
 import org.opensearch.search.internal.SearchContext;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -56,7 +57,7 @@ class MaxAggregatorFactory extends ValuesSourceAggregatorFactory {
     static void registerAggregators(ValuesSourceRegistry.Builder builder) {
         builder.register(
             MaxAggregationBuilder.REGISTRY_KEY,
-            org.opensearch.common.collect.List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
+            List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
             MaxAggregator::new,
             true
         );
diff --git a/server/src/main/java/org/opensearch/search/aggregations/metrics/MinAggregatorFactory.java b/server/src/main/java/org/opensearch/search/aggregations/metrics/MinAggregatorFactory.java
index 1b24b88d6f068..b117f70c81baf 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/metrics/MinAggregatorFactory.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/metrics/MinAggregatorFactory.java
@@ -44,6 +44,7 @@
 import org.opensearch.search.internal.SearchContext;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -56,7 +57,7 @@ class MinAggregatorFactory extends ValuesSourceAggregatorFactory {
     static void registerAggregators(ValuesSourceRegistry.Builder builder) {
         builder.register(
             MinAggregationBuilder.REGISTRY_KEY,
-            org.opensearch.common.collect.List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
+            List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
             MinAggregator::new,
             true
         );
diff --git a/server/src/main/java/org/opensearch/search/aggregations/metrics/ScriptedMetricAggregatorFactory.java b/server/src/main/java/org/opensearch/search/aggregations/metrics/ScriptedMetricAggregatorFactory.java
index 7b5848fc79197..5c831d60f75a8 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/metrics/ScriptedMetricAggregatorFactory.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/metrics/ScriptedMetricAggregatorFactory.java
@@ -103,7 +103,7 @@ public Aggregator createInternal(
         CardinalityUpperBound cardinality,
         Map<String, Object> metadata
     ) throws IOException {
-        Map<String, Object> aggParams = this.aggParams == null ? org.opensearch.common.collect.Map.of() : this.aggParams;
+        Map<String, Object> aggParams = this.aggParams == null ? Map.of() : this.aggParams;
 
         Script reduceScript = deepCopyScript(this.reduceScript, searchContext, aggParams);
 
diff --git a/server/src/main/java/org/opensearch/search/aggregations/metrics/StatsAggregatorFactory.java b/server/src/main/java/org/opensearch/search/aggregations/metrics/StatsAggregatorFactory.java
index 6e343ed9a31d1..0c10df174efa0 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/metrics/StatsAggregatorFactory.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/metrics/StatsAggregatorFactory.java
@@ -44,6 +44,7 @@
 import org.opensearch.search.internal.SearchContext;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -67,7 +68,7 @@ class StatsAggregatorFactory extends ValuesSourceAggregatorFactory {
     static void registerAggregators(ValuesSourceRegistry.Builder builder) {
         builder.register(
             StatsAggregationBuilder.REGISTRY_KEY,
-            org.opensearch.common.collect.List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
+            List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
             StatsAggregator::new,
             true
         );
diff --git a/server/src/main/java/org/opensearch/search/aggregations/metrics/SumAggregatorFactory.java b/server/src/main/java/org/opensearch/search/aggregations/metrics/SumAggregatorFactory.java
index c94949bca09e6..b3506ff958833 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/metrics/SumAggregatorFactory.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/metrics/SumAggregatorFactory.java
@@ -44,6 +44,7 @@
 import org.opensearch.search.internal.SearchContext;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -67,7 +68,7 @@ class SumAggregatorFactory extends ValuesSourceAggregatorFactory {
     static void registerAggregators(ValuesSourceRegistry.Builder builder) {
         builder.register(
             SumAggregationBuilder.REGISTRY_KEY,
-            org.opensearch.common.collect.List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
+            List.of(CoreValuesSourceType.NUMERIC, CoreValuesSourceType.DATE, CoreValuesSourceType.BOOLEAN),
             SumAggregator::new,
             true
         );
diff --git a/server/src/main/java/org/opensearch/search/aggregations/pipeline/DerivativePipelineAggregator.java b/server/src/main/java/org/opensearch/search/aggregations/pipeline/DerivativePipelineAggregator.java
index 3603d1c5a0c58..fd9caf59d9e01 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/pipeline/DerivativePipelineAggregator.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/pipeline/DerivativePipelineAggregator.java
@@ -120,9 +120,9 @@ public InternalAggregation reduce(InternalAggregation aggregation, ReduceContext
                 if (xAxisUnits != null) {
                     xDiff = (thisBucketKey.doubleValue() - lastBucketKey.doubleValue()) / xAxisUnits;
                 }
-                final List<InternalAggregation> aggs = StreamSupport.stream(bucket.getAggregations().spliterator(), false)
-                    .map((p) -> { return (InternalAggregation) p; })
-                    .collect(Collectors.toList());
+                final List<InternalAggregation> aggs = StreamSupport.stream(bucket.getAggregations().spliterator(), false).map((p) -> {
+                    return (InternalAggregation) p;
+                }).collect(Collectors.toList());
                 aggs.add(new InternalDerivative(name(), gradient, xDiff, formatter, metadata()));
                 Bucket newBucket = factory.createBucket(factory.getKey(bucket), bucket.getDocCount(), InternalAggregations.from(aggs));
                 newBuckets.add(newBucket);
diff --git a/server/src/main/java/org/opensearch/search/fetch/subphase/FetchFieldsPhase.java b/server/src/main/java/org/opensearch/search/fetch/subphase/FetchFieldsPhase.java
index 0b15124f08cee..9988abb778bce 100644
--- a/server/src/main/java/org/opensearch/search/fetch/subphase/FetchFieldsPhase.java
+++ b/server/src/main/java/org/opensearch/search/fetch/subphase/FetchFieldsPhase.java
@@ -96,7 +96,7 @@ public void process(HitContext hitContext) throws IOException {
     private Set<String> getIgnoredFields(SearchHit hit) {
         DocumentField field = hit.field(IgnoredFieldMapper.NAME);
         if (field == null) {
-            return org.opensearch.common.collect.Set.of();
+            return Set.of();
         }
 
         Set<String> ignoredFields = new HashSet<>();
diff --git a/server/src/main/java/org/opensearch/search/profile/ProfileResult.java b/server/src/main/java/org/opensearch/search/profile/ProfileResult.java
index c05c574b77942..82b060fb421f8 100644
--- a/server/src/main/java/org/opensearch/search/profile/ProfileResult.java
+++ b/server/src/main/java/org/opensearch/search/profile/ProfileResult.java
@@ -91,8 +91,8 @@ public ProfileResult(
         this.type = type;
         this.description = description;
         this.breakdown = Objects.requireNonNull(breakdown, "required breakdown argument missing");
-        this.debug = debug == null ? org.opensearch.common.collect.Map.of() : debug;
-        this.children = children == null ? org.opensearch.common.collect.List.of() : children;
+        this.debug = debug == null ? Map.of() : debug;
+        this.children = children == null ? List.of() : children;
         this.nodeTime = nodeTime;
     }
 
@@ -107,7 +107,7 @@ public ProfileResult(StreamInput in) throws IOException {
         if (in.getVersion().onOrAfter(LegacyESVersion.V_7_9_0)) {
             debug = in.readMap(StreamInput::readString, StreamInput::readGenericValue);
         } else {
-            debug = org.opensearch.common.collect.Map.of();
+            debug = Map.of();
         }
         children = in.readList(ProfileResult::new);
     }
diff --git a/server/src/main/resources/org/opensearch/bootstrap/test-framework.policy b/server/src/main/resources/org/opensearch/bootstrap/test-framework.policy
index bcf0b704374c9..60d0e9d15215a 100644
--- a/server/src/main/resources/org/opensearch/bootstrap/test-framework.policy
+++ b/server/src/main/resources/org/opensearch/bootstrap/test-framework.policy
@@ -123,6 +123,11 @@ grant codeBase "${codebase.junit-rt.jar}" {
   permission java.lang.reflect.ReflectPermission "suppressAccessChecks";
 };
 
+grant codeBase "${codebase.idea_rt.jar}" {
+  // allows IntelliJ IDEA (2022.3.3) JUnit test runner to control number of test iterations
+  permission java.lang.reflect.ReflectPermission "suppressAccessChecks";
+};
+
 grant codeBase "file:${gradle.dist.lib}/-" {
   // gradle test worker code needs a slew of permissions, we give full access here since gradle isn't a production
   // dependency and there's no point in exercising the security policy against it
diff --git a/server/src/test/java/org/opensearch/action/ActionListenerTests.java b/server/src/test/java/org/opensearch/action/ActionListenerTests.java
index bf64b4ed8a1a5..e56deb6088722 100644
--- a/server/src/test/java/org/opensearch/action/ActionListenerTests.java
+++ b/server/src/test/java/org/opensearch/action/ActionListenerTests.java
@@ -266,10 +266,9 @@ public void onFailure(Exception e) {
         assertThat(assertionError.getCause(), instanceOf(IllegalArgumentException.class));
         assertNull(exReference.get());
 
-        assertionError = expectThrows(
-            AssertionError.class,
-            () -> ActionListener.completeWith(listener, () -> { throw new IllegalArgumentException(); })
-        );
+        assertionError = expectThrows(AssertionError.class, () -> ActionListener.completeWith(listener, () -> {
+            throw new IllegalArgumentException();
+        }));
         assertThat(assertionError.getCause(), instanceOf(IllegalArgumentException.class));
         assertThat(exReference.get(), instanceOf(IllegalArgumentException.class));
     }
diff --git a/server/src/test/java/org/opensearch/action/admin/cluster/configuration/TransportAddVotingConfigExclusionsActionTests.java b/server/src/test/java/org/opensearch/action/admin/cluster/configuration/TransportAddVotingConfigExclusionsActionTests.java
index 03c6b5ab822c1..40a041e9b94e3 100644
--- a/server/src/test/java/org/opensearch/action/admin/cluster/configuration/TransportAddVotingConfigExclusionsActionTests.java
+++ b/server/src/test/java/org/opensearch/action/admin/cluster/configuration/TransportAddVotingConfigExclusionsActionTests.java
@@ -386,7 +386,9 @@ public void testExcludeAbsentNodesByNodeIds() throws InterruptedException {
                 Strings.EMPTY_ARRAY,
                 TimeValue.timeValueSeconds(30)
             ),
-            expectSuccess(e -> { countDownLatch.countDown(); })
+            expectSuccess(e -> {
+                countDownLatch.countDown();
+            })
         );
 
         assertTrue(countDownLatch.await(30, TimeUnit.SECONDS));
@@ -430,7 +432,9 @@ public void testExcludeAbsentNodesByNodeNames() throws InterruptedException {
             localNode,
             AddVotingConfigExclusionsAction.NAME,
             new AddVotingConfigExclusionsRequest("absent_node"),
-            expectSuccess(e -> { countDownLatch.countDown(); })
+            expectSuccess(e -> {
+                countDownLatch.countDown();
+            })
         );
 
         assertTrue(countDownLatch.await(30, TimeUnit.SECONDS));
diff --git a/server/src/test/java/org/opensearch/action/admin/indices/TransportAnalyzeActionTests.java b/server/src/test/java/org/opensearch/action/admin/indices/TransportAnalyzeActionTests.java
index 17cc539a5d561..f575be74a3e9b 100644
--- a/server/src/test/java/org/opensearch/action/admin/indices/TransportAnalyzeActionTests.java
+++ b/server/src/test/java/org/opensearch/action/admin/indices/TransportAnalyzeActionTests.java
@@ -380,10 +380,9 @@ public void testGetIndexAnalyserWithoutIndexAnalyzers() {
 
     public void testGetFieldAnalyzerWithoutIndexAnalyzers() {
         AnalyzeAction.Request req = new AnalyzeAction.Request().field("field").text("text");
-        IllegalArgumentException e = expectThrows(
-            IllegalArgumentException.class,
-            () -> { TransportAnalyzeAction.analyze(req, registry, null, maxTokenCount); }
-        );
+        IllegalArgumentException e = expectThrows(IllegalArgumentException.class, () -> {
+            TransportAnalyzeAction.analyze(req, registry, null, maxTokenCount);
+        });
         assertEquals(e.getMessage(), "analysis based on a specific field requires an index");
     }
 
diff --git a/server/src/test/java/org/opensearch/action/admin/indices/create/CreateIndexRequestBuilderTests.java b/server/src/test/java/org/opensearch/action/admin/indices/create/CreateIndexRequestBuilderTests.java
index 5bb9155a5a84c..89ae48d4cd854 100644
--- a/server/src/test/java/org/opensearch/action/admin/indices/create/CreateIndexRequestBuilderTests.java
+++ b/server/src/test/java/org/opensearch/action/admin/indices/create/CreateIndexRequestBuilderTests.java
@@ -74,10 +74,9 @@ public void tearDown() throws Exception {
     public void testSetSource() throws IOException {
         CreateIndexRequestBuilder builder = new CreateIndexRequestBuilder(this.testClient, CreateIndexAction.INSTANCE);
 
-        OpenSearchParseException e = expectThrows(
-            OpenSearchParseException.class,
-            () -> { builder.setSource("{\"" + KEY + "\" : \"" + VALUE + "\"}", XContentType.JSON); }
-        );
+        OpenSearchParseException e = expectThrows(OpenSearchParseException.class, () -> {
+            builder.setSource("{\"" + KEY + "\" : \"" + VALUE + "\"}", XContentType.JSON);
+        });
         assertEquals(String.format(Locale.ROOT, "unknown key [%s] for create index", KEY), e.getMessage());
 
         builder.setSource("{\"settings\" : {\"" + KEY + "\" : \"" + VALUE + "\"}}", XContentType.JSON);
diff --git a/server/src/test/java/org/opensearch/action/admin/indices/datastream/DeleteDataStreamRequestTests.java b/server/src/test/java/org/opensearch/action/admin/indices/datastream/DeleteDataStreamRequestTests.java
index b6e143d28b4aa..e33b873a52f19 100644
--- a/server/src/test/java/org/opensearch/action/admin/indices/datastream/DeleteDataStreamRequestTests.java
+++ b/server/src/test/java/org/opensearch/action/admin/indices/datastream/DeleteDataStreamRequestTests.java
@@ -95,11 +95,8 @@ public void testValidateRequestWithoutName() {
 
     public void testDeleteDataStream() {
         final String dataStreamName = "my-data-stream";
-        final List<String> otherIndices = randomSubsetOf(org.opensearch.common.collect.List.of("foo", "bar", "baz"));
-        ClusterState cs = getClusterStateWithDataStreams(
-            org.opensearch.common.collect.List.of(new Tuple<>(dataStreamName, 2)),
-            otherIndices
-        );
+        final List<String> otherIndices = randomSubsetOf(List.of("foo", "bar", "baz"));
+        ClusterState cs = getClusterStateWithDataStreams(List.of(new Tuple<>(dataStreamName, 2)), otherIndices);
         DeleteDataStreamAction.Request req = new DeleteDataStreamAction.Request(new String[] { dataStreamName });
         ClusterState newState = DeleteDataStreamAction.TransportAction.removeDataStream(getMetadataDeleteIndexService(), cs, req);
         assertThat(newState.metadata().dataStreams().size(), equalTo(0));
@@ -112,13 +109,13 @@ public void testDeleteDataStream() {
     public void testDeleteMultipleDataStreams() {
         String[] dataStreamNames = { "foo", "bar", "baz", "eggplant" };
         ClusterState cs = getClusterStateWithDataStreams(
-            org.opensearch.common.collect.List.of(
+            List.of(
                 new Tuple<>(dataStreamNames[0], randomIntBetween(1, 3)),
                 new Tuple<>(dataStreamNames[1], randomIntBetween(1, 3)),
                 new Tuple<>(dataStreamNames[2], randomIntBetween(1, 3)),
                 new Tuple<>(dataStreamNames[3], randomIntBetween(1, 3))
             ),
-            org.opensearch.common.collect.List.of()
+            List.of()
         );
 
         DeleteDataStreamAction.Request req = new DeleteDataStreamAction.Request(new String[] { "ba*", "eggplant" });
@@ -182,13 +179,13 @@ public void testDeleteNonexistentDataStream() {
         final String dataStreamName = "my-data-stream";
         String[] dataStreamNames = { "foo", "bar", "baz", "eggplant" };
         ClusterState cs = getClusterStateWithDataStreams(
-            org.opensearch.common.collect.List.of(
+            List.of(
                 new Tuple<>(dataStreamNames[0], randomIntBetween(1, 3)),
                 new Tuple<>(dataStreamNames[1], randomIntBetween(1, 3)),
                 new Tuple<>(dataStreamNames[2], randomIntBetween(1, 3)),
                 new Tuple<>(dataStreamNames[3], randomIntBetween(1, 3))
             ),
-            org.opensearch.common.collect.List.of()
+            List.of()
         );
         DeleteDataStreamAction.Request req = new DeleteDataStreamAction.Request(new String[] { dataStreamName });
         ClusterState newState = DeleteDataStreamAction.TransportAction.removeDataStream(getMetadataDeleteIndexService(), cs, req);
diff --git a/server/src/test/java/org/opensearch/action/admin/indices/datastream/GetDataStreamsRequestTests.java b/server/src/test/java/org/opensearch/action/admin/indices/datastream/GetDataStreamsRequestTests.java
index 25734a9824c41..54e83bc764cad 100644
--- a/server/src/test/java/org/opensearch/action/admin/indices/datastream/GetDataStreamsRequestTests.java
+++ b/server/src/test/java/org/opensearch/action/admin/indices/datastream/GetDataStreamsRequestTests.java
@@ -82,10 +82,7 @@ protected Request createTestInstance() {
 
     public void testGetDataStream() {
         final String dataStreamName = "my-data-stream";
-        ClusterState cs = getClusterStateWithDataStreams(
-            org.opensearch.common.collect.List.of(new Tuple<>(dataStreamName, 1)),
-            org.opensearch.common.collect.List.of()
-        );
+        ClusterState cs = getClusterStateWithDataStreams(List.of(new Tuple<>(dataStreamName, 1)), List.of());
         GetDataStreamAction.Request req = new GetDataStreamAction.Request(new String[] { dataStreamName });
         List<DataStream> dataStreams = GetDataStreamAction.TransportAction.getDataStreams(
             cs,
@@ -99,8 +96,8 @@ public void testGetDataStream() {
     public void testGetDataStreamsWithWildcards() {
         final String[] dataStreamNames = { "my-data-stream", "another-data-stream" };
         ClusterState cs = getClusterStateWithDataStreams(
-            org.opensearch.common.collect.List.of(new Tuple<>(dataStreamNames[0], 1), new Tuple<>(dataStreamNames[1], 1)),
-            org.opensearch.common.collect.List.of()
+            List.of(new Tuple<>(dataStreamNames[0], 1), new Tuple<>(dataStreamNames[1], 1)),
+            List.of()
         );
 
         GetDataStreamAction.Request req = new GetDataStreamAction.Request(new String[] { dataStreamNames[1].substring(0, 5) + "*" });
@@ -144,8 +141,8 @@ public void testGetDataStreamsWithWildcards() {
     public void testGetDataStreamsWithoutWildcards() {
         final String[] dataStreamNames = { "my-data-stream", "another-data-stream" };
         ClusterState cs = getClusterStateWithDataStreams(
-            org.opensearch.common.collect.List.of(new Tuple<>(dataStreamNames[0], 1), new Tuple<>(dataStreamNames[1], 1)),
-            org.opensearch.common.collect.List.of()
+            List.of(new Tuple<>(dataStreamNames[0], 1), new Tuple<>(dataStreamNames[1], 1)),
+            List.of()
         );
 
         GetDataStreamAction.Request req = new GetDataStreamAction.Request(new String[] { dataStreamNames[0], dataStreamNames[1] });
diff --git a/server/src/test/java/org/opensearch/action/admin/indices/get/GetIndexActionTests.java b/server/src/test/java/org/opensearch/action/admin/indices/get/GetIndexActionTests.java
index 001efb32c2988..81e73c4889d3b 100644
--- a/server/src/test/java/org/opensearch/action/admin/indices/get/GetIndexActionTests.java
+++ b/server/src/test/java/org/opensearch/action/admin/indices/get/GetIndexActionTests.java
@@ -109,7 +109,9 @@ public void testIncludeDefaults() {
                     "index.refresh_interval should be set as we are including defaults",
                     defaultsResponse.getSetting(indexName, "index.refresh_interval")
                 ),
-                exception -> { throw new AssertionError(exception); }
+                exception -> {
+                    throw new AssertionError(exception);
+                }
             )
         );
     }
@@ -124,7 +126,9 @@ public void testDoNotIncludeDefaults() {
                     "index.refresh_interval should be null as it was never set",
                     noDefaultsResponse.getSetting(indexName, "index.refresh_interval")
                 ),
-                exception -> { throw new AssertionError(exception); }
+                exception -> {
+                    throw new AssertionError(exception);
+                }
             )
         );
     }
diff --git a/server/src/test/java/org/opensearch/action/admin/indices/mapping/put/PutMappingRequestTests.java b/server/src/test/java/org/opensearch/action/admin/indices/mapping/put/PutMappingRequestTests.java
index e6eba34987a44..3fc57f4e32435 100644
--- a/server/src/test/java/org/opensearch/action/admin/indices/mapping/put/PutMappingRequestTests.java
+++ b/server/src/test/java/org/opensearch/action/admin/indices/mapping/put/PutMappingRequestTests.java
@@ -164,21 +164,18 @@ private static PutMappingRequest createTestItem() throws IOException {
 
     public void testResolveIndicesWithWriteIndexOnlyAndDataStreamsAndWriteAliases() {
         String[] dataStreamNames = { "foo", "bar", "baz" };
-        List<Tuple<String, Integer>> dsMetadata = org.opensearch.common.collect.List.of(
+        List<Tuple<String, Integer>> dsMetadata = List.of(
             tuple(dataStreamNames[0], randomIntBetween(1, 3)),
             tuple(dataStreamNames[1], randomIntBetween(1, 3)),
             tuple(dataStreamNames[2], randomIntBetween(1, 3))
         );
 
-        ClusterState cs = DeleteDataStreamRequestTests.getClusterStateWithDataStreams(
-            dsMetadata,
-            org.opensearch.common.collect.List.of("index1", "index2", "index3")
-        );
+        ClusterState cs = DeleteDataStreamRequestTests.getClusterStateWithDataStreams(dsMetadata, List.of("index1", "index2", "index3"));
         cs = addAliases(
             cs,
-            org.opensearch.common.collect.List.of(
-                tuple("alias1", org.opensearch.common.collect.List.of(tuple("index1", false), tuple("index2", true))),
-                tuple("alias2", org.opensearch.common.collect.List.of(tuple("index2", false), tuple("index3", true)))
+            List.of(
+                tuple("alias1", List.of(tuple("index1", false), tuple("index2", true))),
+                tuple("alias2", List.of(tuple("index2", false), tuple("index3", true)))
             )
         );
         PutMappingRequest request = new PutMappingRequest().indices("foo", "alias1", "alias2").writeIndexOnly(true);
@@ -195,21 +192,18 @@ public void testResolveIndicesWithWriteIndexOnlyAndDataStreamsAndWriteAliases()
 
     public void testResolveIndicesWithoutWriteIndexOnlyAndDataStreamsAndWriteAliases() {
         String[] dataStreamNames = { "foo", "bar", "baz" };
-        List<Tuple<String, Integer>> dsMetadata = org.opensearch.common.collect.List.of(
+        List<Tuple<String, Integer>> dsMetadata = List.of(
             tuple(dataStreamNames[0], randomIntBetween(1, 3)),
             tuple(dataStreamNames[1], randomIntBetween(1, 3)),
             tuple(dataStreamNames[2], randomIntBetween(1, 3))
         );
 
-        ClusterState cs = DeleteDataStreamRequestTests.getClusterStateWithDataStreams(
-            dsMetadata,
-            org.opensearch.common.collect.List.of("index1", "index2", "index3")
-        );
+        ClusterState cs = DeleteDataStreamRequestTests.getClusterStateWithDataStreams(dsMetadata, List.of("index1", "index2", "index3"));
         cs = addAliases(
             cs,
-            org.opensearch.common.collect.List.of(
-                tuple("alias1", org.opensearch.common.collect.List.of(tuple("index1", false), tuple("index2", true))),
-                tuple("alias2", org.opensearch.common.collect.List.of(tuple("index2", false), tuple("index3", true)))
+            List.of(
+                tuple("alias1", List.of(tuple("index1", false), tuple("index2", true))),
+                tuple("alias2", List.of(tuple("index2", false), tuple("index3", true)))
             )
         );
         PutMappingRequest request = new PutMappingRequest().indices("foo", "alias1", "alias2");
@@ -221,28 +215,25 @@ public void testResolveIndicesWithoutWriteIndexOnlyAndDataStreamsAndWriteAliases
         List<String> indexNames = Arrays.stream(indices).map(Index::getName).collect(Collectors.toList());
         IndexAbstraction expectedDs = cs.metadata().getIndicesLookup().get("foo");
         List<String> expectedIndices = expectedDs.getIndices().stream().map(im -> im.getIndex().getName()).collect(Collectors.toList());
-        expectedIndices.addAll(org.opensearch.common.collect.List.of("index1", "index2", "index3"));
+        expectedIndices.addAll(List.of("index1", "index2", "index3"));
         // should resolve the data stream and each alias to _all_ their respective indices
         assertThat(indexNames, containsInAnyOrder(expectedIndices.toArray()));
     }
 
     public void testResolveIndicesWithWriteIndexOnlyAndDataStreamAndIndex() {
         String[] dataStreamNames = { "foo", "bar", "baz" };
-        List<Tuple<String, Integer>> dsMetadata = org.opensearch.common.collect.List.of(
+        List<Tuple<String, Integer>> dsMetadata = List.of(
             tuple(dataStreamNames[0], randomIntBetween(1, 3)),
             tuple(dataStreamNames[1], randomIntBetween(1, 3)),
             tuple(dataStreamNames[2], randomIntBetween(1, 3))
         );
 
-        ClusterState cs = DeleteDataStreamRequestTests.getClusterStateWithDataStreams(
-            dsMetadata,
-            org.opensearch.common.collect.List.of("index1", "index2", "index3")
-        );
+        ClusterState cs = DeleteDataStreamRequestTests.getClusterStateWithDataStreams(dsMetadata, List.of("index1", "index2", "index3"));
         cs = addAliases(
             cs,
-            org.opensearch.common.collect.List.of(
-                tuple("alias1", org.opensearch.common.collect.List.of(tuple("index1", false), tuple("index2", true))),
-                tuple("alias2", org.opensearch.common.collect.List.of(tuple("index2", false), tuple("index3", true)))
+            List.of(
+                tuple("alias1", List.of(tuple("index1", false), tuple("index2", true))),
+                tuple("alias2", List.of(tuple("index2", false), tuple("index3", true)))
             )
         );
         PutMappingRequest request = new PutMappingRequest().indices("foo", "index3").writeIndexOnly(true);
@@ -254,28 +245,25 @@ public void testResolveIndicesWithWriteIndexOnlyAndDataStreamAndIndex() {
         List<String> indexNames = Arrays.stream(indices).map(Index::getName).collect(Collectors.toList());
         IndexAbstraction expectedDs = cs.metadata().getIndicesLookup().get("foo");
         List<String> expectedIndices = expectedDs.getIndices().stream().map(im -> im.getIndex().getName()).collect(Collectors.toList());
-        expectedIndices.addAll(org.opensearch.common.collect.List.of("index1", "index2", "index3"));
+        expectedIndices.addAll(List.of("index1", "index2", "index3"));
         // should resolve the data stream and each alias to _all_ their respective indices
         assertThat(indexNames, containsInAnyOrder(expectedDs.getWriteIndex().getIndex().getName(), "index3"));
     }
 
     public void testResolveIndicesWithWriteIndexOnlyAndNoSingleWriteIndex() {
         String[] dataStreamNames = { "foo", "bar", "baz" };
-        List<Tuple<String, Integer>> dsMetadata = org.opensearch.common.collect.List.of(
+        List<Tuple<String, Integer>> dsMetadata = List.of(
             tuple(dataStreamNames[0], randomIntBetween(1, 3)),
             tuple(dataStreamNames[1], randomIntBetween(1, 3)),
             tuple(dataStreamNames[2], randomIntBetween(1, 3))
         );
 
-        ClusterState cs = DeleteDataStreamRequestTests.getClusterStateWithDataStreams(
-            dsMetadata,
-            org.opensearch.common.collect.List.of("index1", "index2", "index3")
-        );
+        ClusterState cs = DeleteDataStreamRequestTests.getClusterStateWithDataStreams(dsMetadata, List.of("index1", "index2", "index3"));
         final ClusterState cs2 = addAliases(
             cs,
-            org.opensearch.common.collect.List.of(
-                tuple("alias1", org.opensearch.common.collect.List.of(tuple("index1", false), tuple("index2", true))),
-                tuple("alias2", org.opensearch.common.collect.List.of(tuple("index2", false), tuple("index3", true)))
+            List.of(
+                tuple("alias1", List.of(tuple("index1", false), tuple("index2", true))),
+                tuple("alias2", List.of(tuple("index2", false), tuple("index3", true)))
             )
         );
         PutMappingRequest request = new PutMappingRequest().indices("*").writeIndexOnly(true);
@@ -288,21 +276,18 @@ public void testResolveIndicesWithWriteIndexOnlyAndNoSingleWriteIndex() {
 
     public void testResolveIndicesWithWriteIndexOnlyAndAliasWithoutWriteIndex() {
         String[] dataStreamNames = { "foo", "bar", "baz" };
-        List<Tuple<String, Integer>> dsMetadata = org.opensearch.common.collect.List.of(
+        List<Tuple<String, Integer>> dsMetadata = List.of(
             tuple(dataStreamNames[0], randomIntBetween(1, 3)),
             tuple(dataStreamNames[1], randomIntBetween(1, 3)),
             tuple(dataStreamNames[2], randomIntBetween(1, 3))
         );
 
-        ClusterState cs = DeleteDataStreamRequestTests.getClusterStateWithDataStreams(
-            dsMetadata,
-            org.opensearch.common.collect.List.of("index1", "index2", "index3")
-        );
+        ClusterState cs = DeleteDataStreamRequestTests.getClusterStateWithDataStreams(dsMetadata, List.of("index1", "index2", "index3"));
         final ClusterState cs2 = addAliases(
             cs,
-            org.opensearch.common.collect.List.of(
-                tuple("alias1", org.opensearch.common.collect.List.of(tuple("index1", false), tuple("index2", false))),
-                tuple("alias2", org.opensearch.common.collect.List.of(tuple("index2", false), tuple("index3", false)))
+            List.of(
+                tuple("alias1", List.of(tuple("index1", false), tuple("index2", false))),
+                tuple("alias2", List.of(tuple("index2", false), tuple("index3", false)))
             )
         );
         PutMappingRequest request = new PutMappingRequest().indices("alias2").writeIndexOnly(true);
diff --git a/server/src/test/java/org/opensearch/action/admin/indices/resolve/ResolveIndexResponseTests.java b/server/src/test/java/org/opensearch/action/admin/indices/resolve/ResolveIndexResponseTests.java
index 9588e1272577d..ba1150aef6703 100644
--- a/server/src/test/java/org/opensearch/action/admin/indices/resolve/ResolveIndexResponseTests.java
+++ b/server/src/test/java/org/opensearch/action/admin/indices/resolve/ResolveIndexResponseTests.java
@@ -92,9 +92,7 @@ protected Response createTestInstance() {
     private static ResolvedIndex createTestResolvedIndexInstance() {
         String name = randomAlphaOfLength(6);
         String[] aliases = randomStringArray(0, 5);
-        String[] attributes = randomSubsetOf(org.opensearch.common.collect.List.of("open", "hidden", "frozen")).toArray(
-            Strings.EMPTY_ARRAY
-        );
+        String[] attributes = randomSubsetOf(List.of("open", "hidden", "frozen")).toArray(Strings.EMPTY_ARRAY);
         String dataStream = randomBoolean() ? randomAlphaOfLength(6) : null;
 
         return new ResolvedIndex(name, aliases, attributes, dataStream);
diff --git a/server/src/test/java/org/opensearch/action/admin/indices/template/put/PutComposableIndexTemplateRequestTests.java b/server/src/test/java/org/opensearch/action/admin/indices/template/put/PutComposableIndexTemplateRequestTests.java
index 98e833b051032..d73ba0c7e9105 100644
--- a/server/src/test/java/org/opensearch/action/admin/indices/template/put/PutComposableIndexTemplateRequestTests.java
+++ b/server/src/test/java/org/opensearch/action/admin/indices/template/put/PutComposableIndexTemplateRequestTests.java
@@ -71,15 +71,7 @@ protected PutComposableIndexTemplateAction.Request mutateInstance(PutComposableI
 
     public void testPutGlobalTemplatesCannotHaveHiddenIndexSetting() {
         Template template = new Template(Settings.builder().put(IndexMetadata.SETTING_INDEX_HIDDEN, true).build(), null, null);
-        ComposableIndexTemplate globalTemplate = new ComposableIndexTemplate(
-            org.opensearch.common.collect.List.of("*"),
-            template,
-            null,
-            null,
-            null,
-            null,
-            null
-        );
+        ComposableIndexTemplate globalTemplate = new ComposableIndexTemplate(List.of("*"), template, null, null, null, null, null);
 
         PutComposableIndexTemplateAction.Request request = new PutComposableIndexTemplateAction.Request("test");
         request.indexTemplate(globalTemplate);
diff --git a/server/src/test/java/org/opensearch/action/bulk/BulkRequestParserTests.java b/server/src/test/java/org/opensearch/action/bulk/BulkRequestParserTests.java
index 32a0b3723f7ae..c51c9f7ea77dc 100644
--- a/server/src/test/java/org/opensearch/action/bulk/BulkRequestParserTests.java
+++ b/server/src/test/java/org/opensearch/action/bulk/BulkRequestParserTests.java
@@ -58,49 +58,19 @@ public void testIndexRequest() throws IOException {
         }, req -> fail(), req -> fail());
         assertTrue(parsed.get());
 
-        parser.parse(
-            request,
-            "foo",
-            null,
-            null,
-            null,
-            true,
-            false,
-            XContentType.JSON,
-            indexRequest -> { assertTrue(indexRequest.isRequireAlias()); },
-            req -> fail(),
-            req -> fail()
-        );
+        parser.parse(request, "foo", null, null, null, true, false, XContentType.JSON, indexRequest -> {
+            assertTrue(indexRequest.isRequireAlias());
+        }, req -> fail(), req -> fail());
 
         request = new BytesArray("{ \"index\":{ \"_id\": \"bar\", \"require_alias\": true } }\n{}\n");
-        parser.parse(
-            request,
-            "foo",
-            null,
-            null,
-            null,
-            null,
-            false,
-            XContentType.JSON,
-            indexRequest -> { assertTrue(indexRequest.isRequireAlias()); },
-            req -> fail(),
-            req -> fail()
-        );
+        parser.parse(request, "foo", null, null, null, null, false, XContentType.JSON, indexRequest -> {
+            assertTrue(indexRequest.isRequireAlias());
+        }, req -> fail(), req -> fail());
 
         request = new BytesArray("{ \"index\":{ \"_id\": \"bar\", \"require_alias\": false } }\n{}\n");
-        parser.parse(
-            request,
-            "foo",
-            null,
-            null,
-            null,
-            true,
-            false,
-            XContentType.JSON,
-            indexRequest -> { assertFalse(indexRequest.isRequireAlias()); },
-            req -> fail(),
-            req -> fail()
-        );
+        parser.parse(request, "foo", null, null, null, true, false, XContentType.JSON, indexRequest -> {
+            assertFalse(indexRequest.isRequireAlias());
+        }, req -> fail(), req -> fail());
     }
 
     public void testDeleteRequest() throws IOException {
@@ -129,49 +99,19 @@ public void testUpdateRequest() throws IOException {
         }, req -> fail());
         assertTrue(parsed.get());
 
-        parser.parse(
-            request,
-            "foo",
-            null,
-            null,
-            null,
-            true,
-            false,
-            XContentType.JSON,
-            req -> fail(),
-            updateRequest -> { assertTrue(updateRequest.isRequireAlias()); },
-            req -> fail()
-        );
+        parser.parse(request, "foo", null, null, null, true, false, XContentType.JSON, req -> fail(), updateRequest -> {
+            assertTrue(updateRequest.isRequireAlias());
+        }, req -> fail());
 
         request = new BytesArray("{ \"update\":{ \"_id\": \"bar\", \"require_alias\": true } }\n{}\n");
-        parser.parse(
-            request,
-            "foo",
-            null,
-            null,
-            null,
-            null,
-            false,
-            XContentType.JSON,
-            req -> fail(),
-            updateRequest -> { assertTrue(updateRequest.isRequireAlias()); },
-            req -> fail()
-        );
+        parser.parse(request, "foo", null, null, null, null, false, XContentType.JSON, req -> fail(), updateRequest -> {
+            assertTrue(updateRequest.isRequireAlias());
+        }, req -> fail());
 
         request = new BytesArray("{ \"update\":{ \"_id\": \"bar\", \"require_alias\": false } }\n{}\n");
-        parser.parse(
-            request,
-            "foo",
-            null,
-            null,
-            null,
-            true,
-            false,
-            XContentType.JSON,
-            req -> fail(),
-            updateRequest -> { assertFalse(updateRequest.isRequireAlias()); },
-            req -> fail()
-        );
+        parser.parse(request, "foo", null, null, null, true, false, XContentType.JSON, req -> fail(), updateRequest -> {
+            assertFalse(updateRequest.isRequireAlias());
+        }, req -> fail());
     }
 
     public void testBarfOnLackOfTrailingNewline() {
diff --git a/server/src/test/java/org/opensearch/action/bulk/TransportBulkActionIndicesThatCannotBeCreatedTests.java b/server/src/test/java/org/opensearch/action/bulk/TransportBulkActionIndicesThatCannotBeCreatedTests.java
index 32e9dd44008cd..0846a5f8dec5c 100644
--- a/server/src/test/java/org/opensearch/action/bulk/TransportBulkActionIndicesThatCannotBeCreatedTests.java
+++ b/server/src/test/java/org/opensearch/action/bulk/TransportBulkActionIndicesThatCannotBeCreatedTests.java
@@ -96,11 +96,9 @@ public void testAllFail() {
         bulkRequest.add(new IndexRequest("can't"));
         bulkRequest.add(new DeleteRequest("do").version(0).versionType(VersionType.EXTERNAL));
         bulkRequest.add(new UpdateRequest("nothin", randomAlphaOfLength(5)));
-        indicesThatCannotBeCreatedTestCase(
-            new HashSet<>(Arrays.asList("no", "can't", "do", "nothin")),
-            bulkRequest,
-            index -> { throw new IndexNotFoundException("Can't make it because I say so"); }
-        );
+        indicesThatCannotBeCreatedTestCase(new HashSet<>(Arrays.asList("no", "can't", "do", "nothin")), bulkRequest, index -> {
+            throw new IndexNotFoundException("Can't make it because I say so");
+        });
     }
 
     public void testSomeFail() {
diff --git a/server/src/test/java/org/opensearch/action/bulk/TransportBulkActionIngestTests.java b/server/src/test/java/org/opensearch/action/bulk/TransportBulkActionIngestTests.java
index 202f1b7dcb5b4..5b96c2a71dbf8 100644
--- a/server/src/test/java/org/opensearch/action/bulk/TransportBulkActionIngestTests.java
+++ b/server/src/test/java/org/opensearch/action/bulk/TransportBulkActionIngestTests.java
@@ -302,11 +302,9 @@ public void testIngestSkipped() throws Exception {
     public void testSingleItemBulkActionIngestSkipped() throws Exception {
         IndexRequest indexRequest = new IndexRequest("index").id("id");
         indexRequest.source(emptyMap());
-        singleItemBulkWriteAction.execute(
-            null,
-            indexRequest,
-            ActionListener.wrap(response -> {}, exception -> { throw new AssertionError(exception); })
-        );
+        singleItemBulkWriteAction.execute(null, indexRequest, ActionListener.wrap(response -> {}, exception -> {
+            throw new AssertionError(exception);
+        }));
         assertTrue(action.isExecuted);
         verifyNoInteractions(ingestService);
     }
diff --git a/server/src/test/java/org/opensearch/action/bulk/TransportBulkActionTests.java b/server/src/test/java/org/opensearch/action/bulk/TransportBulkActionTests.java
index 5eb395cb05971..6c23092c789d1 100644
--- a/server/src/test/java/org/opensearch/action/bulk/TransportBulkActionTests.java
+++ b/server/src/test/java/org/opensearch/action/bulk/TransportBulkActionTests.java
@@ -74,6 +74,7 @@
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
+import java.util.Map;
 import java.util.SortedMap;
 import java.util.TreeMap;
 import java.util.concurrent.TimeUnit;
@@ -343,19 +344,17 @@ public void testIncludesSystem() {
             ".bar",
             new Index(IndexMetadata.builder(".bar").settings(settings).system(true).numberOfShards(1).numberOfReplicas(0).build())
         );
-        SystemIndices systemIndices = new SystemIndices(
-            org.opensearch.common.collect.Map.of("plugin", org.opensearch.common.collect.List.of(new SystemIndexDescriptor(".test", "")))
-        );
-        List<String> onlySystem = org.opensearch.common.collect.List.of(".foo", ".bar");
+        SystemIndices systemIndices = new SystemIndices(Map.of("plugin", List.of(new SystemIndexDescriptor(".test", ""))));
+        List<String> onlySystem = List.of(".foo", ".bar");
         assertTrue(bulkAction.includesSystem(buildBulkRequest(onlySystem), indicesLookup, systemIndices));
 
-        onlySystem = org.opensearch.common.collect.List.of(".foo", ".bar", ".test");
+        onlySystem = List.of(".foo", ".bar", ".test");
         assertTrue(bulkAction.includesSystem(buildBulkRequest(onlySystem), indicesLookup, systemIndices));
 
-        List<String> nonSystem = org.opensearch.common.collect.List.of("foo", "bar");
+        List<String> nonSystem = List.of("foo", "bar");
         assertFalse(bulkAction.includesSystem(buildBulkRequest(nonSystem), indicesLookup, systemIndices));
 
-        List<String> mixed = org.opensearch.common.collect.List.of(".foo", ".test", "other");
+        List<String> mixed = List.of(".foo", ".test", "other");
         assertTrue(bulkAction.includesSystem(buildBulkRequest(mixed), indicesLookup, systemIndices));
     }
 
diff --git a/server/src/test/java/org/opensearch/action/bulk/TransportShardBulkActionTests.java b/server/src/test/java/org/opensearch/action/bulk/TransportShardBulkActionTests.java
index 2aff8f6bfc6ab..1d7828027baa0 100644
--- a/server/src/test/java/org/opensearch/action/bulk/TransportShardBulkActionTests.java
+++ b/server/src/test/java/org/opensearch/action/bulk/TransportShardBulkActionTests.java
@@ -69,6 +69,7 @@
 import org.opensearch.index.IndexService;
 import org.opensearch.index.IndexSettings;
 import org.opensearch.index.IndexingPressureService;
+import org.opensearch.index.SegmentReplicationPressureService;
 import org.opensearch.index.VersionType;
 import org.opensearch.index.engine.Engine;
 import org.opensearch.index.engine.VersionConflictEngineException;
@@ -1070,6 +1071,7 @@ public void testHandlePrimaryTermValidationRequestWithDifferentAllocationId() {
             mock(UpdateHelper.class),
             mock(ActionFilters.class),
             mock(IndexingPressureService.class),
+            mock(SegmentReplicationPressureService.class),
             mock(SystemIndices.class)
         );
         action.handlePrimaryTermValidationRequest(
@@ -1099,6 +1101,7 @@ public void testHandlePrimaryTermValidationRequestWithOlderPrimaryTerm() {
             mock(UpdateHelper.class),
             mock(ActionFilters.class),
             mock(IndexingPressureService.class),
+            mock(SegmentReplicationPressureService.class),
             mock(SystemIndices.class)
         );
         action.handlePrimaryTermValidationRequest(
@@ -1128,6 +1131,7 @@ public void testHandlePrimaryTermValidationRequestSuccess() {
             mock(UpdateHelper.class),
             mock(ActionFilters.class),
             mock(IndexingPressureService.class),
+            mock(SegmentReplicationPressureService.class),
             mock(SystemIndices.class)
         );
         action.handlePrimaryTermValidationRequest(
@@ -1168,6 +1172,7 @@ private TransportShardBulkAction createAction() {
             mock(UpdateHelper.class),
             mock(ActionFilters.class),
             mock(IndexingPressureService.class),
+            mock(SegmentReplicationPressureService.class),
             mock(SystemIndices.class)
         );
     }
diff --git a/server/src/test/java/org/opensearch/action/search/SearchAsyncActionTests.java b/server/src/test/java/org/opensearch/action/search/SearchAsyncActionTests.java
index d6a0ecd0512dc..277f2f1dee0bf 100644
--- a/server/src/test/java/org/opensearch/action/search/SearchAsyncActionTests.java
+++ b/server/src/test/java/org/opensearch/action/search/SearchAsyncActionTests.java
@@ -317,7 +317,9 @@ public void testFanOutAndCollect() throws InterruptedException {
         AtomicReference<TestSearchResponse> response = new AtomicReference<>();
         ActionListener<SearchResponse> responseListener = ActionListener.wrap(
             searchResponse -> response.set((TestSearchResponse) searchResponse),
-            (e) -> { throw new AssertionError("unexpected", e); }
+            (e) -> {
+                throw new AssertionError("unexpected", e);
+            }
         );
         DiscoveryNode primaryNode = new DiscoveryNode("node_1", buildNewFakeTransportAddress(), Version.CURRENT);
         DiscoveryNode replicaNode = new DiscoveryNode("node_2", buildNewFakeTransportAddress(), Version.CURRENT);
diff --git a/server/src/test/java/org/opensearch/action/support/AutoCreateIndexTests.java b/server/src/test/java/org/opensearch/action/support/AutoCreateIndexTests.java
index 068414678e860..7263cbe90c1b7 100644
--- a/server/src/test/java/org/opensearch/action/support/AutoCreateIndexTests.java
+++ b/server/src/test/java/org/opensearch/action/support/AutoCreateIndexTests.java
@@ -231,7 +231,7 @@ public void testUpdate() {
             settings,
             clusterSettings,
             new IndexNameExpressionResolver(new ThreadContext(Settings.EMPTY)),
-            new SystemIndices(org.opensearch.common.collect.Map.of())
+            new SystemIndices(Map.of())
         );
         assertThat(autoCreateIndex.getAutoCreate().isAutoCreateIndex(), equalTo(value));
 
@@ -257,12 +257,7 @@ private static ClusterState buildClusterState(String... indices) {
     }
 
     private AutoCreateIndex newAutoCreateIndex(Settings settings) {
-        SystemIndices systemIndices = new SystemIndices(
-            org.opensearch.common.collect.Map.of(
-                "plugin",
-                org.opensearch.common.collect.List.of(new SystemIndexDescriptor(TEST_SYSTEM_INDEX_NAME, ""))
-            )
-        );
+        SystemIndices systemIndices = new SystemIndices(Map.of("plugin", List.of(new SystemIndexDescriptor(TEST_SYSTEM_INDEX_NAME, ""))));
         return new AutoCreateIndex(
             settings,
             new ClusterSettings(settings, ClusterSettings.BUILT_IN_CLUSTER_SETTINGS),
diff --git a/server/src/test/java/org/opensearch/client/OriginSettingClientTests.java b/server/src/test/java/org/opensearch/client/OriginSettingClientTests.java
index 2f24ff3fb1f29..eca49516f42c2 100644
--- a/server/src/test/java/org/opensearch/client/OriginSettingClientTests.java
+++ b/server/src/test/java/org/opensearch/client/OriginSettingClientTests.java
@@ -77,9 +77,8 @@ protected <Request extends ActionRequest, Response extends ActionResponse> void
     }
 
     private <T> ActionListener<T> listenerThatAssertsOriginNotSet(ThreadContext threadContext) {
-        return ActionListener.wrap(
-            r -> { assertNull(threadContext.getTransient(ThreadContext.ACTION_ORIGIN_TRANSIENT_NAME)); },
-            e -> { fail("didn't expect to fail but: " + e); }
-        );
+        return ActionListener.wrap(r -> { assertNull(threadContext.getTransient(ThreadContext.ACTION_ORIGIN_TRANSIENT_NAME)); }, e -> {
+            fail("didn't expect to fail but: " + e);
+        });
     }
 }
diff --git a/server/src/test/java/org/opensearch/cluster/InternalClusterInfoServiceSchedulingTests.java b/server/src/test/java/org/opensearch/cluster/InternalClusterInfoServiceSchedulingTests.java
index 70fdb91ee0632..1cd21482566ef 100644
--- a/server/src/test/java/org/opensearch/cluster/InternalClusterInfoServiceSchedulingTests.java
+++ b/server/src/test/java/org/opensearch/cluster/InternalClusterInfoServiceSchedulingTests.java
@@ -59,6 +59,7 @@
 import org.opensearch.test.client.NoOpClient;
 import org.opensearch.threadpool.ThreadPool;
 
+import java.util.Set;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 import static org.opensearch.cluster.InternalClusterInfoService.INTERNAL_CLUSTER_INFO_UPDATE_INTERVAL_SETTING;
@@ -93,7 +94,9 @@ protected PrioritizedOpenSearchThreadPoolExecutor createThreadPoolExecutor() {
             "test",
             "clusterManagerService",
             threadPool,
-            r -> { fail("cluster-manager service should not run any tasks"); }
+            r -> {
+                fail("cluster-manager service should not run any tasks");
+            }
         );
 
         final ClusterService clusterService = new ClusterService(settings, clusterSettings, clusterManagerService, clusterApplierService);
@@ -209,11 +212,7 @@ protected <Request extends ActionRequest, Response extends ActionResponse> void
             if (request instanceof NodesStatsRequest || request instanceof IndicesStatsRequest) {
                 requestCount++;
                 // ClusterInfoService handles ClusterBlockExceptions quietly, so we invent such an exception to avoid excess logging
-                listener.onFailure(
-                    new ClusterBlockException(
-                        org.opensearch.common.collect.Set.of(NoClusterManagerBlockService.NO_CLUSTER_MANAGER_BLOCK_ALL)
-                    )
-                );
+                listener.onFailure(new ClusterBlockException(Set.of(NoClusterManagerBlockService.NO_CLUSTER_MANAGER_BLOCK_ALL)));
             } else {
                 fail("unexpected action: " + action.name());
             }
diff --git a/server/src/test/java/org/opensearch/cluster/action/index/MappingUpdatedActionTests.java b/server/src/test/java/org/opensearch/cluster/action/index/MappingUpdatedActionTests.java
index 7325024138500..20fde9fc66c32 100644
--- a/server/src/test/java/org/opensearch/cluster/action/index/MappingUpdatedActionTests.java
+++ b/server/src/test/java/org/opensearch/cluster/action/index/MappingUpdatedActionTests.java
@@ -45,7 +45,6 @@
 import org.opensearch.cluster.node.DiscoveryNode;
 import org.opensearch.cluster.node.DiscoveryNodes;
 import org.opensearch.cluster.service.ClusterService;
-import org.opensearch.common.collect.Map;
 import org.opensearch.common.settings.ClusterSettings;
 import org.opensearch.common.settings.Settings;
 import org.opensearch.index.Index;
@@ -57,6 +56,7 @@
 import org.opensearch.test.OpenSearchTestCase;
 
 import java.util.List;
+import java.util.Map;
 import java.util.concurrent.CopyOnWriteArrayList;
 
 import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_VERSION_CREATED;
diff --git a/server/src/test/java/org/opensearch/cluster/action/shard/routing/weighted/get/TransportGetWeightedRoutingActionTests.java b/server/src/test/java/org/opensearch/cluster/action/shard/routing/weighted/get/TransportGetWeightedRoutingActionTests.java
index df5b6566b503e..a0ac9d94c8c37 100644
--- a/server/src/test/java/org/opensearch/cluster/action/shard/routing/weighted/get/TransportGetWeightedRoutingActionTests.java
+++ b/server/src/test/java/org/opensearch/cluster/action/shard/routing/weighted/get/TransportGetWeightedRoutingActionTests.java
@@ -41,6 +41,7 @@
 
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
@@ -129,7 +130,7 @@ private ClusterState addClusterManagerNodes(ClusterState clusterState) {
 
     private ClusterState addDataNodeForAZone(ClusterState clusterState, String zone, String... nodeIds) {
         DiscoveryNodes.Builder nodeBuilder = DiscoveryNodes.builder(clusterState.nodes());
-        org.opensearch.common.collect.List.of(nodeIds)
+        List.of(nodeIds)
             .forEach(
                 nodeId -> nodeBuilder.add(
                     new DiscoveryNode(
@@ -148,7 +149,7 @@ private ClusterState addDataNodeForAZone(ClusterState clusterState, String zone,
     private ClusterState addClusterManagerNodeForAZone(ClusterState clusterState, String zone, String... nodeIds) {
 
         DiscoveryNodes.Builder nodeBuilder = DiscoveryNodes.builder(clusterState.nodes());
-        org.opensearch.common.collect.List.of(nodeIds)
+        List.of(nodeIds)
             .forEach(
                 nodeId -> nodeBuilder.add(
                     new DiscoveryNode(
diff --git a/server/src/test/java/org/opensearch/cluster/coordination/ClusterBootstrapServiceDeprecatedMasterTests.java b/server/src/test/java/org/opensearch/cluster/coordination/ClusterBootstrapServiceDeprecatedMasterTests.java
index fb3a628827462..137de1355f11b 100644
--- a/server/src/test/java/org/opensearch/cluster/coordination/ClusterBootstrapServiceDeprecatedMasterTests.java
+++ b/server/src/test/java/org/opensearch/cluster/coordination/ClusterBootstrapServiceDeprecatedMasterTests.java
@@ -125,9 +125,9 @@ public void testBootstrapsAutomaticallyWithDefaultConfiguration() {
             settings.put(UNCONFIGURED_BOOTSTRAP_TIMEOUT_SETTING.getKey(), timeout + "ms");
         }
 
-        final AtomicReference<Supplier<Iterable<DiscoveryNode>>> discoveredNodesSupplier = new AtomicReference<>(
-            () -> { throw new AssertionError("should not be called yet"); }
-        );
+        final AtomicReference<Supplier<Iterable<DiscoveryNode>>> discoveredNodesSupplier = new AtomicReference<>(() -> {
+            throw new AssertionError("should not be called yet");
+        });
 
         final AtomicBoolean bootstrapped = new AtomicBoolean();
         ClusterBootstrapService clusterBootstrapService = new ClusterBootstrapService(
@@ -163,13 +163,9 @@ public void testDoesNothingByDefaultIfMasterNodesConfigured() {
     }
 
     private void testDoesNothingWithSettings(Settings.Builder builder) {
-        ClusterBootstrapService clusterBootstrapService = new ClusterBootstrapService(
-            builder.build(),
-            transportService,
-            () -> { throw new AssertionError("should not be called"); },
-            () -> false,
-            vc -> { throw new AssertionError("should not be called"); }
-        );
+        ClusterBootstrapService clusterBootstrapService = new ClusterBootstrapService(builder.build(), transportService, () -> {
+            throw new AssertionError("should not be called");
+        }, () -> false, vc -> { throw new AssertionError("should not be called"); });
         transportService.start();
         clusterBootstrapService.scheduleUnconfiguredBootstrap();
         deterministicTaskQueue.runAllTasks();
@@ -182,7 +178,9 @@ public void testThrowsExceptionOnDuplicates() {
                 transportService,
                 Collections::emptyList,
                 () -> false,
-                vc -> { throw new AssertionError("should not be called"); }
+                vc -> {
+                    throw new AssertionError("should not be called");
+                }
             );
         });
 
@@ -236,7 +234,9 @@ public void testDoesNotBootstrapsOnNonMasterNode() {
             transportService,
             () -> Stream.of(localNode, otherNode1, otherNode2).collect(Collectors.toList()),
             () -> false,
-            vc -> { throw new AssertionError("should not be called"); }
+            vc -> {
+                throw new AssertionError("should not be called");
+            }
         );
         assertWarnings(CLUSTER_SETTING_DEPRECATED_MESSAGE);
         transportService.start();
@@ -250,7 +250,9 @@ public void testDoesNotBootstrapsIfLocalNodeNotInInitialMasterNodes() {
             transportService,
             () -> Stream.of(localNode, otherNode1, otherNode2).collect(Collectors.toList()),
             () -> false,
-            vc -> { throw new AssertionError("should not be called"); }
+            vc -> {
+                throw new AssertionError("should not be called");
+            }
         );
         assertWarnings(CLUSTER_SETTING_DEPRECATED_MESSAGE);
         transportService.start();
@@ -264,7 +266,9 @@ public void testDoesNotBootstrapsIfNotConfigured() {
             transportService,
             () -> Stream.of(localNode, otherNode1, otherNode2).collect(Collectors.toList()),
             () -> false,
-            vc -> { throw new AssertionError("should not be called"); }
+            vc -> {
+                throw new AssertionError("should not be called");
+            }
         );
         assertWarnings(CLUSTER_SETTING_DEPRECATED_MESSAGE);
         transportService.start();
diff --git a/server/src/test/java/org/opensearch/cluster/coordination/ClusterBootstrapServiceTests.java b/server/src/test/java/org/opensearch/cluster/coordination/ClusterBootstrapServiceTests.java
index 9f9ccf34a6a9d..be7b32d4aef11 100644
--- a/server/src/test/java/org/opensearch/cluster/coordination/ClusterBootstrapServiceTests.java
+++ b/server/src/test/java/org/opensearch/cluster/coordination/ClusterBootstrapServiceTests.java
@@ -126,9 +126,9 @@ public void testBootstrapsAutomaticallyWithDefaultConfiguration() {
             settings.put(UNCONFIGURED_BOOTSTRAP_TIMEOUT_SETTING.getKey(), timeout + "ms");
         }
 
-        final AtomicReference<Supplier<Iterable<DiscoveryNode>>> discoveredNodesSupplier = new AtomicReference<>(
-            () -> { throw new AssertionError("should not be called yet"); }
-        );
+        final AtomicReference<Supplier<Iterable<DiscoveryNode>>> discoveredNodesSupplier = new AtomicReference<>(() -> {
+            throw new AssertionError("should not be called yet");
+        });
 
         final AtomicBoolean bootstrapped = new AtomicBoolean();
         ClusterBootstrapService clusterBootstrapService = new ClusterBootstrapService(
@@ -182,13 +182,9 @@ public void testDoesNothingByDefaultOnClusterManagerIneligibleNodes() {
     }
 
     private void testDoesNothingWithSettings(Settings.Builder builder) {
-        ClusterBootstrapService clusterBootstrapService = new ClusterBootstrapService(
-            builder.build(),
-            transportService,
-            () -> { throw new AssertionError("should not be called"); },
-            () -> false,
-            vc -> { throw new AssertionError("should not be called"); }
-        );
+        ClusterBootstrapService clusterBootstrapService = new ClusterBootstrapService(builder.build(), transportService, () -> {
+            throw new AssertionError("should not be called");
+        }, () -> false, vc -> { throw new AssertionError("should not be called"); });
         transportService.start();
         clusterBootstrapService.scheduleUnconfiguredBootstrap();
         deterministicTaskQueue.runAllTasks();
@@ -201,7 +197,9 @@ public void testThrowsExceptionOnDuplicates() {
                 transportService,
                 Collections::emptyList,
                 () -> false,
-                vc -> { throw new AssertionError("should not be called"); }
+                vc -> {
+                    throw new AssertionError("should not be called");
+                }
             );
         });
 
@@ -330,7 +328,9 @@ public void testDoesNotBootstrapIfNoNodesDiscovered() {
             transportService,
             Collections::emptyList,
             () -> true,
-            vc -> { throw new AssertionError("should not be called"); }
+            vc -> {
+                throw new AssertionError("should not be called");
+            }
         );
 
         transportService.start();
@@ -353,7 +353,9 @@ public void testDoesNotBootstrapIfTwoOfFiveNodesDiscovered() {
             transportService,
             () -> Stream.of(otherNode1).collect(Collectors.toList()),
             () -> false,
-            vc -> { throw new AssertionError("should not be called"); }
+            vc -> {
+                throw new AssertionError("should not be called");
+            }
         );
 
         transportService.start();
@@ -377,7 +379,9 @@ public void testDoesNotBootstrapIfThreeOfSixNodesDiscovered() {
             transportService,
             () -> Stream.of(otherNode1, otherNode2).collect(Collectors.toList()),
             () -> false,
-            vc -> { throw new AssertionError("should not be called"); }
+            vc -> {
+                throw new AssertionError("should not be called");
+            }
         );
 
         transportService.start();
@@ -393,7 +397,9 @@ public void testDoesNotBootstrapIfAlreadyBootstrapped() {
             transportService,
             () -> Stream.of(otherNode1, otherNode2).collect(Collectors.toList()),
             () -> true,
-            vc -> { throw new AssertionError("should not be called"); }
+            vc -> {
+                throw new AssertionError("should not be called");
+            }
         );
 
         transportService.start();
@@ -417,7 +423,9 @@ public void testDoesNotBootstrapsOnNonClusterManagerNode() {
             transportService,
             () -> Stream.of(localNode, otherNode1, otherNode2).collect(Collectors.toList()),
             () -> false,
-            vc -> { throw new AssertionError("should not be called"); }
+            vc -> {
+                throw new AssertionError("should not be called");
+            }
         );
         transportService.start();
         clusterBootstrapService.onFoundPeersUpdated();
@@ -430,7 +438,9 @@ public void testDoesNotBootstrapsIfLocalNodeNotInInitialClusterManagerNodes() {
             transportService,
             () -> Stream.of(localNode, otherNode1, otherNode2).collect(Collectors.toList()),
             () -> false,
-            vc -> { throw new AssertionError("should not be called"); }
+            vc -> {
+                throw new AssertionError("should not be called");
+            }
         );
         transportService.start();
         clusterBootstrapService.onFoundPeersUpdated();
@@ -443,7 +453,9 @@ public void testDoesNotBootstrapsIfNotConfigured() {
             transportService,
             () -> Stream.of(localNode, otherNode1, otherNode2).collect(Collectors.toList()),
             () -> false,
-            vc -> { throw new AssertionError("should not be called"); }
+            vc -> {
+                throw new AssertionError("should not be called");
+            }
         );
         transportService.start();
         clusterBootstrapService.scheduleUnconfiguredBootstrap();
@@ -484,7 +496,9 @@ public void testCancelsBootstrapIfRequirementMatchesMultipleNodes() {
             transportService,
             discoveredNodes::get,
             () -> false,
-            vc -> { throw new AssertionError("should not be called"); }
+            vc -> {
+                throw new AssertionError("should not be called");
+            }
         );
 
         transportService.start();
@@ -507,7 +521,9 @@ public void testCancelsBootstrapIfNodeMatchesMultipleRequirements() {
             transportService,
             discoveredNodes::get,
             () -> false,
-            vc -> { throw new AssertionError("should not be called"); }
+            vc -> {
+                throw new AssertionError("should not be called");
+            }
         );
 
         transportService.start();
@@ -593,7 +609,9 @@ public void testDoesNotJustMatchEverything() {
             transportService,
             Collections::emptyList,
             () -> false,
-            vc -> { throw new AssertionError("should not be called"); }
+            vc -> {
+                throw new AssertionError("should not be called");
+            }
         );
 
         transportService.start();
diff --git a/server/src/test/java/org/opensearch/cluster/coordination/ClusterFormationFailureHelperTests.java b/server/src/test/java/org/opensearch/cluster/coordination/ClusterFormationFailureHelperTests.java
index feede63455280..2dd5d3980a5d3 100644
--- a/server/src/test/java/org/opensearch/cluster/coordination/ClusterFormationFailureHelperTests.java
+++ b/server/src/test/java/org/opensearch/cluster/coordination/ClusterFormationFailureHelperTests.java
@@ -48,6 +48,7 @@
 
 import java.util.Arrays;
 import java.util.HashSet;
+import java.util.Set;
 import java.util.concurrent.atomic.AtomicLong;
 import java.util.stream.Collectors;
 
@@ -288,7 +289,7 @@ public void testDescriptionOnUnhealthyNodes() {
             "local",
             buildNewFakeTransportAddress(),
             emptyMap(),
-            org.opensearch.common.collect.Set.of(DiscoveryNodeRole.CLUSTER_MANAGER_ROLE),
+            Set.of(DiscoveryNodeRole.CLUSTER_MANAGER_ROLE),
             Version.CURRENT
         );
         clusterState = ClusterState.builder(ClusterName.DEFAULT)
diff --git a/server/src/test/java/org/opensearch/cluster/coordination/CoordinatorTests.java b/server/src/test/java/org/opensearch/cluster/coordination/CoordinatorTests.java
index 74c5d0fcccbed..c1a1a63a31e30 100644
--- a/server/src/test/java/org/opensearch/cluster/coordination/CoordinatorTests.java
+++ b/server/src/test/java/org/opensearch/cluster/coordination/CoordinatorTests.java
@@ -1232,11 +1232,9 @@ public void testClusterCannotFormWithFailingJoinValidation() {
                     nodes.stream().map(ClusterNode::getLocalNode).map(DiscoveryNode::getId).collect(Collectors.toSet())
                 ) == false,
                 () -> randomSubsetOf(cluster.clusterNodes)
-            ).forEach(
-                cn -> cn.extraJoinValidators.add(
-                    (discoveryNode, clusterState) -> { throw new IllegalArgumentException("join validation failed"); }
-                )
-            );
+            ).forEach(cn -> cn.extraJoinValidators.add((discoveryNode, clusterState) -> {
+                throw new IllegalArgumentException("join validation failed");
+            }));
             cluster.bootstrapIfNecessary();
             cluster.runFor(10000, "failing join validation");
             assertTrue(cluster.clusterNodes.stream().allMatch(cn -> cn.getLastAppliedClusterState().version() == 0));
diff --git a/server/src/test/java/org/opensearch/cluster/coordination/FollowersCheckerTests.java b/server/src/test/java/org/opensearch/cluster/coordination/FollowersCheckerTests.java
index 5bbbed5f4f8c0..0862597937e9d 100644
--- a/server/src/test/java/org/opensearch/cluster/coordination/FollowersCheckerTests.java
+++ b/server/src/test/java/org/opensearch/cluster/coordination/FollowersCheckerTests.java
@@ -132,7 +132,9 @@ protected void onSendRequest(long requestId, String action, TransportRequest req
             settings,
             transportService,
             fcr -> { assert false : fcr; },
-            (node, reason) -> { assert false : node; },
+            (node, reason) -> {
+                assert false : node;
+            },
             () -> new StatusInfo(StatusInfo.Status.HEALTHY, "healthy-info")
         );
 
@@ -705,7 +707,9 @@ public void testPreferClusterManagerNodes() {
             Settings.EMPTY,
             transportService,
             fcr -> { assert false : fcr; },
-            (node, reason) -> { assert false : node; },
+            (node, reason) -> {
+                assert false : node;
+            },
             () -> new StatusInfo(HEALTHY, "healthy-info")
         );
         followersChecker.setCurrentNodes(discoveryNodes);
diff --git a/server/src/test/java/org/opensearch/cluster/coordination/JoinHelperTests.java b/server/src/test/java/org/opensearch/cluster/coordination/JoinHelperTests.java
index 7b21042b2ed4a..b56abe101bd4c 100644
--- a/server/src/test/java/org/opensearch/cluster/coordination/JoinHelperTests.java
+++ b/server/src/test/java/org/opensearch/cluster/coordination/JoinHelperTests.java
@@ -86,7 +86,9 @@ public void testJoinDeduplication() {
             transportService,
             () -> 0L,
             () -> null,
-            (joinRequest, joinCallback) -> { throw new AssertionError(); },
+            (joinRequest, joinCallback) -> {
+                throw new AssertionError();
+            },
             startJoinRequest -> { throw new AssertionError(); },
             Collections.emptyList(),
             (s, p, r) -> {},
@@ -220,20 +222,11 @@ private void assertJoinValidationRejectsMismatchedClusterUUID(String actionName,
             null,
             Collections.emptySet()
         );
-        new JoinHelper(
-            Settings.EMPTY,
-            null,
-            null,
-            transportService,
-            () -> 0L,
-            () -> localClusterState,
-            (joinRequest, joinCallback) -> { throw new AssertionError(); },
-            startJoinRequest -> { throw new AssertionError(); },
-            Collections.emptyList(),
-            (s, p, r) -> {},
-            null,
-            nodeCommissioned -> {}
-        ); // registers request handler
+        new JoinHelper(Settings.EMPTY, null, null, transportService, () -> 0L, () -> localClusterState, (joinRequest, joinCallback) -> {
+            throw new AssertionError();
+        }, startJoinRequest -> { throw new AssertionError(); }, Collections.emptyList(), (s, p, r) -> {}, null, nodeCommissioned -> {}); // registers
+                                                                                                                                         // request
+                                                                                                                                         // handler
         transportService.start();
         transportService.acceptIncomingRequests();
 
@@ -282,7 +275,9 @@ public void testJoinFailureOnUnhealthyNodes() {
             transportService,
             () -> 0L,
             () -> null,
-            (joinRequest, joinCallback) -> { throw new AssertionError(); },
+            (joinRequest, joinCallback) -> {
+                throw new AssertionError();
+            },
             startJoinRequest -> { throw new AssertionError(); },
             Collections.emptyList(),
             (s, p, r) -> {},
diff --git a/server/src/test/java/org/opensearch/cluster/coordination/JoinTaskExecutorTests.java b/server/src/test/java/org/opensearch/cluster/coordination/JoinTaskExecutorTests.java
index 75b86a12c7d14..ed4c4018bfd1b 100644
--- a/server/src/test/java/org/opensearch/cluster/coordination/JoinTaskExecutorTests.java
+++ b/server/src/test/java/org/opensearch/cluster/coordination/JoinTaskExecutorTests.java
@@ -48,7 +48,6 @@
 import org.opensearch.cluster.routing.RerouteService;
 import org.opensearch.cluster.routing.allocation.AllocationService;
 import org.opensearch.common.UUIDs;
-import org.opensearch.common.collect.List;
 import org.opensearch.common.settings.Settings;
 import org.opensearch.test.OpenSearchTestCase;
 import org.opensearch.test.VersionUtils;
@@ -57,6 +56,7 @@
 import java.util.HashMap;
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 
 import static org.hamcrest.Matchers.is;
diff --git a/server/src/test/java/org/opensearch/cluster/coordination/NodeJoinTests.java b/server/src/test/java/org/opensearch/cluster/coordination/NodeJoinTests.java
index ec8d5bcf1c687..2752f57b499b3 100644
--- a/server/src/test/java/org/opensearch/cluster/coordination/NodeJoinTests.java
+++ b/server/src/test/java/org/opensearch/cluster/coordination/NodeJoinTests.java
@@ -67,6 +67,7 @@
 import org.opensearch.transport.TestTransportChannel;
 import org.opensearch.transport.Transport;
 import org.opensearch.transport.TransportRequest;
+import org.opensearch.transport.TransportRequestOptions;
 import org.opensearch.transport.TransportResponse;
 import org.opensearch.transport.TransportService;
 import org.junit.After;
@@ -218,6 +219,17 @@ protected void onSendRequest(long requestId, String action, TransportRequest req
                     super.onSendRequest(requestId, action, request, destination);
                 }
             }
+
+            @Override
+            protected void onSendRequest(
+                long requestId,
+                String action,
+                TransportRequest request,
+                DiscoveryNode destination,
+                TransportRequestOptions options
+            ) {
+                onSendRequest(requestId, action, request, destination);
+            }
         };
         final ClusterSettings clusterSettings = new ClusterSettings(Settings.EMPTY, ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
         TransportService transportService = capturingTransport.createTransportService(
@@ -517,14 +529,9 @@ public void testJoinUpdateVotingConfigExclusion() throws Exception {
             )
         );
 
-        assertTrue(
-            MasterServiceTests.discoveryState(clusterManagerService)
-                .getVotingConfigExclusions()
-                .stream()
-                .anyMatch(
-                    exclusion -> { return "knownNodeName".equals(exclusion.getNodeName()) && "newNodeId".equals(exclusion.getNodeId()); }
-                )
-        );
+        assertTrue(MasterServiceTests.discoveryState(clusterManagerService).getVotingConfigExclusions().stream().anyMatch(exclusion -> {
+            return "knownNodeName".equals(exclusion.getNodeName()) && "newNodeId".equals(exclusion.getNodeId());
+        }));
     }
 
     private ClusterState buildStateWithVotingConfigExclusion(
diff --git a/server/src/test/java/org/opensearch/cluster/coordination/OpenSearchNodeCommandTests.java b/server/src/test/java/org/opensearch/cluster/coordination/OpenSearchNodeCommandTests.java
index e88633fbf9399..242307d220381 100644
--- a/server/src/test/java/org/opensearch/cluster/coordination/OpenSearchNodeCommandTests.java
+++ b/server/src/test/java/org/opensearch/cluster/coordination/OpenSearchNodeCommandTests.java
@@ -39,7 +39,6 @@
 import org.opensearch.cluster.metadata.Metadata;
 import org.opensearch.common.UUIDs;
 import org.opensearch.common.bytes.BytesReference;
-import org.opensearch.common.collect.List;
 import org.opensearch.common.xcontent.NamedXContentRegistry;
 import org.opensearch.common.xcontent.XContentBuilder;
 import org.opensearch.common.xcontent.XContentParser;
@@ -50,6 +49,7 @@
 
 import java.io.IOException;
 import java.nio.file.Path;
+import java.util.List;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
diff --git a/server/src/test/java/org/opensearch/cluster/decommission/DecommissionControllerTests.java b/server/src/test/java/org/opensearch/cluster/decommission/DecommissionControllerTests.java
index 9736355629fd9..7108e06fe39fc 100644
--- a/server/src/test/java/org/opensearch/cluster/decommission/DecommissionControllerTests.java
+++ b/server/src/test/java/org/opensearch/cluster/decommission/DecommissionControllerTests.java
@@ -40,6 +40,7 @@
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.CountDownLatch;
@@ -265,7 +266,7 @@ public void onFailure(Exception e) {
 
     private ClusterState addNodes(ClusterState clusterState, String zone, String... nodeIds) {
         DiscoveryNodes.Builder nodeBuilder = DiscoveryNodes.builder(clusterState.nodes());
-        org.opensearch.common.collect.List.of(nodeIds).forEach(nodeId -> nodeBuilder.add(newNode(nodeId, singletonMap("zone", zone))));
+        List.of(nodeIds).forEach(nodeId -> nodeBuilder.add(newNode(nodeId, singletonMap("zone", zone))));
         clusterState = ClusterState.builder(clusterState).nodes(nodeBuilder).build();
         return clusterState;
     }
diff --git a/server/src/test/java/org/opensearch/cluster/decommission/DecommissionServiceTests.java b/server/src/test/java/org/opensearch/cluster/decommission/DecommissionServiceTests.java
index c1ce0a3534720..d4bc474ae0c10 100644
--- a/server/src/test/java/org/opensearch/cluster/decommission/DecommissionServiceTests.java
+++ b/server/src/test/java/org/opensearch/cluster/decommission/DecommissionServiceTests.java
@@ -42,6 +42,7 @@
 
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.CountDownLatch;
@@ -421,15 +422,14 @@ private void setWeightedRoutingWeights(Map<String, Double> weights) {
 
     private ClusterState addDataNodes(ClusterState clusterState, String zone, String... nodeIds) {
         DiscoveryNodes.Builder nodeBuilder = DiscoveryNodes.builder(clusterState.nodes());
-        org.opensearch.common.collect.List.of(nodeIds).forEach(nodeId -> nodeBuilder.add(newDataNode(nodeId, singletonMap("zone", zone))));
+        List.of(nodeIds).forEach(nodeId -> nodeBuilder.add(newDataNode(nodeId, singletonMap("zone", zone))));
         clusterState = ClusterState.builder(clusterState).nodes(nodeBuilder).build();
         return clusterState;
     }
 
     private ClusterState addClusterManagerNodes(ClusterState clusterState, String zone, String... nodeIds) {
         DiscoveryNodes.Builder nodeBuilder = DiscoveryNodes.builder(clusterState.nodes());
-        org.opensearch.common.collect.List.of(nodeIds)
-            .forEach(nodeId -> nodeBuilder.add(newClusterManagerNode(nodeId, singletonMap("zone", zone))));
+        List.of(nodeIds).forEach(nodeId -> nodeBuilder.add(newClusterManagerNode(nodeId, singletonMap("zone", zone))));
         clusterState = ClusterState.builder(clusterState).nodes(nodeBuilder).build();
         return clusterState;
     }
@@ -474,7 +474,7 @@ private static DiscoveryNode newClusterManagerNode(String nodeId, Map<String, St
 
     private ClusterState removeNodes(ClusterState clusterState, String... nodeIds) {
         DiscoveryNodes.Builder nodeBuilder = DiscoveryNodes.builder(clusterState.getNodes());
-        org.opensearch.common.collect.List.of(nodeIds).forEach(nodeBuilder::remove);
+        List.of(nodeIds).forEach(nodeBuilder::remove);
         return allocationService.disassociateDeadNodes(ClusterState.builder(clusterState).nodes(nodeBuilder).build(), false, "test");
     }
 }
diff --git a/server/src/test/java/org/opensearch/cluster/metadata/IndexNameExpressionResolverTests.java b/server/src/test/java/org/opensearch/cluster/metadata/IndexNameExpressionResolverTests.java
index e736e27e5aa44..52a2663f173a7 100644
--- a/server/src/test/java/org/opensearch/cluster/metadata/IndexNameExpressionResolverTests.java
+++ b/server/src/test/java/org/opensearch/cluster/metadata/IndexNameExpressionResolverTests.java
@@ -2020,14 +2020,7 @@ public void testIndicesAliasesRequestTargetDataStreams() {
 
         Metadata.Builder mdBuilder = Metadata.builder()
             .put(backingIndex, false)
-            .put(
-                new DataStream(
-                    dataStreamName,
-                    createTimestampField("@timestamp"),
-                    org.opensearch.common.collect.List.of(backingIndex.getIndex()),
-                    1
-                )
-            );
+            .put(new DataStream(dataStreamName, createTimestampField("@timestamp"), List.of(backingIndex.getIndex()), 1));
         ClusterState state = ClusterState.builder(new ClusterName("_name")).metadata(mdBuilder).build();
 
         {
@@ -2248,14 +2241,7 @@ public void testDataStreams() {
         Metadata.Builder mdBuilder = Metadata.builder()
             .put(index1, false)
             .put(index2, false)
-            .put(
-                new DataStream(
-                    dataStreamName,
-                    createTimestampField("@timestamp"),
-                    org.opensearch.common.collect.List.of(index1.getIndex(), index2.getIndex()),
-                    2
-                )
-            );
+            .put(new DataStream(dataStreamName, createTimestampField("@timestamp"), List.of(index1.getIndex(), index2.getIndex()), 2));
         ClusterState state = ClusterState.builder(new ClusterName("_name")).metadata(mdBuilder).build();
 
         {
@@ -2347,20 +2333,8 @@ public void testDataStreamsWithWildcardExpression() {
             .put(index2, false)
             .put(index3, false)
             .put(index4, false)
-            .put(
-                new DataStream(
-                    dataStream1,
-                    createTimestampField("@timestamp"),
-                    org.opensearch.common.collect.List.of(index1.getIndex(), index2.getIndex())
-                )
-            )
-            .put(
-                new DataStream(
-                    dataStream2,
-                    createTimestampField("@timestamp"),
-                    org.opensearch.common.collect.List.of(index3.getIndex(), index4.getIndex())
-                )
-            );
+            .put(new DataStream(dataStream1, createTimestampField("@timestamp"), List.of(index1.getIndex(), index2.getIndex())))
+            .put(new DataStream(dataStream2, createTimestampField("@timestamp"), List.of(index3.getIndex(), index4.getIndex())));
 
         ClusterState state = ClusterState.builder(new ClusterName("_name")).metadata(mdBuilder).build();
         {
@@ -2417,20 +2391,8 @@ public void testDataStreamsWithClosedBackingIndicesAndWildcardExpressions() {
             .put(index2, false)
             .put(index3, false)
             .put(index4, false)
-            .put(
-                new DataStream(
-                    dataStream1,
-                    createTimestampField("@timestamp"),
-                    org.opensearch.common.collect.List.of(index1.getIndex(), index2.getIndex())
-                )
-            )
-            .put(
-                new DataStream(
-                    dataStream2,
-                    createTimestampField("@timestamp"),
-                    org.opensearch.common.collect.List.of(index3.getIndex(), index4.getIndex())
-                )
-            );
+            .put(new DataStream(dataStream1, createTimestampField("@timestamp"), List.of(index1.getIndex(), index2.getIndex())))
+            .put(new DataStream(dataStream2, createTimestampField("@timestamp"), List.of(index3.getIndex(), index4.getIndex())));
 
         ClusterState state = ClusterState.builder(new ClusterName("_name")).metadata(mdBuilder).build();
         IndicesOptions indicesOptions = IndicesOptions.STRICT_EXPAND_OPEN;
diff --git a/server/src/test/java/org/opensearch/cluster/metadata/MetadataCreateIndexServiceTests.java b/server/src/test/java/org/opensearch/cluster/metadata/MetadataCreateIndexServiceTests.java
index a1e40e55b09cf..3a42fd2b467f8 100644
--- a/server/src/test/java/org/opensearch/cluster/metadata/MetadataCreateIndexServiceTests.java
+++ b/server/src/test/java/org/opensearch/cluster/metadata/MetadataCreateIndexServiceTests.java
@@ -735,9 +735,9 @@ public void testParseMappingsAppliesDataFromTemplateAndRequest() throws Exceptio
     }
 
     public void testAggregateSettingsAppliesSettingsFromTemplatesAndRequest() {
-        IndexTemplateMetadata templateMetadata = addMatchingTemplate(
-            builder -> { builder.settings(Settings.builder().put("template_setting", "value1")); }
-        );
+        IndexTemplateMetadata templateMetadata = addMatchingTemplate(builder -> {
+            builder.settings(Settings.builder().put("template_setting", "value1"));
+        });
         ImmutableOpenMap.Builder<String, IndexTemplateMetadata> templatesBuilder = ImmutableOpenMap.builder();
         templatesBuilder.put("template_1", templateMetadata);
         Metadata metadata = new Metadata.Builder().templates(templatesBuilder.build()).build();
@@ -957,13 +957,7 @@ public void testClusterStateCreateIndexThrowsWriteIndexValidationException() thr
         assertThat(
             expectThrows(
                 IllegalStateException.class,
-                () -> clusterStateCreateIndex(
-                    currentClusterState,
-                    org.opensearch.common.collect.Set.of(),
-                    newIndex,
-                    (state, reason) -> state,
-                    null
-                )
+                () -> clusterStateCreateIndex(currentClusterState, Set.of(), newIndex, (state, reason) -> state, null)
             ).getMessage(),
             startsWith("alias [alias1] has more than one write index [")
         );
@@ -988,7 +982,7 @@ public void testClusterStateCreateIndex() {
 
         ClusterState updatedClusterState = clusterStateCreateIndex(
             currentClusterState,
-            org.opensearch.common.collect.Set.of(INDEX_READ_ONLY_BLOCK),
+            Set.of(INDEX_READ_ONLY_BLOCK),
             newIndexMetadata,
             rerouteRoutingTable,
             null
@@ -1027,7 +1021,7 @@ public void testClusterStateCreateIndexWithMetadataTransaction() {
 
         ClusterState updatedClusterState = clusterStateCreateIndex(
             currentClusterState,
-            org.opensearch.common.collect.Set.of(INDEX_READ_ONLY_BLOCK),
+            Set.of(INDEX_READ_ONLY_BLOCK),
             newIndexMetadata,
             (clusterState, y) -> clusterState,
             metadataTransformer
diff --git a/server/src/test/java/org/opensearch/cluster/metadata/MetadataDeleteIndexServiceTests.java b/server/src/test/java/org/opensearch/cluster/metadata/MetadataDeleteIndexServiceTests.java
index 5caea9f5bf674..dbff833cfee60 100644
--- a/server/src/test/java/org/opensearch/cluster/metadata/MetadataDeleteIndexServiceTests.java
+++ b/server/src/test/java/org/opensearch/cluster/metadata/MetadataDeleteIndexServiceTests.java
@@ -98,7 +98,7 @@ public void testDeleteSnapshotting() {
         String index = randomAlphaOfLength(5);
         Snapshot snapshot = new Snapshot("doesn't matter", new SnapshotId("snapshot name", "snapshot uuid"));
         SnapshotsInProgress snaps = SnapshotsInProgress.of(
-            org.opensearch.common.collect.List.of(
+            List.of(
                 new SnapshotsInProgress.Entry(
                     snapshot,
                     true,
@@ -153,14 +153,14 @@ public void testDeleteBackingIndexForDataStream() {
         int numBackingIndices = randomIntBetween(2, 5);
         String dataStreamName = randomAlphaOfLength(6).toLowerCase(Locale.ROOT);
         ClusterState before = DataStreamTestHelper.getClusterStateWithDataStreams(
-            org.opensearch.common.collect.List.of(new Tuple<>(dataStreamName, numBackingIndices)),
-            org.opensearch.common.collect.List.of()
+            List.of(new Tuple<>(dataStreamName, numBackingIndices)),
+            List.of()
         );
 
         int numIndexToDelete = randomIntBetween(1, numBackingIndices - 1);
 
         Index indexToDelete = before.metadata().index(DataStream.getDefaultBackingIndexName(dataStreamName, numIndexToDelete)).getIndex();
-        ClusterState after = service.deleteIndices(before, org.opensearch.common.collect.Set.of(indexToDelete));
+        ClusterState after = service.deleteIndices(before, Set.of(indexToDelete));
 
         assertThat(after.metadata().getIndices().get(indexToDelete.getName()), IsNull.nullValue());
         assertThat(after.metadata().getIndices().size(), equalTo(numBackingIndices - 1));
@@ -175,8 +175,8 @@ public void testDeleteMultipleBackingIndexForDataStream() {
         int numBackingIndicesToDelete = randomIntBetween(2, numBackingIndices - 1);
         String dataStreamName = randomAlphaOfLength(6).toLowerCase(Locale.ROOT);
         ClusterState before = DataStreamTestHelper.getClusterStateWithDataStreams(
-            org.opensearch.common.collect.List.of(new Tuple<>(dataStreamName, numBackingIndices)),
-            org.opensearch.common.collect.List.of()
+            List.of(new Tuple<>(dataStreamName, numBackingIndices)),
+            List.of()
         );
 
         List<Integer> indexNumbersToDelete = randomSubsetOf(
@@ -204,15 +204,12 @@ public void testDeleteCurrentWriteIndexForDataStream() {
         int numBackingIndices = randomIntBetween(1, 5);
         String dataStreamName = randomAlphaOfLength(6).toLowerCase(Locale.ROOT);
         ClusterState before = DataStreamTestHelper.getClusterStateWithDataStreams(
-            org.opensearch.common.collect.List.of(new Tuple<>(dataStreamName, numBackingIndices)),
-            org.opensearch.common.collect.List.of()
+            List.of(new Tuple<>(dataStreamName, numBackingIndices)),
+            List.of()
         );
 
         Index indexToDelete = before.metadata().index(DataStream.getDefaultBackingIndexName(dataStreamName, numBackingIndices)).getIndex();
-        Exception e = expectThrows(
-            IllegalArgumentException.class,
-            () -> service.deleteIndices(before, org.opensearch.common.collect.Set.of(indexToDelete))
-        );
+        Exception e = expectThrows(IllegalArgumentException.class, () -> service.deleteIndices(before, Set.of(indexToDelete)));
 
         assertThat(
             e.getMessage(),
diff --git a/server/src/test/java/org/opensearch/cluster/metadata/MetadataIndexStateServiceTests.java b/server/src/test/java/org/opensearch/cluster/metadata/MetadataIndexStateServiceTests.java
index fb01a493ff7c3..5d476b2dbdca5 100644
--- a/server/src/test/java/org/opensearch/cluster/metadata/MetadataIndexStateServiceTests.java
+++ b/server/src/test/java/org/opensearch/cluster/metadata/MetadataIndexStateServiceTests.java
@@ -450,10 +450,7 @@ public void testCloseCurrentWriteIndexForDataStream() {
             dataStreamsToCreate.add(new Tuple<>(dataStreamName, numBackingIndices));
             writeIndices.add(DataStream.getDefaultBackingIndexName(dataStreamName, numBackingIndices));
         }
-        ClusterState cs = DeleteDataStreamRequestTests.getClusterStateWithDataStreams(
-            dataStreamsToCreate,
-            org.opensearch.common.collect.List.of()
-        );
+        ClusterState cs = DeleteDataStreamRequestTests.getClusterStateWithDataStreams(dataStreamsToCreate, List.of());
 
         ClusterService clusterService = mock(ClusterService.class);
         when(clusterService.state()).thenReturn(cs);
diff --git a/server/src/test/java/org/opensearch/cluster/metadata/MetadataIndexTemplateServiceTests.java b/server/src/test/java/org/opensearch/cluster/metadata/MetadataIndexTemplateServiceTests.java
index d54b7e9389bf7..26f711bba14f9 100644
--- a/server/src/test/java/org/opensearch/cluster/metadata/MetadataIndexTemplateServiceTests.java
+++ b/server/src/test/java/org/opensearch/cluster/metadata/MetadataIndexTemplateServiceTests.java
@@ -429,9 +429,9 @@ public void testUpdateComponentTemplateWithIndexHiddenSetting() throws Exception
         assertNotNull(state.metadata().componentTemplates().get("foo"));
 
         ComposableIndexTemplate firstGlobalIndexTemplate = new ComposableIndexTemplate(
-            org.opensearch.common.collect.List.of("*"),
+            List.of("*"),
             template,
-            org.opensearch.common.collect.List.of("foo"),
+            List.of("foo"),
             1L,
             null,
             null,
@@ -440,9 +440,9 @@ public void testUpdateComponentTemplateWithIndexHiddenSetting() throws Exception
         state = metadataIndexTemplateService.addIndexTemplateV2(state, true, "globalindextemplate1", firstGlobalIndexTemplate);
 
         ComposableIndexTemplate secondGlobalIndexTemplate = new ComposableIndexTemplate(
-            org.opensearch.common.collect.List.of("*"),
+            List.of("*"),
             template,
-            org.opensearch.common.collect.List.of("foo"),
+            List.of("foo"),
             2L,
             null,
             null,
@@ -451,9 +451,9 @@ public void testUpdateComponentTemplateWithIndexHiddenSetting() throws Exception
         state = metadataIndexTemplateService.addIndexTemplateV2(state, true, "globalindextemplate2", secondGlobalIndexTemplate);
 
         ComposableIndexTemplate fooPatternIndexTemplate = new ComposableIndexTemplate(
-            org.opensearch.common.collect.List.of("foo-*"),
+            List.of("foo-*"),
             template,
-            org.opensearch.common.collect.List.of("foo"),
+            List.of("foo"),
             3L,
             null,
             null,
@@ -616,9 +616,9 @@ public void onFailure(Exception e) {
         waitToCreateComponentTemplate.await(10, TimeUnit.SECONDS);
 
         ComposableIndexTemplate globalIndexTemplate = new ComposableIndexTemplate(
-            org.opensearch.common.collect.List.of("*"),
+            List.of("*"),
             null,
-            org.opensearch.common.collect.List.of("ct-with-index-hidden-setting"),
+            List.of("ct-with-index-hidden-setting"),
             null,
             null,
             null,
@@ -941,9 +941,9 @@ public void testFindV2InvalidGlobalTemplate() {
         try {
             // add an invalid global template that specifies the `index.hidden` setting
             ComposableIndexTemplate invalidGlobalTemplate = new ComposableIndexTemplate(
-                org.opensearch.common.collect.List.of("*"),
+                List.of("*"),
                 templateWithHiddenSetting,
-                org.opensearch.common.collect.List.of("ct"),
+                List.of("ct"),
                 5L,
                 1L,
                 null,
@@ -952,9 +952,7 @@ public void testFindV2InvalidGlobalTemplate() {
             Metadata invalidGlobalTemplateMetadata = Metadata.builder()
                 .putCustom(
                     ComposableIndexTemplateMetadata.TYPE,
-                    new ComposableIndexTemplateMetadata(
-                        org.opensearch.common.collect.Map.of("invalid_global_template", invalidGlobalTemplate)
-                    )
+                    new ComposableIndexTemplateMetadata(Map.of("invalid_global_template", invalidGlobalTemplate))
                 )
                 .build();
 
@@ -1213,7 +1211,7 @@ public void testDefinedTimestampMappingIsAddedForDataStreamTemplates() throws Ex
 
         {
             ComposableIndexTemplate it = new ComposableIndexTemplate(
-                org.opensearch.common.collect.List.of("logs*"),
+                List.of("logs*"),
                 new Template(
                     null,
                     new CompressedXContent(
@@ -1227,7 +1225,7 @@ public void testDefinedTimestampMappingIsAddedForDataStreamTemplates() throws Ex
                     ),
                     null
                 ),
-                org.opensearch.common.collect.List.of("ct1"),
+                List.of("ct1"),
                 0L,
                 1L,
                 null,
@@ -1245,7 +1243,7 @@ public void testDefinedTimestampMappingIsAddedForDataStreamTemplates() throws Ex
             assertThat(mappings.size(), equalTo(4));
             List<Map<String, Object>> parsedMappings = mappings.stream().map(m -> {
                 try {
-                    return MapperService.parseMapping(new NamedXContentRegistry(org.opensearch.common.collect.List.of()), m.string());
+                    return MapperService.parseMapping(new NamedXContentRegistry(List.of()), m.string());
                 } catch (Exception e) {
                     logger.error(e);
                     fail("failed to parse mappings: " + m.string());
@@ -1253,38 +1251,23 @@ public void testDefinedTimestampMappingIsAddedForDataStreamTemplates() throws Ex
                 }
             }).collect(Collectors.toList());
 
-            Map<String, Object> firstParsedMapping = org.opensearch.common.collect.Map.of(
+            Map<String, Object> firstParsedMapping = Map.of(
                 "_doc",
-                org.opensearch.common.collect.Map.of(
-                    "properties",
-                    org.opensearch.common.collect.Map.of(TIMESTAMP_FIELD.getName(), org.opensearch.common.collect.Map.of("type", "date"))
-                )
+                Map.of("properties", Map.of(TIMESTAMP_FIELD.getName(), Map.of("type", "date")))
             );
             assertThat(parsedMappings.get(0), equalTo(firstParsedMapping));
 
-            Map<String, Object> secondMapping = org.opensearch.common.collect.Map.of(
-                "_doc",
-                org.opensearch.common.collect.Map.of(
-                    "properties",
-                    org.opensearch.common.collect.Map.of("field1", org.opensearch.common.collect.Map.of("type", "keyword"))
-                )
-            );
+            Map<String, Object> secondMapping = Map.of("_doc", Map.of("properties", Map.of("field1", Map.of("type", "keyword"))));
             assertThat(parsedMappings.get(1), equalTo(secondMapping));
 
-            Map<String, Object> thirdMapping = org.opensearch.common.collect.Map.of(
-                "_doc",
-                org.opensearch.common.collect.Map.of(
-                    "properties",
-                    org.opensearch.common.collect.Map.of("field2", org.opensearch.common.collect.Map.of("type", "integer"))
-                )
-            );
+            Map<String, Object> thirdMapping = Map.of("_doc", Map.of("properties", Map.of("field2", Map.of("type", "integer"))));
             assertThat(parsedMappings.get(2), equalTo(thirdMapping));
         }
 
         {
             // indices matched by templates without the data stream field defined don't get the default @timestamp mapping
             ComposableIndexTemplate it = new ComposableIndexTemplate(
-                org.opensearch.common.collect.List.of("timeseries*"),
+                List.of("timeseries*"),
                 new Template(
                     null,
                     new CompressedXContent(
@@ -1298,7 +1281,7 @@ public void testDefinedTimestampMappingIsAddedForDataStreamTemplates() throws Ex
                     ),
                     null
                 ),
-                org.opensearch.common.collect.List.of("ct1"),
+                List.of("ct1"),
                 0L,
                 1L,
                 null,
@@ -1312,7 +1295,7 @@ public void testDefinedTimestampMappingIsAddedForDataStreamTemplates() throws Ex
             assertThat(mappings.size(), equalTo(2));
             List<Map<String, Object>> parsedMappings = mappings.stream().map(m -> {
                 try {
-                    return MapperService.parseMapping(new NamedXContentRegistry(org.opensearch.common.collect.List.of()), m.string());
+                    return MapperService.parseMapping(new NamedXContentRegistry(List.of()), m.string());
                 } catch (Exception e) {
                     logger.error(e);
                     fail("failed to parse mappings: " + m.string());
@@ -1320,22 +1303,10 @@ public void testDefinedTimestampMappingIsAddedForDataStreamTemplates() throws Ex
                 }
             }).collect(Collectors.toList());
 
-            Map<String, Object> firstMapping = org.opensearch.common.collect.Map.of(
-                "_doc",
-                org.opensearch.common.collect.Map.of(
-                    "properties",
-                    org.opensearch.common.collect.Map.of("field1", org.opensearch.common.collect.Map.of("type", "keyword"))
-                )
-            );
+            Map<String, Object> firstMapping = Map.of("_doc", Map.of("properties", Map.of("field1", Map.of("type", "keyword"))));
             assertThat(parsedMappings.get(0), equalTo(firstMapping));
 
-            Map<String, Object> secondMapping = org.opensearch.common.collect.Map.of(
-                "_doc",
-                org.opensearch.common.collect.Map.of(
-                    "properties",
-                    org.opensearch.common.collect.Map.of("field2", org.opensearch.common.collect.Map.of("type", "integer"))
-                )
-            );
+            Map<String, Object> secondMapping = Map.of("_doc", Map.of("properties", Map.of("field2", Map.of("type", "integer"))));
             assertThat(parsedMappings.get(1), equalTo(secondMapping));
 
             // a default @timestamp mapping will not be added if the matching template doesn't have the data stream field configured, even
@@ -1350,7 +1321,7 @@ public void testDefinedTimestampMappingIsAddedForDataStreamTemplates() throws Ex
             assertThat(mappings.size(), equalTo(2));
             parsedMappings = mappings.stream().map(m -> {
                 try {
-                    return MapperService.parseMapping(new NamedXContentRegistry(org.opensearch.common.collect.List.of()), m.string());
+                    return MapperService.parseMapping(new NamedXContentRegistry(List.of()), m.string());
                 } catch (Exception e) {
                     logger.error(e);
                     fail("failed to parse mappings: " + m.string());
@@ -1358,22 +1329,10 @@ public void testDefinedTimestampMappingIsAddedForDataStreamTemplates() throws Ex
                 }
             }).collect(Collectors.toList());
 
-            firstMapping = org.opensearch.common.collect.Map.of(
-                "_doc",
-                org.opensearch.common.collect.Map.of(
-                    "properties",
-                    org.opensearch.common.collect.Map.of("field1", org.opensearch.common.collect.Map.of("type", "keyword"))
-                )
-            );
+            firstMapping = Map.of("_doc", Map.of("properties", Map.of("field1", Map.of("type", "keyword"))));
             assertThat(parsedMappings.get(0), equalTo(firstMapping));
 
-            secondMapping = org.opensearch.common.collect.Map.of(
-                "_doc",
-                org.opensearch.common.collect.Map.of(
-                    "properties",
-                    org.opensearch.common.collect.Map.of("field2", org.opensearch.common.collect.Map.of("type", "integer"))
-                )
-            );
+            secondMapping = Map.of("_doc", Map.of("properties", Map.of("field2", Map.of("type", "integer"))));
             assertThat(parsedMappings.get(1), equalTo(secondMapping));
         }
     }
@@ -1404,9 +1363,9 @@ public void testUserDefinedMappingTakesPrecedenceOverDefault() throws Exception
 
             state = service.addComponentTemplate(state, true, "ct1", ct1);
             ComposableIndexTemplate it = new ComposableIndexTemplate(
-                org.opensearch.common.collect.List.of("logs*"),
+                List.of("logs*"),
                 null,
-                org.opensearch.common.collect.List.of("ct1"),
+                List.of("ct1"),
                 0L,
                 1L,
                 null,
@@ -1424,7 +1383,7 @@ public void testUserDefinedMappingTakesPrecedenceOverDefault() throws Exception
             assertThat(mappings.size(), equalTo(3));
             List<Map<String, Object>> parsedMappings = mappings.stream().map(m -> {
                 try {
-                    return MapperService.parseMapping(new NamedXContentRegistry(org.opensearch.common.collect.List.of()), m.string());
+                    return MapperService.parseMapping(new NamedXContentRegistry(List.of()), m.string());
                 } catch (Exception e) {
                     logger.error(e);
                     fail("failed to parse mappings: " + m.string());
@@ -1432,24 +1391,15 @@ public void testUserDefinedMappingTakesPrecedenceOverDefault() throws Exception
                 }
             }).collect(Collectors.toList());
 
-            Map<String, Object> firstMapping = org.opensearch.common.collect.Map.of(
+            Map<String, Object> firstMapping = Map.of(
                 "_doc",
-                org.opensearch.common.collect.Map.of(
-                    "properties",
-                    org.opensearch.common.collect.Map.of(TIMESTAMP_FIELD.getName(), org.opensearch.common.collect.Map.of("type", "date"))
-                )
+                Map.of("properties", Map.of(TIMESTAMP_FIELD.getName(), Map.of("type", "date")))
             );
             assertThat(parsedMappings.get(0), equalTo(firstMapping));
 
-            Map<String, Object> secondMapping = org.opensearch.common.collect.Map.of(
+            Map<String, Object> secondMapping = Map.of(
                 "_doc",
-                org.opensearch.common.collect.Map.of(
-                    "properties",
-                    org.opensearch.common.collect.Map.of(
-                        TIMESTAMP_FIELD.getName(),
-                        org.opensearch.common.collect.Map.of("type", "date_nanos")
-                    )
-                )
+                Map.of("properties", Map.of(TIMESTAMP_FIELD.getName(), Map.of("type", "date_nanos")))
             );
             assertThat(parsedMappings.get(1), equalTo(secondMapping));
         }
@@ -1470,7 +1420,7 @@ public void testUserDefinedMappingTakesPrecedenceOverDefault() throws Exception
                 null
             );
             ComposableIndexTemplate it = new ComposableIndexTemplate(
-                org.opensearch.common.collect.List.of("timeseries*"),
+                List.of("timeseries*"),
                 template,
                 null,
                 0L,
@@ -1490,31 +1440,22 @@ public void testUserDefinedMappingTakesPrecedenceOverDefault() throws Exception
             assertThat(mappings.size(), equalTo(3));
             List<Map<String, Object>> parsedMappings = mappings.stream().map(m -> {
                 try {
-                    return MapperService.parseMapping(new NamedXContentRegistry(org.opensearch.common.collect.List.of()), m.string());
+                    return MapperService.parseMapping(new NamedXContentRegistry(List.of()), m.string());
                 } catch (Exception e) {
                     logger.error(e);
                     fail("failed to parse mappings: " + m.string());
                     return null;
                 }
             }).collect(Collectors.toList());
-            Map<String, Object> firstMapping = org.opensearch.common.collect.Map.of(
+            Map<String, Object> firstMapping = Map.of(
                 "_doc",
-                org.opensearch.common.collect.Map.of(
-                    "properties",
-                    org.opensearch.common.collect.Map.of(TIMESTAMP_FIELD.getName(), org.opensearch.common.collect.Map.of("type", "date"))
-                )
+                Map.of("properties", Map.of(TIMESTAMP_FIELD.getName(), Map.of("type", "date")))
             );
             assertThat(parsedMappings.get(0), equalTo(firstMapping));
 
-            Map<String, Object> secondMapping = org.opensearch.common.collect.Map.of(
+            Map<String, Object> secondMapping = Map.of(
                 "_doc",
-                org.opensearch.common.collect.Map.of(
-                    "properties",
-                    org.opensearch.common.collect.Map.of(
-                        TIMESTAMP_FIELD.getName(),
-                        org.opensearch.common.collect.Map.of("type", "date_nanos")
-                    )
-                )
+                Map.of("properties", Map.of(TIMESTAMP_FIELD.getName(), Map.of("type", "date_nanos")))
             );
             assertThat(parsedMappings.get(1), equalTo(secondMapping));
         }
diff --git a/server/src/test/java/org/opensearch/cluster/metadata/MetadataTests.java b/server/src/test/java/org/opensearch/cluster/metadata/MetadataTests.java
index 4e7502ada661f..7870423a88476 100644
--- a/server/src/test/java/org/opensearch/cluster/metadata/MetadataTests.java
+++ b/server/src/test/java/org/opensearch/cluster/metadata/MetadataTests.java
@@ -1065,7 +1065,7 @@ public void testBuilderRejectsDataStreamThatConflictsWithIndex() {
                 IndexMetadata.builder(dataStreamName).settings(settings(Version.CURRENT)).numberOfShards(1).numberOfReplicas(1).build(),
                 false
             )
-            .put(new DataStream(dataStreamName, createTimestampField("@timestamp"), org.opensearch.common.collect.List.of(idx.getIndex())));
+            .put(new DataStream(dataStreamName, createTimestampField("@timestamp"), List.of(idx.getIndex())));
 
         IllegalStateException e = expectThrows(IllegalStateException.class, b::build);
         assertThat(
@@ -1084,7 +1084,7 @@ public void testBuilderRejectsDataStreamThatConflictsWithAlias() {
         IndexMetadata idx = createFirstBackingIndex(dataStreamName).putAlias(AliasMetadata.builder(dataStreamName).build()).build();
         Metadata.Builder b = Metadata.builder()
             .put(idx, false)
-            .put(new DataStream(dataStreamName, createTimestampField("@timestamp"), org.opensearch.common.collect.List.of(idx.getIndex())));
+            .put(new DataStream(dataStreamName, createTimestampField("@timestamp"), List.of(idx.getIndex())));
 
         IllegalStateException e = expectThrows(IllegalStateException.class, b::build);
         assertThat(
@@ -1107,13 +1107,7 @@ public void testBuilderRejectsDataStreamWithConflictingBackingIndices() {
         Metadata.Builder b = Metadata.builder()
             .put(validIdx, false)
             .put(invalidIdx, false)
-            .put(
-                new DataStream(
-                    dataStreamName,
-                    createTimestampField("@timestamp"),
-                    org.opensearch.common.collect.List.of(validIdx.getIndex())
-                )
-            );
+            .put(new DataStream(dataStreamName, createTimestampField("@timestamp"), List.of(validIdx.getIndex())));
 
         IllegalStateException e = expectThrows(IllegalStateException.class, b::build);
         assertThat(
@@ -1134,7 +1128,7 @@ public void testBuilderRejectsDataStreamWithConflictingBackingAlias() {
         IndexMetadata idx = createFirstBackingIndex(dataStreamName).putAlias(new AliasMetadata.Builder(conflictingName)).build();
         Metadata.Builder b = Metadata.builder()
             .put(idx, false)
-            .put(new DataStream(dataStreamName, createTimestampField("@timestamp"), org.opensearch.common.collect.List.of(idx.getIndex())));
+            .put(new DataStream(dataStreamName, createTimestampField("@timestamp"), List.of(idx.getIndex())));
 
         IllegalStateException e = expectThrows(IllegalStateException.class, b::build);
         assertThat(
@@ -1269,7 +1263,7 @@ public void testValidateDataStreamsThrowsExceptionOnConflict() {
         Index index = standaloneIndexConflictingWithBackingIndices.getIndex();
         indicesLookup.put(index.getName(), new IndexAbstraction.Index(standaloneIndexConflictingWithBackingIndices, null));
 
-        DataStreamMetadata dataStreamMetadata = new DataStreamMetadata(org.opensearch.common.collect.Map.of(dataStreamName, dataStream));
+        DataStreamMetadata dataStreamMetadata = new DataStreamMetadata(Map.of(dataStreamName, dataStream));
 
         IllegalStateException illegalStateException = expectThrows(
             IllegalStateException.class,
@@ -1362,7 +1356,7 @@ public void testValidateDataStreamsAllowsPrefixedBackingIndices() {
                 indicesLookup.put(indexMeta.getIndex().getName(), new IndexAbstraction.Index(indexMeta, dataStreamAbstraction));
             }
         }
-        DataStreamMetadata dataStreamMetadata = new DataStreamMetadata(org.opensearch.common.collect.Map.of(dataStreamName, dataStream));
+        DataStreamMetadata dataStreamMetadata = new DataStreamMetadata(Map.of(dataStreamName, dataStream));
 
         // prefixed indices with a lower generation than the data stream's generation are allowed even if the non-prefixed, matching the
         // data stream backing indices naming pattern, indices are already in the system
diff --git a/server/src/test/java/org/opensearch/cluster/metadata/ToAndFromJsonMetadataTests.java b/server/src/test/java/org/opensearch/cluster/metadata/ToAndFromJsonMetadataTests.java
index 253018d7f569f..c0210fe269e59 100644
--- a/server/src/test/java/org/opensearch/cluster/metadata/ToAndFromJsonMetadataTests.java
+++ b/server/src/test/java/org/opensearch/cluster/metadata/ToAndFromJsonMetadataTests.java
@@ -51,6 +51,7 @@
 import java.util.EnumSet;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 
 import static org.opensearch.cluster.DataStreamTestHelper.createFirstBackingIndex;
@@ -128,8 +129,8 @@ public void testSimpleJsonFromAndTo() throws IOException {
             )
             .put(idx1, false)
             .put(idx2, false)
-            .put(new DataStream("data-stream1", createTimestampField("@timestamp"), org.opensearch.common.collect.List.of(idx1.getIndex())))
-            .put(new DataStream("data-stream2", createTimestampField("@timestamp"), org.opensearch.common.collect.List.of(idx2.getIndex())))
+            .put(new DataStream("data-stream1", createTimestampField("@timestamp"), List.of(idx1.getIndex())))
+            .put(new DataStream("data-stream2", createTimestampField("@timestamp"), List.of(idx2.getIndex())))
             .build();
 
         XContentBuilder builder = JsonXContent.contentBuilder();
diff --git a/server/src/test/java/org/opensearch/cluster/metadata/WildcardExpressionResolverTests.java b/server/src/test/java/org/opensearch/cluster/metadata/WildcardExpressionResolverTests.java
index e4027234ac0b4..03807fb5f8c4d 100644
--- a/server/src/test/java/org/opensearch/cluster/metadata/WildcardExpressionResolverTests.java
+++ b/server/src/test/java/org/opensearch/cluster/metadata/WildcardExpressionResolverTests.java
@@ -302,7 +302,7 @@ public void testResolveDataStreams() {
                 new DataStream(
                     dataStreamName,
                     createTimestampField("@timestamp"),
-                    org.opensearch.common.collect.List.of(firstBackingIndexMetadata.getIndex(), secondBackingIndexMetadata.getIndex())
+                    List.of(firstBackingIndexMetadata.getIndex(), secondBackingIndexMetadata.getIndex())
                 )
             );
 
diff --git a/server/src/test/java/org/opensearch/cluster/routing/FailAwareWeightedRoutingTests.java b/server/src/test/java/org/opensearch/cluster/routing/FailAwareWeightedRoutingTests.java
index c9c616dab0dbc..5c3a2454c4074 100644
--- a/server/src/test/java/org/opensearch/cluster/routing/FailAwareWeightedRoutingTests.java
+++ b/server/src/test/java/org/opensearch/cluster/routing/FailAwareWeightedRoutingTests.java
@@ -31,6 +31,7 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.atomic.AtomicInteger;
 
 import static java.util.Collections.singletonMap;
 import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_CREATION_DATE;
@@ -88,7 +89,7 @@ private ClusterState setUpCluster() {
     public void testFindNextWithoutFailOpen() throws IOException {
 
         ClusterState clusterState = setUpCluster();
-
+        AtomicInteger shardSkipped = new AtomicInteger();
         // set up index
         IndexMetadata indexMetadata = IndexMetadata.builder("test")
             .settings(
@@ -137,8 +138,9 @@ public void testFindNextWithoutFailOpen() throws IOException {
 
         // fail open is not executed since fail open conditions don't met
         SearchShardTarget next = FailAwareWeightedRouting.getInstance()
-            .findNext(searchShardIterator, clusterState, new OpenSearchRejectedExecutionException());
+            .findNext(searchShardIterator, clusterState, new OpenSearchRejectedExecutionException(), () -> shardSkipped.incrementAndGet());
         assertNull(next);
+        assertEquals(1, shardSkipped.get());
     }
 
     public void testFindNextWithFailOpenDueTo5xx() throws IOException {
@@ -198,7 +200,7 @@ public void testFindNextWithFailOpenDueTo5xx() throws IOException {
         DiscoveryNode node = clusterState.nodes().get("node_zone_b");
         // fail open is executed and shard present in node with weighted routing weight zero is returned
         SearchShardTarget next = FailAwareWeightedRouting.getInstance()
-            .findNext(searchShardIterator, clusterState, new NodeNotConnectedException(node, "Node is not " + "connected"));
+            .findNext(searchShardIterator, clusterState, new NodeNotConnectedException(node, "Node is not " + "connected"), () -> {});
         assertNotNull(next);
         assertEquals("node_zone_c", next.getNodeId());
     }
@@ -206,7 +208,7 @@ public void testFindNextWithFailOpenDueTo5xx() throws IOException {
     public void testFindNextWithFailOpenDueToUnassignedShard() throws IOException {
 
         ClusterState clusterState = setUpCluster();
-
+        AtomicInteger shardsSkipped = new AtomicInteger();
         IndexMetadata indexMetadata = IndexMetadata.builder("test")
             .settings(
                 Settings.builder()
@@ -259,8 +261,9 @@ public void testFindNextWithFailOpenDueToUnassignedShard() throws IOException {
         // since there is an unassigned shard in the cluster, fail open is executed and shard present in node with
         // weighted routing weight zero is returned
         SearchShardTarget next = FailAwareWeightedRouting.getInstance()
-            .findNext(searchShardIterator, clusterState, new OpenSearchRejectedExecutionException());
+            .findNext(searchShardIterator, clusterState, new OpenSearchRejectedExecutionException(), () -> shardsSkipped.incrementAndGet());
         assertNotNull(next);
         assertEquals("node_zone_c", next.getNodeId());
+        assertEquals(1, shardsSkipped.incrementAndGet());
     }
 }
diff --git a/server/src/test/java/org/opensearch/cluster/routing/WeightedRoutingServiceTests.java b/server/src/test/java/org/opensearch/cluster/routing/WeightedRoutingServiceTests.java
index 65fc1b902f9a4..81464fcd2610d 100644
--- a/server/src/test/java/org/opensearch/cluster/routing/WeightedRoutingServiceTests.java
+++ b/server/src/test/java/org/opensearch/cluster/routing/WeightedRoutingServiceTests.java
@@ -43,6 +43,7 @@
 
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.CountDownLatch;
@@ -130,7 +131,7 @@ private ClusterState addClusterManagerNodes(ClusterState clusterState) {
 
     private ClusterState addDataNodeForAZone(ClusterState clusterState, String zone, String... nodeIds) {
         DiscoveryNodes.Builder nodeBuilder = DiscoveryNodes.builder(clusterState.nodes());
-        org.opensearch.common.collect.List.of(nodeIds)
+        List.of(nodeIds)
             .forEach(
                 nodeId -> nodeBuilder.add(
                     new DiscoveryNode(
@@ -149,7 +150,7 @@ private ClusterState addDataNodeForAZone(ClusterState clusterState, String zone,
     private ClusterState addClusterManagerNodeForAZone(ClusterState clusterState, String zone, String... nodeIds) {
 
         DiscoveryNodes.Builder nodeBuilder = DiscoveryNodes.builder(clusterState.nodes());
-        org.opensearch.common.collect.List.of(nodeIds)
+        List.of(nodeIds)
             .forEach(
                 nodeId -> nodeBuilder.add(
                     new DiscoveryNode(
diff --git a/server/src/test/java/org/opensearch/cluster/routing/allocation/AllocationConstraintsTests.java b/server/src/test/java/org/opensearch/cluster/routing/allocation/AllocationConstraintsTests.java
index ae10a92a5104e..937d0dd34226f 100644
--- a/server/src/test/java/org/opensearch/cluster/routing/allocation/AllocationConstraintsTests.java
+++ b/server/src/test/java/org/opensearch/cluster/routing/allocation/AllocationConstraintsTests.java
@@ -18,6 +18,10 @@
 import static org.mockito.Mockito.anyString;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.CLUSTER_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID;
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.CONSTRAINT_WEIGHT;
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.INDEX_SHARD_PER_NODE_BREACH_CONSTRAINT_ID;
+import static org.opensearch.cluster.routing.allocation.ConstraintTypes.INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID;
 
 public class AllocationConstraintsTests extends OpenSearchAllocationTestCase {
 
@@ -33,13 +37,18 @@ public void testSettings() {
         settings.put(BalancedShardsAllocator.INDEX_BALANCE_FACTOR_SETTING.getKey(), indexBalanceFactor);
         settings.put(BalancedShardsAllocator.SHARD_BALANCE_FACTOR_SETTING.getKey(), shardBalance);
         settings.put(BalancedShardsAllocator.THRESHOLD_SETTING.getKey(), threshold);
+        settings.put(BalancedShardsAllocator.PREFER_PRIMARY_SHARD_BALANCE.getKey(), true);
 
         service.applySettings(settings.build());
 
         assertEquals(indexBalanceFactor, allocator.getIndexBalance(), 0.01);
         assertEquals(shardBalance, allocator.getShardBalance(), 0.01);
         assertEquals(threshold, allocator.getThreshold(), 0.01);
+        assertEquals(true, allocator.getPreferPrimaryBalance());
 
+        settings.put(BalancedShardsAllocator.PREFER_PRIMARY_SHARD_BALANCE.getKey(), false);
+        service.applySettings(settings.build());
+        assertEquals(false, allocator.getPreferPrimaryBalance());
     }
 
     /**
@@ -50,6 +59,7 @@ public void testIndexShardsPerNodeConstraint() {
         ShardsBalancer balancer = mock(LocalShardsBalancer.class);
         BalancedShardsAllocator.ModelNode node = mock(BalancedShardsAllocator.ModelNode.class);
         AllocationConstraints constraints = new AllocationConstraints();
+        constraints.updateAllocationConstraint(INDEX_SHARD_PER_NODE_BREACH_CONSTRAINT_ID, true);
 
         int shardCount = randomIntBetween(1, 500);
         float avgShardsPerNode = 1.0f + (random().nextFloat()) * 999.0f;
@@ -58,9 +68,142 @@ public void testIndexShardsPerNodeConstraint() {
         when(node.numShards(anyString())).thenReturn(shardCount);
         when(node.getNodeId()).thenReturn("test-node");
 
-        long expectedWeight = (shardCount >= avgShardsPerNode) ? constraints.CONSTRAINT_WEIGHT : 0;
+        long expectedWeight = (shardCount >= avgShardsPerNode) ? CONSTRAINT_WEIGHT : 0;
         assertEquals(expectedWeight, constraints.weight(balancer, node, "index"));
 
     }
 
+    /**
+     * Test constraint evaluation logic when with different values of ConstraintMode
+     * for IndexShardPerNode constraint satisfied and breached.
+     */
+    public void testPerIndexPrimaryShardsConstraint() {
+        ShardsBalancer balancer = mock(LocalShardsBalancer.class);
+        BalancedShardsAllocator.ModelNode node = mock(BalancedShardsAllocator.ModelNode.class);
+        AllocationConstraints constraints = new AllocationConstraints();
+        constraints.updateAllocationConstraint(INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, true);
+
+        final String indexName = "test-index";
+        int perIndexPrimaryShardCount = 1;
+        float avgPerIndexPrimaryShardsPerNode = 2f;
+
+        when(balancer.avgPrimaryShardsPerNode(anyString())).thenReturn(avgPerIndexPrimaryShardsPerNode);
+        when(node.numPrimaryShards(anyString())).thenReturn(perIndexPrimaryShardCount);
+        when(node.getNodeId()).thenReturn("test-node");
+
+        assertEquals(0, constraints.weight(balancer, node, indexName));
+
+        perIndexPrimaryShardCount = 3;
+        when(node.numPrimaryShards(anyString())).thenReturn(perIndexPrimaryShardCount);
+        assertEquals(CONSTRAINT_WEIGHT, constraints.weight(balancer, node, indexName));
+
+        constraints.updateAllocationConstraint(INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, false);
+        assertEquals(0, constraints.weight(balancer, node, indexName));
+    }
+
+    /**
+     * Test constraint evaluation logic when per index primary shard count constraint is breached.
+     */
+    public void testGlobalPrimaryShardsConstraint() {
+        ShardsBalancer balancer = mock(LocalShardsBalancer.class);
+        BalancedShardsAllocator.ModelNode node = mock(BalancedShardsAllocator.ModelNode.class);
+        AllocationConstraints constraints = new AllocationConstraints();
+        constraints.updateAllocationConstraint(CLUSTER_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, true);
+
+        final String indexName = "test-index";
+        int primaryShardCount = 1;
+        float avgPrimaryShardsPerNode = 2f;
+
+        when(balancer.avgPrimaryShardsPerNode()).thenReturn(avgPrimaryShardsPerNode);
+        when(node.numPrimaryShards()).thenReturn(primaryShardCount);
+        when(node.getNodeId()).thenReturn("test-node");
+
+        assertEquals(0, constraints.weight(balancer, node, indexName));
+
+        primaryShardCount = 3;
+        when(node.numPrimaryShards()).thenReturn(primaryShardCount);
+        assertEquals(CONSTRAINT_WEIGHT, constraints.weight(balancer, node, indexName));
+
+        constraints.updateAllocationConstraint(CLUSTER_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, false);
+        assertEquals(0, constraints.weight(balancer, node, indexName));
+    }
+
+    /**
+     * Test constraint evaluation logic when both per index and global primary shard count constraint is breached.
+     */
+    public void testPrimaryShardsConstraints() {
+        ShardsBalancer balancer = mock(LocalShardsBalancer.class);
+        BalancedShardsAllocator.ModelNode node = mock(BalancedShardsAllocator.ModelNode.class);
+        AllocationConstraints constraints = new AllocationConstraints();
+        constraints.updateAllocationConstraint(CLUSTER_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, true);
+        constraints.updateAllocationConstraint(INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, true);
+
+        final String indexName = "test-index";
+        int perIndexPrimaryShardCount = 1;
+        float avgPerIndexPrimaryShardCount = 2;
+        int primaryShardCount = 2;
+        float avgPrimaryShardsPerNode = 4;
+
+        when(balancer.avgPrimaryShardsPerNode(indexName)).thenReturn(avgPerIndexPrimaryShardCount);
+        when(node.numPrimaryShards(indexName)).thenReturn(perIndexPrimaryShardCount);
+        when(balancer.avgPrimaryShardsPerNode()).thenReturn(avgPrimaryShardsPerNode);
+        when(node.numPrimaryShards()).thenReturn(primaryShardCount);
+        when(node.getNodeId()).thenReturn("test-node");
+
+        assertEquals(0, constraints.weight(balancer, node, indexName));
+
+        // breaching global primary shard count but not per index primary shard count
+        primaryShardCount = 5;
+        when(node.numPrimaryShards()).thenReturn(primaryShardCount);
+        assertEquals(CONSTRAINT_WEIGHT, constraints.weight(balancer, node, indexName));
+
+        // when per index primary shard count constraint is also breached
+        perIndexPrimaryShardCount = 3;
+        when(node.numPrimaryShards(indexName)).thenReturn(perIndexPrimaryShardCount);
+        assertEquals(2 * CONSTRAINT_WEIGHT, constraints.weight(balancer, node, indexName));
+
+        // disable both constraints
+        constraints.updateAllocationConstraint(INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, false);
+        constraints.updateAllocationConstraint(CLUSTER_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, false);
+        assertEquals(0, constraints.weight(balancer, node, indexName));
+    }
+
+    /**
+     * Test constraint evaluation logic when with different values of ConstraintMode
+     * for IndexShardPerNode constraint satisfied and breached.
+     */
+    public void testAllConstraints() {
+        ShardsBalancer balancer = mock(LocalShardsBalancer.class);
+        BalancedShardsAllocator.ModelNode node = mock(BalancedShardsAllocator.ModelNode.class);
+        AllocationConstraints constraints = new AllocationConstraints();
+        constraints.updateAllocationConstraint(INDEX_SHARD_PER_NODE_BREACH_CONSTRAINT_ID, true);
+        constraints.updateAllocationConstraint(INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, true);
+        constraints.updateAllocationConstraint(CLUSTER_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, true);
+
+        final String indexName = "test-index";
+        int shardCount = randomIntBetween(1, 500);
+        float avgPerIndexShardsPerNode = 1.0f + (random().nextFloat()) * 999.0f;
+
+        int perIndexPrimaryShardCount = randomIntBetween(1, shardCount);
+        float avgPerIndexPrimaryShardsPerNode = (random().nextFloat()) * avgPerIndexShardsPerNode;
+
+        float avgPrimaryShardsPerNode = 1.0f + (random().nextFloat()) * 999.0f;
+        int primaryShardsPerNode = randomIntBetween(1, shardCount);
+
+        when(balancer.avgPrimaryShardsPerNode(indexName)).thenReturn(avgPerIndexPrimaryShardsPerNode);
+        when(node.numPrimaryShards(indexName)).thenReturn(perIndexPrimaryShardCount);
+
+        when(balancer.avgPrimaryShardsPerNode()).thenReturn(avgPrimaryShardsPerNode);
+        when(node.numPrimaryShards()).thenReturn(primaryShardsPerNode);
+
+        when(balancer.avgShardsPerNode(indexName)).thenReturn(avgPerIndexShardsPerNode);
+        when(node.numShards(indexName)).thenReturn(shardCount);
+        when(node.getNodeId()).thenReturn("test-node");
+
+        long expectedWeight = (shardCount >= avgPerIndexShardsPerNode) ? CONSTRAINT_WEIGHT : 0;
+        expectedWeight += perIndexPrimaryShardCount > avgPerIndexPrimaryShardsPerNode ? CONSTRAINT_WEIGHT : 0;
+        expectedWeight += primaryShardsPerNode >= avgPrimaryShardsPerNode ? CONSTRAINT_WEIGHT : 0;
+        assertEquals(expectedWeight, constraints.weight(balancer, node, indexName));
+    }
+
 }
diff --git a/server/src/test/java/org/opensearch/cluster/routing/allocation/BalanceConfigurationTests.java b/server/src/test/java/org/opensearch/cluster/routing/allocation/BalanceConfigurationTests.java
index 1ba69694eaec1..f5a418bc6a100 100644
--- a/server/src/test/java/org/opensearch/cluster/routing/allocation/BalanceConfigurationTests.java
+++ b/server/src/test/java/org/opensearch/cluster/routing/allocation/BalanceConfigurationTests.java
@@ -33,10 +33,12 @@
 package org.opensearch.cluster.routing.allocation;
 
 import com.carrotsearch.hppc.cursors.ObjectCursor;
+import com.carrotsearch.hppc.cursors.ObjectObjectCursor;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.apache.lucene.util.ArrayUtil;
 import org.opensearch.Version;
+import org.opensearch.cluster.ClusterName;
 import org.opensearch.cluster.ClusterState;
 import org.opensearch.cluster.OpenSearchAllocationTestCase;
 import org.opensearch.cluster.EmptyClusterInfoService;
@@ -44,22 +46,37 @@
 import org.opensearch.cluster.metadata.Metadata;
 import org.opensearch.cluster.node.DiscoveryNode;
 import org.opensearch.cluster.node.DiscoveryNodes;
+import org.opensearch.cluster.routing.IndexRoutingTable;
+import org.opensearch.cluster.routing.IndexShardRoutingTable;
+import org.opensearch.cluster.routing.RecoverySource;
 import org.opensearch.cluster.routing.RoutingNode;
 import org.opensearch.cluster.routing.RoutingNodes;
 import org.opensearch.cluster.routing.RoutingTable;
 import org.opensearch.cluster.routing.ShardRouting;
 import org.opensearch.cluster.routing.ShardRoutingState;
+import org.opensearch.cluster.routing.TestShardRouting;
+import org.opensearch.cluster.routing.UnassignedInfo;
 import org.opensearch.cluster.routing.allocation.allocator.BalancedShardsAllocator;
 import org.opensearch.cluster.routing.allocation.allocator.ShardsAllocator;
 import org.opensearch.cluster.routing.allocation.decider.ClusterRebalanceAllocationDecider;
 import org.opensearch.common.settings.ClusterSettings;
 import org.opensearch.common.settings.Settings;
+import org.opensearch.index.shard.ShardId;
 import org.opensearch.snapshots.EmptySnapshotsInfoService;
 import org.opensearch.test.gateway.TestGatewayAllocator;
 import org.hamcrest.Matchers;
 
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
 
+import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_CREATION_DATE;
+import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_NUMBER_OF_REPLICAS;
+import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_NUMBER_OF_SHARDS;
+import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_VERSION_CREATED;
 import static org.opensearch.cluster.routing.ShardRoutingState.STARTED;
 import static org.opensearch.cluster.routing.ShardRoutingState.UNASSIGNED;
 
@@ -75,7 +92,7 @@ public class BalanceConfigurationTests extends OpenSearchAllocationTestCase {
     public void testIndexBalance() {
         /* Tests balance over indices only */
         final float indexBalance = 1.0f;
-        final float replicaBalance = 0.0f;
+        final float shardBalance = 0.0f;
         final float balanceThreshold = 1.0f;
 
         Settings.Builder settings = Settings.builder();
@@ -84,7 +101,7 @@ public void testIndexBalance() {
             ClusterRebalanceAllocationDecider.ClusterRebalanceType.ALWAYS.toString()
         );
         settings.put(BalancedShardsAllocator.INDEX_BALANCE_FACTOR_SETTING.getKey(), indexBalance);
-        settings.put(BalancedShardsAllocator.SHARD_BALANCE_FACTOR_SETTING.getKey(), replicaBalance);
+        settings.put(BalancedShardsAllocator.SHARD_BALANCE_FACTOR_SETTING.getKey(), shardBalance);
         settings.put(BalancedShardsAllocator.THRESHOLD_SETTING.getKey(), balanceThreshold);
 
         AllocationService strategy = createAllocationService(settings.build(), new TestGatewayAllocator());
@@ -123,10 +140,428 @@ public void testIndexBalance() {
         );
     }
 
-    public void testReplicaBalance() {
+    private Settings.Builder getSettingsBuilderForPrimaryBalance() {
+        return getSettingsBuilderForPrimaryBalance(true);
+    }
+
+    private Settings.Builder getSettingsBuilderForPrimaryBalance(boolean preferPrimaryBalance) {
+        final float indexBalance = 0.55f;
+        final float shardBalance = 0.45f;
+        final float balanceThreshold = 1.0f;
+
+        Settings.Builder settings = Settings.builder();
+        settings.put(
+            ClusterRebalanceAllocationDecider.CLUSTER_ROUTING_ALLOCATION_ALLOW_REBALANCE_SETTING.getKey(),
+            ClusterRebalanceAllocationDecider.ClusterRebalanceType.ALWAYS.toString()
+        );
+        settings.put(BalancedShardsAllocator.INDEX_BALANCE_FACTOR_SETTING.getKey(), indexBalance);
+        settings.put(BalancedShardsAllocator.PREFER_PRIMARY_SHARD_BALANCE.getKey(), preferPrimaryBalance);
+        settings.put(BalancedShardsAllocator.SHARD_BALANCE_FACTOR_SETTING.getKey(), shardBalance);
+        settings.put(BalancedShardsAllocator.THRESHOLD_SETTING.getKey(), balanceThreshold);
+        return settings;
+    }
+
+    private IndexMetadata getIndexMetadata(String indexName, int shardCount, int replicaCount) {
+        return IndexMetadata.builder(indexName)
+            .settings(
+                Settings.builder()
+                    .put(SETTING_VERSION_CREATED, Version.CURRENT)
+                    .put(SETTING_NUMBER_OF_SHARDS, shardCount)
+                    .put(SETTING_NUMBER_OF_REPLICAS, replicaCount)
+                    .put(SETTING_CREATION_DATE, System.currentTimeMillis())
+            )
+            .build();
+    }
+
+    /**
+     * This test verifies that with only primary shard balance, the primary shard distribution per index is balanced.
+     */
+    public void testPrimaryBalance() {
+        AllocationService strategy = createAllocationService(getSettingsBuilderForPrimaryBalance().build(), new TestGatewayAllocator());
+
+        ClusterState clusterState = initCluster(strategy);
+        verifyPerIndexPrimaryBalance(clusterState);
+
+        clusterState = addNode(clusterState, strategy);
+        verifyPerIndexPrimaryBalance(clusterState);
+
+        clusterState = removeNodes(clusterState, strategy);
+        verifyPerIndexPrimaryBalance(clusterState);
+    }
+
+    /**
+     * This test verifies primary shard balance is not attained without PREFER_PRIMARY_SHARD_BALANCE setting.
+     */
+    public void testPrimaryBalanceWithoutPreferPrimaryBalanceSetting() {
+        final int numberOfNodes = 5;
+        final int numberOfIndices = 5;
+        final int numberOfShards = 25;
+        final int numberOfReplicas = 1;
+
+        final int numberOfRuns = 5;
+        int balanceFailed = 0;
+
+        AllocationService strategy = createAllocationService(
+            getSettingsBuilderForPrimaryBalance(false).build(),
+            new TestGatewayAllocator()
+        );
+        for (int i = 0; i < numberOfRuns; i++) {
+            ClusterState clusterState = initCluster(strategy, numberOfIndices, numberOfNodes, numberOfShards, numberOfReplicas);
+            clusterState = removeOneNode(clusterState, strategy);
+            logger.info(ShardAllocations.printShardDistribution(clusterState));
+            try {
+                verifyPerIndexPrimaryBalance(clusterState);
+            } catch (AssertionError e) {
+                balanceFailed++;
+                logger.info("Expected assertion failure");
+            }
+        }
+        assertTrue(balanceFailed >= 4);
+    }
+
+    /**
+     * This test verifies primary shard balance is attained with PREFER_PRIMARY_SHARD_BALANCE setting.
+     */
+    public void testPrimaryBalanceWithPreferPrimaryBalanceSetting() {
+        final int numberOfNodes = 5;
+        final int numberOfIndices = 5;
+        final int numberOfShards = 25;
+        final int numberOfReplicas = 1;
+        final int numberOfRuns = 5;
+        int balanceFailed = 0;
+
+        AllocationService strategy = createAllocationService(getSettingsBuilderForPrimaryBalance().build(), new TestGatewayAllocator());
+        for (int i = 0; i < numberOfRuns; i++) {
+            ClusterState clusterState = initCluster(strategy, numberOfIndices, numberOfNodes, numberOfShards, numberOfReplicas);
+            clusterState = removeOneNode(clusterState, strategy);
+            logger.info(ShardAllocations.printShardDistribution(clusterState));
+            try {
+                verifyPerIndexPrimaryBalance(clusterState);
+            } catch (AssertionError e) {
+                balanceFailed++;
+                logger.info("Unexpected assertion failure");
+            }
+        }
+        assertTrue(balanceFailed <= 1);
+    }
+
+    /**
+     * This test verifies the allocation logic when nodes breach multiple constraints and ensure node breaching min
+     * constraints chosen for allocation.
+     *
+     * This test mimics a cluster state containing four nodes, where one node breaches two constraints while one breaches
+     * only one. In order to have nodes breach constraints, test excludes two nodes (node2, node3) from allocation so
+     * that other two nodes (node0, node1) have all shards assignments resulting in constraints breach. Test asserts that
+     * the new primary shard assignment lands on the node breaching one constraint(node1), while replica land on the other
+     * (node0). Final shard allocation state.
+     *
+     routing_nodes:
+     -----node_id[node2][V]
+     -----node_id[node3][V]
+     -----node_id[node0][V]
+     --------[test][1], node[node0], [P], s[STARTED], a[id=7B4dVsrjSoC6imBHO60mrQ]
+     --------[test][0], node[node0], [P], s[STARTED], a[id=0HySaPcyRhiKrH6QLA3evw]
+     --------[test][2], node[node0], [R], s[STARTED], a[id=pB3iuLKZSC--2yNS0trbgA]
+     -----node_id[node1][V]
+     --------[test][2], node[node1], [P], s[STARTED], a[id=QWN_T6xpQiWGSD8GJnX-bQ]
+     --------[test][1], node[node1], [R], s[STARTED], a[id=ChWdQiOdSdKrTPxwceIu1w]
+     --------[test][0], node[node1], [R], s[STARTED], a[id=5Adc5JteQ8-lY2xfsHUg-Q]
+     *
+     */
+    public void testPrimaryBalanceWithContrainstBreaching() {
+        // Mark node2, node 3 excluded (FilterAllocationDecider) so that all allocations land on node 0, node 1
+        Settings.Builder settingsBuilder = getSettingsBuilderForPrimaryBalance();
+        settingsBuilder.put("cluster.routing.allocation.exclude._id", "node2,node3");
+
+        AllocationService strategy = createAllocationService(settingsBuilder.build(), new TestGatewayAllocator());
+        DiscoveryNodes.Builder discoBuilder = DiscoveryNodes.builder();
+        List<String> nodesList = new ArrayList<>();
+        for (int i = 0; i < 4; i++) {
+            final DiscoveryNode node = newNode("node" + i);
+            discoBuilder = discoBuilder.add(node);
+            nodesList.add(node.getId());
+        }
+        discoBuilder.localNodeId(newNode("node_0").getId());
+        discoBuilder.clusterManagerNodeId(newNode("node_0").getId());
+
+        Metadata.Builder metadata = Metadata.builder();
+        metadata.persistentSettings(settingsBuilder.build());
+        RoutingTable.Builder routingTable = RoutingTable.builder();
+        // build index metadata
+        IndexMetadata indexMetadata = getIndexMetadata("test", 3, 1);
+        // Build index routing table
+        IndexRoutingTable.Builder indexRoutingTable = IndexRoutingTable.builder(indexMetadata.getIndex());
+        ShardId shardId_0 = new ShardId(indexMetadata.getIndex(), 0);
+        ShardId shardId_1 = new ShardId(indexMetadata.getIndex(), 1);
+        ShardId shardId_2 = new ShardId(indexMetadata.getIndex(), 2);
+        UnassignedInfo unassignedInfo = new UnassignedInfo(UnassignedInfo.Reason.INDEX_CREATED, null);
+        IndexShardRoutingTable.Builder indexShardRoutingBuilder_0 = new IndexShardRoutingTable.Builder(shardId_0);
+        IndexShardRoutingTable.Builder indexShardRoutingBuilder_1 = new IndexShardRoutingTable.Builder(shardId_1);
+        IndexShardRoutingTable.Builder indexShardRoutingBuilder_2 = new IndexShardRoutingTable.Builder(shardId_2);
+        indexShardRoutingBuilder_0.addShard(TestShardRouting.newShardRouting(shardId_0, nodesList.get(0), true, ShardRoutingState.STARTED));
+        indexShardRoutingBuilder_1.addShard(TestShardRouting.newShardRouting(shardId_1, nodesList.get(0), true, ShardRoutingState.STARTED));
+        indexShardRoutingBuilder_0.addShard(
+            TestShardRouting.newShardRouting(shardId_0, nodesList.get(1), false, ShardRoutingState.STARTED)
+        );
+        indexShardRoutingBuilder_1.addShard(
+            TestShardRouting.newShardRouting(shardId_1, nodesList.get(1), false, ShardRoutingState.STARTED)
+        );
+        indexShardRoutingBuilder_2.addShard(
+            TestShardRouting.newShardRouting(
+                shardId_2,
+                null,
+                null,
+                true,
+                UNASSIGNED,
+                RecoverySource.EmptyStoreRecoverySource.INSTANCE,
+                unassignedInfo
+            )
+        );
+        indexShardRoutingBuilder_2.addShard(
+            TestShardRouting.newShardRouting(
+                shardId_2,
+                null,
+                null,
+                false,
+                UNASSIGNED,
+                RecoverySource.PeerRecoverySource.INSTANCE,
+                unassignedInfo
+            )
+        );
+
+        IndexShardRoutingTable indexShardRoutingTable_0 = indexShardRoutingBuilder_0.build();
+        IndexShardRoutingTable indexShardRoutingTable_1 = indexShardRoutingBuilder_1.build();
+
+        indexRoutingTable.addIndexShard(indexShardRoutingBuilder_0.build());
+        indexRoutingTable.addIndexShard(indexShardRoutingBuilder_1.build());
+        indexRoutingTable.addIndexShard(indexShardRoutingBuilder_2.build());
+        routingTable.add(indexRoutingTable);
+
+        IndexMetadata.Builder indexMetaDataBuilder = IndexMetadata.builder(indexMetadata);
+        indexMetaDataBuilder.putInSyncAllocationIds(0, indexShardRoutingTable_0.getAllAllocationIds());
+        indexMetaDataBuilder.putInSyncAllocationIds(1, indexShardRoutingTable_1.getAllAllocationIds());
+        metadata.put(indexMetaDataBuilder.build(), false);
+
+        ClusterState.Builder stateBuilder = ClusterState.builder(new ClusterName("test"));
+        stateBuilder.nodes(discoBuilder);
+        stateBuilder.metadata(metadata.generateClusterUuidIfNeeded().build());
+        stateBuilder.routingTable(routingTable.build());
+        ClusterState clusterState = stateBuilder.build();
+        clusterState = strategy.reroute(clusterState, "reroute");
+        clusterState = applyAllocationUntilNoChange(clusterState, strategy);
+
+        logger.info(ShardAllocations.printShardDistribution(clusterState));
+        ShardRouting primaryShard = clusterState.routingTable().shardRoutingTable(shardId_2).primaryShard();
+        List<ShardRouting> replicaShards = clusterState.routingTable().shardRoutingTable(shardId_2).replicaShards();
+
+        assertTrue(primaryShard.started());
+        assertEquals("node1", primaryShard.currentNodeId());
+
+        assertEquals(1, replicaShards.size());
+        assertTrue(replicaShards.get(0).started());
+        assertEquals("node0", replicaShards.get(0).currentNodeId());
+    }
+
+    /**
+     * This test verifies global balance by creating indices iteratively and verify primary shards do not pile up on one
+     * node.
+     * @throws Exception
+     */
+    public void testGlobalPrimaryBalance() throws Exception {
+        AllocationService strategy = createAllocationService(getSettingsBuilderForPrimaryBalance().build(), new TestGatewayAllocator());
+        ClusterState clusterState = ClusterState.builder(org.opensearch.cluster.ClusterName.CLUSTER_NAME_SETTING.getDefault(Settings.EMPTY))
+            .build();
+        clusterState = addNode(clusterState, strategy);
+        clusterState = addNode(clusterState, strategy);
+
+        clusterState = addIndex(clusterState, strategy, "test-index1", 1, 1);
+        clusterState = addIndex(clusterState, strategy, "test-index2", 1, 1);
+        clusterState = addIndex(clusterState, strategy, "test-index3", 1, 1);
+
+        logger.info(ShardAllocations.printShardDistribution(clusterState));
+        verifyPrimaryBalance(clusterState);
+    }
+
+    /**
+     * This test mimics a cluster state which can not be rebalanced due to
+     * {@link org.opensearch.cluster.routing.allocation.decider.SameShardAllocationDecider}
+     * allocation decider which prevents shard relocation, leaving cluster unbalanced on primaries.
+     *
+     * There are two nodes (N1, N2) where all primaries land on N1 while replicas on N2.
+     * N1        N2
+     * ------  --------
+     * P1        R1
+     * P2        R2
+     *
+     * -----node_id[node_0][V]
+     * --------[test][1], node[node_0], [P], s[STARTED], a[id=xqfZSToVSQaff2xvuxh_yA]
+     * --------[test][0], node[node_0], [P], s[STARTED], a[id=VGjOeBGdSmu3pJR6T7v29A]
+     * -----node_id[node_1][V]
+     * --------[test][1], node[node_1], [R], s[STARTED], a[id=zZI0R8FBQkWMNndEZt9d8w]
+     * --------[test][0], node[node_1], [R], s[STARTED], a[id=8IpwEMQ2QEuj5rQOxBagSA]
+     */
+    public void testPrimaryBalance_NotSolved_1() {
+        AllocationService strategy = createAllocationService(getSettingsBuilderForPrimaryBalance().build(), new TestGatewayAllocator());
+
+        DiscoveryNodes.Builder discoBuilder = DiscoveryNodes.builder();
+        Set<String> nodes = new HashSet<>();
+        for (int i = 0; i < 2; i++) {
+            final DiscoveryNode node = newNode("node_" + i);
+            discoBuilder = discoBuilder.add(node);
+            nodes.add(node.getId());
+        }
+        discoBuilder.localNodeId(newNode("node_0").getId());
+        discoBuilder.clusterManagerNodeId(newNode("node_0").getId());
+        Metadata.Builder metadata = Metadata.builder();
+        RoutingTable.Builder routingTable = RoutingTable.builder();
+        List<String> nodesList = new ArrayList<>(nodes);
+        // build index metadata
+        IndexMetadata indexMetadata = getIndexMetadata("test", 2, 1);
+        IndexRoutingTable.Builder indexRoutingTable = IndexRoutingTable.builder(indexMetadata.getIndex());
+        ShardId shardId_0 = new ShardId(indexMetadata.getIndex(), 0);
+        ShardId shardId_1 = new ShardId(indexMetadata.getIndex(), 1);
+        IndexShardRoutingTable.Builder indexShardRoutingBuilder_0 = new IndexShardRoutingTable.Builder(shardId_0);
+        IndexShardRoutingTable.Builder indexShardRoutingBuilder_1 = new IndexShardRoutingTable.Builder(shardId_1);
+        indexShardRoutingBuilder_0.addShard(TestShardRouting.newShardRouting(shardId_0, nodesList.get(0), true, ShardRoutingState.STARTED));
+        indexShardRoutingBuilder_1.addShard(TestShardRouting.newShardRouting(shardId_1, nodesList.get(0), true, ShardRoutingState.STARTED));
+        indexShardRoutingBuilder_0.addShard(
+            TestShardRouting.newShardRouting(shardId_0, nodesList.get(1), false, ShardRoutingState.STARTED)
+        );
+        indexShardRoutingBuilder_1.addShard(
+            TestShardRouting.newShardRouting(shardId_1, nodesList.get(1), false, ShardRoutingState.STARTED)
+        );
+        indexRoutingTable.addIndexShard(indexShardRoutingBuilder_0.build());
+        indexRoutingTable.addIndexShard(indexShardRoutingBuilder_1.build());
+        metadata.put(indexMetadata, false);
+        routingTable.add(indexRoutingTable);
+
+        ClusterState.Builder stateBuilder = ClusterState.builder(new ClusterName("test"));
+        stateBuilder.nodes(discoBuilder);
+        stateBuilder.metadata(metadata.generateClusterUuidIfNeeded().build());
+        stateBuilder.routingTable(routingTable.build());
+        ClusterState clusterState = stateBuilder.build();
+
+        clusterState = strategy.reroute(clusterState, "reroute");
+        boolean balanced = true;
+        logger.info(ShardAllocations.printShardDistribution(clusterState));
+        try {
+            verifyPerIndexPrimaryBalance(clusterState);
+        } catch (AssertionError e) {
+            balanced = false;
+        }
+        assertFalse(balanced);
+    }
+
+    /**
+     * This test mimics cluster state where re-balancing is not possible due to existing limitation of re-balancing
+     * logic which applies at index level i.e. balance shards single index across all nodes. This will be solved when
+     * primary shard count across indices, constraint is added.
+     *
+     * Please note, P1, P2 belongs to different index
+     *
+     * N1        N2
+     * ------  --------
+     * P1       R1
+     * P2       R2
+     *
+     * -----node_id[node_0][V]
+     * --------[test1][0], node[node_0], [P], s[STARTED], a[id=u7qtyy5AR42hgEa-JpeArg]
+     * --------[test0][0], node[node_0], [P], s[STARTED], a[id=BQrLSo6sQyGlcLdVvGgqLQ]
+     * -----node_id[node_1][V]
+     * --------[test1][0], node[node_1], [R], s[STARTED], a[id=TDqbfvAfSFK6lnv3aOU9bA]
+     * --------[test0][0], node[node_1], [R], s[STARTED], a[id=E85-jhiEQwuB43u5Wq1mAw]
+     *
+     */
+    public void testPrimaryBalance_NotSolved_2() {
+        AllocationService strategy = createAllocationService(getSettingsBuilderForPrimaryBalance().build(), new TestGatewayAllocator());
+
+        DiscoveryNodes.Builder discoBuilder = DiscoveryNodes.builder();
+        Set<String> nodes = new HashSet<>();
+        for (int i = 0; i < 2; i++) {
+            final DiscoveryNode node = newNode("node_" + i);
+            discoBuilder = discoBuilder.add(node);
+            nodes.add(node.getId());
+        }
+        discoBuilder.localNodeId(newNode("node_0").getId());
+        discoBuilder.clusterManagerNodeId(newNode("node_0").getId());
+        Metadata.Builder metadata = Metadata.builder();
+        RoutingTable.Builder routingTable = RoutingTable.builder();
+        List<String> nodesList = new ArrayList<>(nodes);
+        // build index metadata
+        IndexMetadata indexMetadata_0 = getIndexMetadata("test0", 1, 1);
+        IndexMetadata indexMetadata_1 = getIndexMetadata("test1", 1, 1);
+        IndexRoutingTable.Builder indexRoutingTable_0 = IndexRoutingTable.builder(indexMetadata_0.getIndex());
+        IndexRoutingTable.Builder indexRoutingTable_1 = IndexRoutingTable.builder(indexMetadata_1.getIndex());
+        ShardId shardId_0 = new ShardId(indexMetadata_0.getIndex(), 0);
+        ShardId shardId_1 = new ShardId(indexMetadata_1.getIndex(), 0);
+        IndexShardRoutingTable.Builder indexShardRoutingBuilder_0 = new IndexShardRoutingTable.Builder(shardId_0);
+        IndexShardRoutingTable.Builder indexShardRoutingBuilder_1 = new IndexShardRoutingTable.Builder(shardId_1);
+        indexShardRoutingBuilder_0.addShard(TestShardRouting.newShardRouting(shardId_0, nodesList.get(0), true, ShardRoutingState.STARTED));
+        indexShardRoutingBuilder_1.addShard(TestShardRouting.newShardRouting(shardId_1, nodesList.get(0), true, ShardRoutingState.STARTED));
+        indexShardRoutingBuilder_0.addShard(
+            TestShardRouting.newShardRouting(shardId_0, nodesList.get(1), false, ShardRoutingState.STARTED)
+        );
+        indexShardRoutingBuilder_1.addShard(
+            TestShardRouting.newShardRouting(shardId_1, nodesList.get(1), false, ShardRoutingState.STARTED)
+        );
+        indexRoutingTable_0.addIndexShard(indexShardRoutingBuilder_0.build());
+        indexRoutingTable_1.addIndexShard(indexShardRoutingBuilder_1.build());
+        metadata.put(indexMetadata_0, false);
+        metadata.put(indexMetadata_1, false);
+        routingTable.add(indexRoutingTable_0);
+        routingTable.add(indexRoutingTable_1);
+        ClusterState.Builder stateBuilder = ClusterState.builder(new ClusterName("test"));
+        stateBuilder.nodes(discoBuilder);
+        stateBuilder.metadata(metadata.generateClusterUuidIfNeeded().build());
+        stateBuilder.routingTable(routingTable.build());
+        ClusterState clusterState = stateBuilder.build();
+
+        clusterState = strategy.reroute(clusterState, "reroute");
+        logger.info(ShardAllocations.printShardDistribution(clusterState));
+        // The cluster is balanced when considering indices individually not balanced when considering global state
+        verifyPerIndexPrimaryBalance(clusterState);
+    }
+
+    private void verifyPerIndexPrimaryBalance(ClusterState currentState) {
+        RoutingNodes nodes = currentState.getRoutingNodes();
+        for (ObjectObjectCursor<String, IndexRoutingTable> index : currentState.getRoutingTable().indicesRouting()) {
+            final int totalPrimaryShards = index.value.primaryShardsActive();
+            final int avgPrimaryShardsPerNode = (int) Math.ceil(totalPrimaryShards * 1f / currentState.getRoutingNodes().size());
+
+            for (RoutingNode node : nodes) {
+                final int primaryCount = node.shardsWithState(index.key, STARTED)
+                    .stream()
+                    .filter(ShardRouting::primary)
+                    .collect(Collectors.toList())
+                    .size();
+                assertTrue(primaryCount <= avgPrimaryShardsPerNode);
+            }
+        }
+    }
+
+    private void verifyPrimaryBalance(ClusterState clusterState) throws Exception {
+        assertBusy(() -> {
+            RoutingNodes nodes = clusterState.getRoutingNodes();
+            int totalPrimaryShards = 0;
+            for (ObjectObjectCursor<String, IndexRoutingTable> index : clusterState.getRoutingTable().indicesRouting()) {
+                totalPrimaryShards += index.value.primaryShardsActive();
+            }
+            final int avgPrimaryShardsPerNode = (int) Math.ceil(totalPrimaryShards * 1f / clusterState.getRoutingNodes().size());
+            for (RoutingNode node : nodes) {
+                final int primaryCount = node.shardsWithState(STARTED)
+                    .stream()
+                    .filter(ShardRouting::primary)
+                    .collect(Collectors.toList())
+                    .size();
+                assertTrue(primaryCount <= avgPrimaryShardsPerNode);
+            }
+        }, 60, TimeUnit.SECONDS);
+    }
+
+    public void testShardBalance() {
         /* Tests balance over replicas only */
         final float indexBalance = 0.0f;
-        final float replicaBalance = 1.0f;
+        final float shardBalance = 1.0f;
         final float balanceThreshold = 1.0f;
 
         Settings.Builder settings = Settings.builder();
@@ -135,13 +570,13 @@ public void testReplicaBalance() {
             ClusterRebalanceAllocationDecider.ClusterRebalanceType.ALWAYS.toString()
         );
         settings.put(BalancedShardsAllocator.INDEX_BALANCE_FACTOR_SETTING.getKey(), indexBalance);
-        settings.put(BalancedShardsAllocator.SHARD_BALANCE_FACTOR_SETTING.getKey(), replicaBalance);
+        settings.put(BalancedShardsAllocator.SHARD_BALANCE_FACTOR_SETTING.getKey(), shardBalance);
         settings.put(BalancedShardsAllocator.THRESHOLD_SETTING.getKey(), balanceThreshold);
 
         AllocationService strategy = createAllocationService(settings.build(), new TestGatewayAllocator());
 
         ClusterState clusterState = initCluster(strategy);
-        assertReplicaBalance(
+        assertShardBalance(
             clusterState.getRoutingNodes(),
             numberOfNodes,
             numberOfIndices,
@@ -151,7 +586,7 @@ public void testReplicaBalance() {
         );
 
         clusterState = addNode(clusterState, strategy);
-        assertReplicaBalance(
+        assertShardBalance(
             clusterState.getRoutingNodes(),
             numberOfNodes + 1,
             numberOfIndices,
@@ -161,7 +596,7 @@ public void testReplicaBalance() {
         );
 
         clusterState = removeNodes(clusterState, strategy);
-        assertReplicaBalance(
+        assertShardBalance(
             clusterState.getRoutingNodes(),
             numberOfNodes + 1 - (numberOfNodes + 1) / 2,
             numberOfIndices,
@@ -172,19 +607,54 @@ public void testReplicaBalance() {
     }
 
     private ClusterState initCluster(AllocationService strategy) {
+        return initCluster(strategy, numberOfIndices, numberOfNodes, numberOfShards, numberOfReplicas);
+    }
+
+    private ClusterState addIndex(
+        ClusterState clusterState,
+        AllocationService strategy,
+        String indexName,
+        int numberOfShards,
+        int numberOfReplicas
+    ) {
+        Metadata.Builder metadataBuilder = Metadata.builder(clusterState.getMetadata());
+        RoutingTable.Builder routingTableBuilder = RoutingTable.builder(clusterState.routingTable());
+
+        IndexMetadata.Builder index = IndexMetadata.builder(indexName)
+            .settings(settings(Version.CURRENT))
+            .numberOfShards(numberOfShards)
+            .numberOfReplicas(numberOfReplicas);
+
+        metadataBuilder = metadataBuilder.put(index);
+        routingTableBuilder.addAsNew(index.build());
+
+        clusterState = ClusterState.builder(clusterState)
+            .metadata(metadataBuilder.build())
+            .routingTable(routingTableBuilder.build())
+            .build();
+        clusterState = strategy.reroute(clusterState, "index-created");
+        return applyAllocationUntilNoChange(clusterState, strategy);
+    }
+
+    private ClusterState initCluster(
+        AllocationService strategy,
+        int numberOfIndices,
+        int numberOfNodes,
+        int numberOfShards,
+        int numberOfReplicas
+    ) {
         Metadata.Builder metadataBuilder = Metadata.builder();
         RoutingTable.Builder routingTableBuilder = RoutingTable.builder();
 
         for (int i = 0; i < numberOfIndices; i++) {
             IndexMetadata.Builder index = IndexMetadata.builder("test" + i)
-                .settings(settings(Version.CURRENT))
+                .settings(settings(Version.CURRENT).build())
                 .numberOfShards(numberOfShards)
                 .numberOfReplicas(numberOfReplicas);
             metadataBuilder = metadataBuilder.put(index);
         }
 
         Metadata metadata = metadataBuilder.build();
-
         for (ObjectCursor<IndexMetadata> cursor : metadata.indices().values()) {
             routingTableBuilder.addAsNew(cursor.value);
         }
@@ -202,21 +672,13 @@ private ClusterState initCluster(AllocationService strategy) {
             .routingTable(initialRoutingTable)
             .build();
         clusterState = strategy.reroute(clusterState, "reroute");
-
-        logger.info("restart all the primary shards, replicas will start initializing");
-        clusterState = startInitializingShardsAndReroute(strategy, clusterState);
-
-        logger.info("start the replica shards");
-        clusterState = startInitializingShardsAndReroute(strategy, clusterState);
-
-        logger.info("complete rebalancing");
-        return applyStartedShardsUntilNoChange(clusterState, strategy);
+        return applyAllocationUntilNoChange(clusterState, strategy);
     }
 
     private ClusterState addNode(ClusterState clusterState, AllocationService strategy) {
         logger.info("now, start 1 more node, check that rebalancing will happen because we set it to always");
         clusterState = ClusterState.builder(clusterState)
-            .nodes(DiscoveryNodes.builder(clusterState.nodes()).add(newNode("node" + numberOfNodes)))
+            .nodes(DiscoveryNodes.builder(clusterState.nodes()).add(newNode("node" + clusterState.getRoutingNodes().size())))
             .build();
 
         RoutingTable routingTable = strategy.reroute(clusterState, "reroute").routingTable();
@@ -226,7 +688,16 @@ private ClusterState addNode(ClusterState clusterState, AllocationService strate
         return applyStartedShardsUntilNoChange(clusterState, strategy);
     }
 
+    private ClusterState removeOneNode(ClusterState clusterState, AllocationService strategy) {
+        DiscoveryNodes.Builder nodes = DiscoveryNodes.builder(clusterState.nodes());
+        nodes.remove("node0");
+        clusterState = ClusterState.builder(clusterState).nodes(nodes.build()).build();
+        clusterState = strategy.disassociateDeadNodes(clusterState, randomBoolean(), "removed nodes");
+        return applyAllocationUntilNoChange(clusterState, strategy);
+    }
+
     private ClusterState removeNodes(ClusterState clusterState, AllocationService strategy) {
+        int numberOfNodes = clusterState.getRoutingNodes().size();
         logger.info("Removing half the nodes (" + (numberOfNodes + 1) / 2 + ")");
         DiscoveryNodes.Builder nodes = DiscoveryNodes.builder(clusterState.nodes());
 
@@ -240,7 +711,10 @@ private ClusterState removeNodes(ClusterState clusterState, AllocationService st
         if (removed) {
             clusterState = strategy.disassociateDeadNodes(clusterState, randomBoolean(), "removed nodes");
         }
+        return applyAllocationUntilNoChange(clusterState, strategy);
+    }
 
+    private ClusterState applyAllocationUntilNoChange(ClusterState clusterState, AllocationService strategy) {
         logger.info("start all the primary shards, replicas will start initializing");
         clusterState = startInitializingShardsAndReroute(strategy, clusterState);
 
@@ -254,7 +728,7 @@ private ClusterState removeNodes(ClusterState clusterState, AllocationService st
         return applyStartedShardsUntilNoChange(clusterState, strategy);
     }
 
-    private void assertReplicaBalance(
+    private void assertShardBalance(
         RoutingNodes nodes,
         int numberOfNodes,
         int numberOfIndices,
@@ -494,5 +968,4 @@ public ShardAllocationDecision decideShardAllocation(ShardRouting shard, Routing
             }
         }
     }
-
 }
diff --git a/server/src/test/java/org/opensearch/cluster/routing/allocation/DiskThresholdMonitorTests.java b/server/src/test/java/org/opensearch/cluster/routing/allocation/DiskThresholdMonitorTests.java
index 4c4b362ef7c56..e4f3c4eeeb903 100644
--- a/server/src/test/java/org/opensearch/cluster/routing/allocation/DiskThresholdMonitorTests.java
+++ b/server/src/test/java/org/opensearch/cluster/routing/allocation/DiskThresholdMonitorTests.java
@@ -61,6 +61,7 @@
 import java.util.HashSet;
 import java.util.Set;
 import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicLong;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.LongSupplier;
@@ -681,6 +682,56 @@ protected void setIndexCreateBlock(ActionListener<Void> listener, boolean indexC
         );
     }
 
+    public void testIndexCreateBlockWhenNoDataNodeHealthy() {
+        AllocationService allocation = createAllocationService(
+            Settings.builder().put("cluster.routing.allocation.node_concurrent_recoveries", 10).build()
+        );
+        Metadata metadata = Metadata.builder().build();
+        RoutingTable routingTable = RoutingTable.builder().build();
+        final ClusterState clusterState = applyStartedShardsUntilNoChange(
+            ClusterState.builder(ClusterName.CLUSTER_NAME_SETTING.getDefault(Settings.EMPTY))
+                .metadata(metadata)
+                .routingTable(routingTable)
+                .build(),
+            allocation
+        );
+        AtomicInteger countBlocksCalled = new AtomicInteger();
+        AtomicBoolean reroute = new AtomicBoolean(false);
+        AtomicReference<Set<String>> indices = new AtomicReference<>();
+        AtomicLong currentTime = new AtomicLong();
+        Settings settings = Settings.builder().build();
+        DiskThresholdMonitor monitor = new DiskThresholdMonitor(
+            settings,
+            () -> clusterState,
+            new ClusterSettings(settings, ClusterSettings.BUILT_IN_CLUSTER_SETTINGS),
+            null,
+            currentTime::get,
+            (reason, priority, listener) -> {
+                assertTrue(reroute.compareAndSet(false, true));
+                assertThat(priority, equalTo(Priority.HIGH));
+                listener.onResponse(null);
+            }
+        ) {
+
+            @Override
+            protected void updateIndicesReadOnly(Set<String> indicesToMarkReadOnly, ActionListener<Void> listener, boolean readOnly) {
+                assertTrue(indices.compareAndSet(null, indicesToMarkReadOnly));
+                assertFalse(readOnly);
+                listener.onResponse(null);
+            }
+
+            @Override
+            protected void setIndexCreateBlock(ActionListener<Void> listener, boolean indexCreateBlock) {
+                countBlocksCalled.set(countBlocksCalled.get() + 1);
+                listener.onResponse(null);
+            }
+        };
+
+        ImmutableOpenMap.Builder<String, DiskUsage> builder = ImmutableOpenMap.builder();
+        monitor.onNewInfo(clusterInfo(builder.build()));
+        assertTrue(countBlocksCalled.get() == 0);
+    }
+
     private void assertNoLogging(DiskThresholdMonitor monitor, ImmutableOpenMap<String, DiskUsage> diskUsages)
         throws IllegalAccessException {
         try (MockLogAppender mockAppender = MockLogAppender.createForLoggers(LogManager.getLogger(DiskThresholdMonitor.class))) {
diff --git a/server/src/test/java/org/opensearch/cluster/routing/allocation/FailedNodeRoutingTests.java b/server/src/test/java/org/opensearch/cluster/routing/allocation/FailedNodeRoutingTests.java
index b3d62ea9c6160..edef8d9747b8f 100644
--- a/server/src/test/java/org/opensearch/cluster/routing/allocation/FailedNodeRoutingTests.java
+++ b/server/src/test/java/org/opensearch/cluster/routing/allocation/FailedNodeRoutingTests.java
@@ -188,8 +188,9 @@ public void testRandomClusterPromotesNewestReplica() throws InterruptedException
             // Pick a random subset of primaries to fail
             List<FailedShard> shardsToFail = new ArrayList<>();
             List<ShardRouting> failedPrimaries = randomSubsetOf(primaries);
-            failedPrimaries.stream()
-                .forEach(sr -> { shardsToFail.add(new FailedShard(randomFrom(sr), "failed primary", new Exception(), randomBoolean())); });
+            failedPrimaries.stream().forEach(sr -> {
+                shardsToFail.add(new FailedShard(randomFrom(sr), "failed primary", new Exception(), randomBoolean()));
+            });
 
             logger.info("--> state before failing shards: {}", state);
             state = cluster.applyFailedShards(state, shardsToFail);
diff --git a/server/src/test/java/org/opensearch/cluster/routing/allocation/IndexShardConstraintDeciderOverlapTests.java b/server/src/test/java/org/opensearch/cluster/routing/allocation/IndexShardConstraintDeciderOverlapTests.java
index 773c82be55ead..24c6dcff42849 100644
--- a/server/src/test/java/org/opensearch/cluster/routing/allocation/IndexShardConstraintDeciderOverlapTests.java
+++ b/server/src/test/java/org/opensearch/cluster/routing/allocation/IndexShardConstraintDeciderOverlapTests.java
@@ -68,10 +68,10 @@ public void testHighWatermarkBreachWithLowShardCount() {
         final ImmutableOpenMap<ClusterInfo.NodeAndPath, ClusterInfo.ReservedSpace> reservedSpace = new ImmutableOpenMap.Builder<
             ClusterInfo.NodeAndPath,
             ClusterInfo.ReservedSpace>().fPut(getNodeAndDevNullPath("node_0"), getReservedSpace())
-                .fPut(getNodeAndDevNullPath("node_1"), getReservedSpace())
-                .fPut(getNodeAndDevNullPath("node_2"), getReservedSpace())
-                .fPut(getNodeAndDevNullPath("high_watermark_node_0"), getReservedSpace())
-                .build();
+            .fPut(getNodeAndDevNullPath("node_1"), getReservedSpace())
+            .fPut(getNodeAndDevNullPath("node_2"), getReservedSpace())
+            .fPut(getNodeAndDevNullPath("high_watermark_node_0"), getReservedSpace())
+            .build();
         final ClusterInfo clusterInfo = new DevNullClusterInfo(usages, usages, shardSizes, reservedSpace);
         ClusterInfoService cis = () -> clusterInfo;
         allocation = createAllocationService(settings, cis);
diff --git a/server/src/test/java/org/opensearch/cluster/routing/allocation/NodeLoadAwareAllocationTests.java b/server/src/test/java/org/opensearch/cluster/routing/allocation/NodeLoadAwareAllocationTests.java
index c4dcae84581cb..0d53e4bf8c4ed 100644
--- a/server/src/test/java/org/opensearch/cluster/routing/allocation/NodeLoadAwareAllocationTests.java
+++ b/server/src/test/java/org/opensearch/cluster/routing/allocation/NodeLoadAwareAllocationTests.java
@@ -28,6 +28,7 @@
 import org.opensearch.gateway.GatewayAllocator;
 import org.opensearch.test.gateway.TestGatewayAllocator;
 
+import java.util.List;
 import java.util.Map;
 
 import static java.util.Collections.singletonMap;
@@ -43,7 +44,7 @@ public class NodeLoadAwareAllocationTests extends OpenSearchAllocationTestCase {
 
     public void testNewUnassignedPrimaryAllocationOnOverload() {
         AllocationService strategy = createAllocationServiceWithAdditionalSettings(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_PROVISIONED_CAPACITY_SETTING.getKey(),
                 5,
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_SKEW_FACTOR_SETTING.getKey(),
@@ -136,7 +137,7 @@ public void testNewUnassignedPrimaryAllocationOnOverload() {
 
     public void testNoAllocationLimitsOnOverloadForDisabledLoadFactor() {
         AllocationService strategy = createAllocationServiceWithAdditionalSettings(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_PROVISIONED_CAPACITY_SETTING.getKey(),
                 5,
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_SKEW_FACTOR_SETTING.getKey(),
@@ -231,7 +232,7 @@ public void testNoAllocationLimitsOnOverloadForDisabledLoadFactor() {
     public void testExistingPrimariesAllocationOnOverload() {
         GatewayAllocator gatewayAllocator = new TestGatewayAllocator();
         AllocationService strategy = createAllocationServiceWithAdditionalSettings(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_PROVISIONED_CAPACITY_SETTING.getKey(),
                 5,
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_SKEW_FACTOR_SETTING.getKey(),
@@ -317,7 +318,7 @@ public void testExistingPrimariesAllocationOnOverload() {
 
         logger.info("--> change the overload load factor to zero and verify if unassigned primaries on disk get assigned despite overload");
         strategy = createAllocationServiceWithAdditionalSettings(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_PROVISIONED_CAPACITY_SETTING.getKey(),
                 5,
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_SKEW_FACTOR_SETTING.getKey(),
@@ -383,7 +384,7 @@ public void testExistingPrimariesAllocationOnOverload() {
     public void testSingleZoneOneReplicaLimitsShardAllocationOnOverload() {
         GatewayAllocator gatewayAllocator = new TestGatewayAllocator();
         AllocationService strategy = createAllocationServiceWithAdditionalSettings(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_PROVISIONED_CAPACITY_SETTING.getKey(),
                 5,
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_SKEW_FACTOR_SETTING.getKey(),
@@ -494,7 +495,7 @@ public void testSingleZoneOneReplicaLimitsShardAllocationOnOverload() {
 
         logger.info("change settings to allow unassigned primaries");
         strategy = createAllocationServiceWithAdditionalSettings(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_PROVISIONED_CAPACITY_SETTING.getKey(),
                 5,
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_SKEW_FACTOR_SETTING.getKey(),
@@ -534,7 +535,7 @@ public void testSingleZoneOneReplicaLimitsShardAllocationOnOverload() {
 
     public void testThreeZoneTwoReplicaLimitsShardAllocationOnOverload() {
         AllocationService strategy = createAllocationServiceWithAdditionalSettings(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_PROVISIONED_CAPACITY_SETTING.getKey(),
                 15,
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_SKEW_FACTOR_SETTING.getKey(),
@@ -643,7 +644,7 @@ public void testThreeZoneTwoReplicaLimitsShardAllocationOnOverload() {
 
     public void testThreeZoneOneReplicaLimitsShardAllocationOnOverload() {
         AllocationService strategy = createAllocationServiceWithAdditionalSettings(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_PROVISIONED_CAPACITY_SETTING.getKey(),
                 15,
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_SKEW_FACTOR_SETTING.getKey(),
@@ -738,7 +739,7 @@ public void testThreeZoneOneReplicaLimitsShardAllocationOnOverload() {
 
     public void testThreeZoneTwoReplicaLimitsShardAllocationOnOverloadAcrossZones() {
         AllocationService strategy = createAllocationServiceWithAdditionalSettings(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_PROVISIONED_CAPACITY_SETTING.getKey(),
                 9,
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_SKEW_FACTOR_SETTING.getKey(),
@@ -832,7 +833,7 @@ public void testThreeZoneTwoReplicaLimitsShardAllocationOnOverloadAcrossZones()
 
     public void testSingleZoneTwoReplicaLimitsReplicaAllocationOnOverload() {
         AllocationService strategy = createAllocationServiceWithAdditionalSettings(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_PROVISIONED_CAPACITY_SETTING.getKey(),
                 3,
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_SKEW_FACTOR_SETTING.getKey(),
@@ -893,7 +894,7 @@ public void testSingleZoneTwoReplicaLimitsReplicaAllocationOnOverload() {
 
     public void testSingleZoneOneReplicaLimitsReplicaAllocationOnOverload() {
         AllocationService strategy = createAllocationServiceWithAdditionalSettings(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_PROVISIONED_CAPACITY_SETTING.getKey(),
                 5,
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_SKEW_FACTOR_SETTING.getKey(),
@@ -976,7 +977,7 @@ public void testSingleZoneOneReplicaLimitsReplicaAllocationOnOverload() {
 
     public void testThreeZoneTwoReplicaLimitsReplicaAllocationUnderFullZoneFailure() {
         AllocationService strategy = createAllocationServiceWithAdditionalSettings(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_PROVISIONED_CAPACITY_SETTING.getKey(),
                 15,
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_SKEW_FACTOR_SETTING.getKey(),
@@ -1087,7 +1088,7 @@ public void testThreeZoneTwoReplicaLimitsReplicaAllocationUnderFullZoneFailure()
 
     public void testThreeZoneOneReplicaWithSkewFactorZeroAllShardsAssignedAfterRecovery() {
         AllocationService strategy = createAllocationServiceWithAdditionalSettings(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_PROVISIONED_CAPACITY_SETTING.getKey(),
                 15,
                 NodeLoadAwareAllocationDecider.CLUSTER_ROUTING_ALLOCATION_LOAD_AWARENESS_SKEW_FACTOR_SETTING.getKey(),
@@ -1201,13 +1202,13 @@ public void testThreeZoneOneReplicaWithSkewFactorZeroAllShardsAssignedAfterRecov
 
     private ClusterState removeNodes(ClusterState clusterState, AllocationService allocationService, String... nodeIds) {
         DiscoveryNodes.Builder nodeBuilder = DiscoveryNodes.builder(clusterState.getNodes());
-        org.opensearch.common.collect.List.of(nodeIds).forEach(nodeId -> nodeBuilder.remove(nodeId));
+        List.of(nodeIds).forEach(nodeId -> nodeBuilder.remove(nodeId));
         return allocationService.disassociateDeadNodes(ClusterState.builder(clusterState).nodes(nodeBuilder).build(), true, "reroute");
     }
 
     private ClusterState addNodes(ClusterState clusterState, AllocationService allocationService, String zone, String... nodeIds) {
         DiscoveryNodes.Builder nodeBuilder = DiscoveryNodes.builder(clusterState.nodes());
-        org.opensearch.common.collect.List.of(nodeIds).forEach(nodeId -> nodeBuilder.add(newNode(nodeId, singletonMap("zone", zone))));
+        List.of(nodeIds).forEach(nodeId -> nodeBuilder.add(newNode(nodeId, singletonMap("zone", zone))));
         clusterState = ClusterState.builder(clusterState).nodes(nodeBuilder).build();
         return allocationService.reroute(clusterState, "reroute");
     }
diff --git a/server/src/test/java/org/opensearch/cluster/routing/allocation/RemoteShardsBalancerBaseTestCase.java b/server/src/test/java/org/opensearch/cluster/routing/allocation/RemoteShardsBalancerBaseTestCase.java
index 789de474d8ce5..ae9799545e6af 100644
--- a/server/src/test/java/org/opensearch/cluster/routing/allocation/RemoteShardsBalancerBaseTestCase.java
+++ b/server/src/test/java/org/opensearch/cluster/routing/allocation/RemoteShardsBalancerBaseTestCase.java
@@ -20,7 +20,6 @@
 import org.opensearch.cluster.OpenSearchAllocationTestCase;
 import org.opensearch.cluster.metadata.IndexMetadata;
 import org.opensearch.cluster.metadata.Metadata;
-import org.opensearch.cluster.node.DiscoveryNode;
 import org.opensearch.cluster.node.DiscoveryNodeRole;
 import org.opensearch.cluster.node.DiscoveryNodes;
 import org.opensearch.cluster.routing.RoutingNodes;
@@ -35,18 +34,13 @@
 import org.opensearch.common.collect.ImmutableOpenMap;
 import org.opensearch.common.settings.ClusterSettings;
 import org.opensearch.common.settings.Settings;
-import org.opensearch.common.transport.TransportAddress;
 import org.opensearch.common.util.FeatureFlags;
 import org.opensearch.index.IndexModule;
 import org.opensearch.test.gateway.TestGatewayAllocator;
 
-import java.net.Inet4Address;
-import java.net.UnknownHostException;
 import java.util.ArrayList;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.List;
-import java.util.Map;
 import java.util.Set;
 
 import static org.opensearch.cluster.routing.ShardRoutingState.INITIALIZING;
@@ -66,6 +60,7 @@ public abstract class RemoteShardsBalancerBaseTestCase extends OpenSearchAllocat
         DiscoveryNodeRole.DATA_ROLE,
         DiscoveryNodeRole.SEARCH_ROLE
     );
+    protected static final Set<DiscoveryNodeRole> SEARCH_ONLY_ROLE = Set.of(DiscoveryNodeRole.SEARCH_ROLE);
 
     protected static final int PRIMARIES = 5;
     protected static final int REPLICAS = 1;
@@ -116,52 +111,11 @@ public RoutingAllocation getRoutingAllocation(ClusterState clusterState, Routing
         );
     }
 
-    private Map<String, String> createNodeAttributes(String nodeId) {
-        Map<String, String> attr = new HashMap<>();
-        attr.put("name", nodeId);
-        attr.put("node_id", nodeId);
-        return attr;
+    public ClusterState createInitialCluster(int localOnlyNodes, int remoteNodes, int localIndices, int remoteIndices) {
+        return createInitialCluster(localOnlyNodes, remoteNodes, false, localIndices, remoteIndices);
     }
 
-    public ClusterState addNodes(ClusterState clusterState, int nodeCount, boolean isRemote) {
-        DiscoveryNodes.Builder nb = DiscoveryNodes.builder(clusterState.nodes());
-        for (int i = 0; i < nodeCount; i++) {
-            String id = getNodeId(i, isRemote, "new");
-            nb.add(newNode(id, id, isRemote ? SEARCH_DATA_ROLES : MANAGER_DATA_ROLES));
-        }
-        return ClusterState.builder(clusterState).nodes(nb.build()).build();
-    }
-
-    public ClusterState addNodeWithIP(ClusterState clusterState, int nodeId, boolean isRemote, String IP) throws UnknownHostException {
-        TransportAddress ipAddress = new TransportAddress(Inet4Address.getByName(IP), 9200);
-        DiscoveryNodes.Builder nb = DiscoveryNodes.builder(clusterState.nodes());
-        String id = getNodeId(nodeId, isRemote, "new");
-        nb.add(
-            new DiscoveryNode(
-                id,
-                id,
-                ipAddress,
-                createNodeAttributes(id),
-                isRemote ? SEARCH_DATA_ROLES : MANAGER_DATA_ROLES,
-                Version.CURRENT
-            )
-        );
-        return ClusterState.builder(clusterState).nodes(nb.build()).build();
-    }
-
-    public ClusterState terminateNodes(ClusterState clusterState, AllocationService service, List<String> nodesToTerminate) {
-        if (nodesToTerminate.isEmpty()) {
-            return clusterState;
-        }
-        logger.info("Terminating following nodes from cluster: [{}]", nodesToTerminate);
-        DiscoveryNodes.Builder nb = DiscoveryNodes.builder(clusterState.nodes());
-        nodesToTerminate.forEach(nb::remove);
-        clusterState = ClusterState.builder(clusterState).nodes(nb.build()).build();
-        clusterState = service.disassociateDeadNodes(clusterState, false, "nodes-terminated");
-        return clusterState;
-    }
-
-    public ClusterState createInitialCluster(int localOnlyNodes, int remoteCapableNodes, int localIndices, int remoteIndices) {
+    public ClusterState createInitialCluster(int localOnlyNodes, int remoteNodes, boolean remoteOnly, int localIndices, int remoteIndices) {
         Metadata.Builder mb = Metadata.builder();
         for (int i = 0; i < localIndices; i++) {
             mb.put(
@@ -199,9 +153,16 @@ public ClusterState createInitialCluster(int localOnlyNodes, int remoteCapableNo
             String name = getNodeId(i, false);
             nb.add(newNode(name, name, MANAGER_DATA_ROLES));
         }
-        for (int i = 0; i < remoteCapableNodes; i++) {
-            String name = getNodeId(i, true);
-            nb.add(newNode(name, name, SEARCH_DATA_ROLES));
+        if (remoteOnly) {
+            for (int i = 0; i < remoteNodes; i++) {
+                String name = getNodeId(i, true);
+                nb.add(newNode(name, name, SEARCH_ONLY_ROLE));
+            }
+        } else {
+            for (int i = 0; i < remoteNodes; i++) {
+                String name = getNodeId(i, true);
+                nb.add(newNode(name, name, SEARCH_DATA_ROLES));
+            }
         }
         DiscoveryNodes nodes = nb.build();
         return ClusterState.builder(ClusterName.DEFAULT).metadata(metadata).routingTable(routingTable).nodes(nodes).build();
diff --git a/server/src/test/java/org/opensearch/cluster/routing/allocation/decider/TargetPoolAllocationDeciderTests.java b/server/src/test/java/org/opensearch/cluster/routing/allocation/decider/TargetPoolAllocationDeciderTests.java
index 9a415ed0b339b..8f2db5db969d2 100644
--- a/server/src/test/java/org/opensearch/cluster/routing/allocation/decider/TargetPoolAllocationDeciderTests.java
+++ b/server/src/test/java/org/opensearch/cluster/routing/allocation/decider/TargetPoolAllocationDeciderTests.java
@@ -24,7 +24,7 @@
 import java.util.stream.Collectors;
 
 public class TargetPoolAllocationDeciderTests extends RemoteShardsBalancerBaseTestCase {
-    public void testTargetPoolAllocationDecisions() {
+    public void testTargetPoolHybridAllocationDecisions() {
         ClusterState clusterState = createInitialCluster(3, 3, 2, 2);
         AllocationService service = this.createRemoteCapableAllocationService();
         clusterState = allocateShardsAndBalance(clusterState, service);
@@ -111,4 +111,93 @@ public void testTargetPoolAllocationDecisions() {
         assertEquals(Decision.YES.type(), deciders.shouldAutoExpandToNode(localIdx, localOnlyNode.node(), globalAllocation).type());
         assertEquals(Decision.YES.type(), deciders.shouldAutoExpandToNode(remoteIdx, remoteCapableNode.node(), globalAllocation).type());
     }
+
+    public void testTargetPoolDedicatedSearchNodeAllocationDecisions() {
+        ClusterState clusterState = createInitialCluster(3, 3, true, 2, 2);
+        AllocationService service = this.createRemoteCapableAllocationService();
+        clusterState = allocateShardsAndBalance(clusterState, service);
+
+        // Add an unassigned primary shard for force allocation checks
+        Metadata metadata = Metadata.builder(clusterState.metadata())
+            .put(IndexMetadata.builder("test_local_unassigned").settings(settings(Version.CURRENT)).numberOfShards(1).numberOfReplicas(1))
+            .build();
+        RoutingTable routingTable = RoutingTable.builder(clusterState.routingTable())
+            .addAsNew(metadata.index("test_local_unassigned"))
+            .build();
+        clusterState = ClusterState.builder(clusterState).metadata(metadata).routingTable(routingTable).build();
+
+        // Add remote index unassigned primary
+        clusterState = createRemoteIndex(clusterState, "test_remote_unassigned");
+
+        RoutingNodes defaultRoutingNodes = clusterState.getRoutingNodes();
+        RoutingAllocation globalAllocation = getRoutingAllocation(clusterState, defaultRoutingNodes);
+
+        ShardRouting localShard = clusterState.routingTable()
+            .allShards(getIndexName(0, false))
+            .stream()
+            .filter(ShardRouting::primary)
+            .collect(Collectors.toList())
+            .get(0);
+        ShardRouting remoteShard = clusterState.routingTable()
+            .allShards(getIndexName(0, true))
+            .stream()
+            .filter(ShardRouting::primary)
+            .collect(Collectors.toList())
+            .get(0);
+        ShardRouting unassignedLocalShard = clusterState.routingTable()
+            .allShards("test_local_unassigned")
+            .stream()
+            .filter(ShardRouting::primary)
+            .collect(Collectors.toList())
+            .get(0);
+        ShardRouting unassignedRemoteShard = clusterState.routingTable()
+            .allShards("test_remote_unassigned")
+            .stream()
+            .filter(ShardRouting::primary)
+            .collect(Collectors.toList())
+            .get(0);
+        IndexMetadata localIdx = globalAllocation.metadata().getIndexSafe(localShard.index());
+        IndexMetadata remoteIdx = globalAllocation.metadata().getIndexSafe(remoteShard.index());
+        String localNodeId = LOCAL_NODE_PREFIX;
+        for (RoutingNode routingNode : globalAllocation.routingNodes()) {
+            if (routingNode.nodeId().startsWith(LOCAL_NODE_PREFIX)) {
+                localNodeId = routingNode.nodeId();
+                break;
+            }
+        }
+        String remoteNodeId = remoteShard.currentNodeId();
+        RoutingNode localOnlyNode = defaultRoutingNodes.node(localNodeId);
+        RoutingNode remoteCapableNode = defaultRoutingNodes.node(remoteNodeId);
+
+        AllocationDeciders deciders = new AllocationDeciders(Collections.singletonList(new TargetPoolAllocationDecider()));
+
+        // Incompatible Pools
+        assertEquals(Decision.NO.type(), deciders.canAllocate(remoteShard, localOnlyNode, globalAllocation).type());
+        assertEquals(Decision.NO.type(), deciders.canAllocate(remoteIdx, localOnlyNode, globalAllocation).type());
+        assertEquals(Decision.NO.type(), deciders.canForceAllocatePrimary(unassignedRemoteShard, localOnlyNode, globalAllocation).type());
+        // A dedicated search node should not accept local shards and indices.
+        assertEquals(Decision.NO.type(), deciders.canAllocate(localShard, remoteCapableNode, globalAllocation).type());
+        assertEquals(Decision.NO.type(), deciders.canAllocate(localIdx, remoteCapableNode, globalAllocation).type());
+        assertEquals(
+            Decision.NO.type(),
+            deciders.canForceAllocatePrimary(unassignedLocalShard, remoteCapableNode, globalAllocation).type()
+        );
+
+        // Compatible Pools
+        assertEquals(Decision.YES.type(), deciders.canAllocate(remoteShard, remoteCapableNode, globalAllocation).type());
+        assertEquals(Decision.YES.type(), deciders.canAllocate(remoteIdx, remoteCapableNode, globalAllocation).type());
+        assertEquals(Decision.YES.type(), deciders.canAllocate(localShard, localOnlyNode, globalAllocation).type());
+        assertEquals(Decision.YES.type(), deciders.canAllocate(localIdx, localOnlyNode, globalAllocation).type());
+        assertEquals(
+            Decision.YES.type(),
+            deciders.canForceAllocatePrimary(unassignedRemoteShard, remoteCapableNode, globalAllocation).type()
+        );
+        assertEquals(Decision.YES.type(), deciders.canForceAllocatePrimary(unassignedLocalShard, localOnlyNode, globalAllocation).type());
+
+        // Verify only compatible nodes are used for auto expand replica decision for remote index and local index
+        assertEquals(Decision.NO.type(), deciders.shouldAutoExpandToNode(localIdx, remoteCapableNode.node(), globalAllocation).type());
+        assertEquals(Decision.NO.type(), deciders.shouldAutoExpandToNode(remoteIdx, localOnlyNode.node(), globalAllocation).type());
+        assertEquals(Decision.YES.type(), deciders.shouldAutoExpandToNode(localIdx, localOnlyNode.node(), globalAllocation).type());
+        assertEquals(Decision.YES.type(), deciders.shouldAutoExpandToNode(remoteIdx, remoteCapableNode.node(), globalAllocation).type());
+    }
 }
diff --git a/server/src/test/java/org/opensearch/cluster/service/ClusterManagerTaskThrottlerTests.java b/server/src/test/java/org/opensearch/cluster/service/ClusterManagerTaskThrottlerTests.java
index 0acdbffe3dc4f..7492ea80638ed 100644
--- a/server/src/test/java/org/opensearch/cluster/service/ClusterManagerTaskThrottlerTests.java
+++ b/server/src/test/java/org/opensearch/cluster/service/ClusterManagerTaskThrottlerTests.java
@@ -69,12 +69,9 @@ public static void afterClass() {
 
     public void testDefaults() {
         ClusterSettings clusterSettings = new ClusterSettings(Settings.builder().build(), ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
-        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(
-            Settings.EMPTY,
-            clusterSettings,
-            () -> { return clusterService.getMasterService().getMinNodeVersion(); },
-            new ClusterManagerThrottlingStats()
-        );
+        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(Settings.EMPTY, clusterSettings, () -> {
+            return clusterService.getMasterService().getMinNodeVersion();
+        }, new ClusterManagerThrottlingStats());
         throttler.registerClusterManagerTask("put-mapping", true);
         throttler.registerClusterManagerTask("create-index", true);
         for (String key : throttler.THROTTLING_TASK_KEYS.keySet()) {
@@ -91,12 +88,9 @@ public void testValidateSettingsForDifferentVersion() {
         );
 
         ClusterSettings clusterSettings = new ClusterSettings(Settings.builder().build(), ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
-        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(
-            Settings.EMPTY,
-            clusterSettings,
-            () -> { return clusterService.getMasterService().getMinNodeVersion(); },
-            new ClusterManagerThrottlingStats()
-        );
+        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(Settings.EMPTY, clusterSettings, () -> {
+            return clusterService.getMasterService().getMinNodeVersion();
+        }, new ClusterManagerThrottlingStats());
         throttler.registerClusterManagerTask("put-mapping", true);
 
         // set some limit for update snapshot tasks
@@ -124,12 +118,9 @@ public void testValidateSettingsForTaskWihtoutRetryOnDataNode() {
         );
 
         ClusterSettings clusterSettings = new ClusterSettings(Settings.builder().build(), ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
-        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(
-            Settings.EMPTY,
-            clusterSettings,
-            () -> { return clusterService.getMasterService().getMinNodeVersion(); },
-            new ClusterManagerThrottlingStats()
-        );
+        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(Settings.EMPTY, clusterSettings, () -> {
+            return clusterService.getMasterService().getMinNodeVersion();
+        }, new ClusterManagerThrottlingStats());
         throttler.registerClusterManagerTask("put-mapping", false);
 
         // set some limit for update snapshot tasks
@@ -148,12 +139,9 @@ public void testUpdateSettingsForNullValue() {
         );
 
         ClusterSettings clusterSettings = new ClusterSettings(Settings.builder().build(), ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
-        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(
-            Settings.EMPTY,
-            clusterSettings,
-            () -> { return clusterService.getMasterService().getMinNodeVersion(); },
-            new ClusterManagerThrottlingStats()
-        );
+        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(Settings.EMPTY, clusterSettings, () -> {
+            return clusterService.getMasterService().getMinNodeVersion();
+        }, new ClusterManagerThrottlingStats());
         throttler.registerClusterManagerTask("put-mapping", true);
 
         // set some limit for put-mapping tasks
@@ -181,12 +169,9 @@ public void testSettingsOnBootstrap() {
         Settings initialSettings = Settings.builder()
             .put("cluster_manager.throttling.thresholds.put-mapping.value", put_mapping_threshold_value)
             .build();
-        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(
-            initialSettings,
-            clusterSettings,
-            () -> { return clusterService.getMasterService().getMinNodeVersion(); },
-            new ClusterManagerThrottlingStats()
-        );
+        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(initialSettings, clusterSettings, () -> {
+            return clusterService.getMasterService().getMinNodeVersion();
+        }, new ClusterManagerThrottlingStats());
         throttler.registerClusterManagerTask("put-mapping", true);
 
         // assert that limit is applied on throttler
@@ -202,12 +187,9 @@ public void testValidateSettingsForUnknownTask() {
         );
 
         ClusterSettings clusterSettings = new ClusterSettings(Settings.builder().build(), ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
-        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(
-            Settings.EMPTY,
-            clusterSettings,
-            () -> { return clusterService.getMasterService().getMinNodeVersion(); },
-            new ClusterManagerThrottlingStats()
-        );
+        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(Settings.EMPTY, clusterSettings, () -> {
+            return clusterService.getMasterService().getMinNodeVersion();
+        }, new ClusterManagerThrottlingStats());
 
         // set some limit for update snapshot tasks
         int newLimit = randomIntBetween(1, 10);
@@ -224,12 +206,9 @@ public void testUpdateThrottlingLimitForBasicSanity() {
         );
 
         ClusterSettings clusterSettings = new ClusterSettings(Settings.builder().build(), ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
-        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(
-            Settings.EMPTY,
-            clusterSettings,
-            () -> { return clusterService.getMasterService().getMinNodeVersion(); },
-            new ClusterManagerThrottlingStats()
-        );
+        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(Settings.EMPTY, clusterSettings, () -> {
+            return clusterService.getMasterService().getMinNodeVersion();
+        }, new ClusterManagerThrottlingStats());
         throttler.registerClusterManagerTask("put-mapping", true);
 
         // set some limit for update snapshot tasks
@@ -254,12 +233,9 @@ public void testValidateSettingForLimit() {
         );
 
         ClusterSettings clusterSettings = new ClusterSettings(Settings.builder().build(), ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
-        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(
-            Settings.EMPTY,
-            clusterSettings,
-            () -> { return clusterService.getMasterService().getMinNodeVersion(); },
-            new ClusterManagerThrottlingStats()
-        );
+        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(Settings.EMPTY, clusterSettings, () -> {
+            return clusterService.getMasterService().getMinNodeVersion();
+        }, new ClusterManagerThrottlingStats());
         throttler.registerClusterManagerTask("put-mapping", true);
 
         Settings newSettings = Settings.builder().put("cluster_manager.throttling.thresholds.put-mapping.values", -5).build();
@@ -268,12 +244,9 @@ public void testValidateSettingForLimit() {
 
     public void testUpdateLimit() {
         ClusterSettings clusterSettings = new ClusterSettings(Settings.builder().build(), ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
-        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(
-            Settings.EMPTY,
-            clusterSettings,
-            () -> { return clusterService.getMasterService().getMinNodeVersion(); },
-            new ClusterManagerThrottlingStats()
-        );
+        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(Settings.EMPTY, clusterSettings, () -> {
+            return clusterService.getMasterService().getMinNodeVersion();
+        }, new ClusterManagerThrottlingStats());
         throttler.registerClusterManagerTask("put-mapping", true);
 
         throttler.updateLimit("test", 5);
@@ -306,12 +279,9 @@ public void testThrottlingForDisabledThrottlingTask() {
         ClusterManagerThrottlingStats throttlingStats = new ClusterManagerThrottlingStats();
         String taskKey = "test";
         ClusterSettings clusterSettings = new ClusterSettings(Settings.builder().build(), ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
-        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(
-            Settings.EMPTY,
-            clusterSettings,
-            () -> { return clusterService.getMasterService().getMinNodeVersion(); },
-            throttlingStats
-        );
+        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(Settings.EMPTY, clusterSettings, () -> {
+            return clusterService.getMasterService().getMinNodeVersion();
+        }, throttlingStats);
         ClusterManagerTaskThrottler.ThrottlingKey throttlingKey = throttler.registerClusterManagerTask(taskKey, false);
 
         // adding limit directly in thresholds
@@ -339,12 +309,9 @@ public void testThrottlingForInitialStaticSettingAndVersionCheck() {
         Settings initialSettings = Settings.builder()
             .put("cluster_manager.throttling.thresholds.put-mapping.value", put_mapping_threshold_value)
             .build();
-        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(
-            initialSettings,
-            clusterSettings,
-            () -> { return clusterService.getMasterService().getMinNodeVersion(); },
-            throttlingStats
-        );
+        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(initialSettings, clusterSettings, () -> {
+            return clusterService.getMasterService().getMinNodeVersion();
+        }, throttlingStats);
         ClusterManagerTaskThrottler.ThrottlingKey throttlingKey = throttler.registerClusterManagerTask("put-mapping", true);
 
         // verifying adding more tasks then threshold passes
@@ -370,12 +337,9 @@ public void testThrottling() {
         ClusterManagerThrottlingStats throttlingStats = new ClusterManagerThrottlingStats();
         String taskKey = "test";
         ClusterSettings clusterSettings = new ClusterSettings(Settings.builder().build(), ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
-        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(
-            Settings.EMPTY,
-            clusterSettings,
-            () -> { return clusterService.getMasterService().getMinNodeVersion(); },
-            throttlingStats
-        );
+        ClusterManagerTaskThrottler throttler = new ClusterManagerTaskThrottler(Settings.EMPTY, clusterSettings, () -> {
+            return clusterService.getMasterService().getMinNodeVersion();
+        }, throttlingStats);
         ClusterManagerTaskThrottler.ThrottlingKey throttlingKey = throttler.registerClusterManagerTask(taskKey, true);
 
         throttler.updateLimit(taskKey, 5);
diff --git a/server/src/test/java/org/opensearch/cluster/service/TaskBatcherTests.java b/server/src/test/java/org/opensearch/cluster/service/TaskBatcherTests.java
index 31018d4cef029..b59b70ca60ef8 100644
--- a/server/src/test/java/org/opensearch/cluster/service/TaskBatcherTests.java
+++ b/server/src/test/java/org/opensearch/cluster/service/TaskBatcherTests.java
@@ -279,6 +279,87 @@ public void processed(String source) {
         }
     }
 
+    public void testNoTasksAreDroppedInParallelSubmission() throws BrokenBarrierException, InterruptedException {
+        int numberOfThreads = randomIntBetween(2, 8);
+        TaskExecutor[] executors = new TaskExecutor[numberOfThreads];
+        for (int i = 0; i < numberOfThreads; i++) {
+            executors[i] = new TaskExecutor();
+        }
+
+        int tasksSubmittedPerThread = randomIntBetween(2, 1024);
+
+        CopyOnWriteArrayList<Tuple<String, Throwable>> failures = new CopyOnWriteArrayList<>();
+        CountDownLatch updateLatch = new CountDownLatch(numberOfThreads * tasksSubmittedPerThread);
+
+        final TestListener listener = new TestListener() {
+            @Override
+            public void onFailure(String source, Exception e) {
+                logger.error(() -> new ParameterizedMessage("unexpected failure: [{}]", source), e);
+                failures.add(new Tuple<>(source, e));
+                updateLatch.countDown();
+            }
+
+            @Override
+            public void processed(String source) {
+                updateLatch.countDown();
+            }
+        };
+
+        CyclicBarrier barrier = new CyclicBarrier(1 + numberOfThreads);
+
+        for (int i = 0; i < numberOfThreads; i++) {
+            final int index = i;
+            Thread thread = new Thread(() -> {
+                try {
+                    barrier.await();
+                    CyclicBarrier tasksBarrier = new CyclicBarrier(1 + tasksSubmittedPerThread);
+                    for (int j = 0; j < tasksSubmittedPerThread; j++) {
+                        int taskNumber = j;
+                        Thread taskThread = new Thread(() -> {
+                            try {
+                                tasksBarrier.await();
+                                submitTask(
+                                    "[" + index + "][" + taskNumber + "]",
+                                    taskNumber,
+                                    ClusterStateTaskConfig.build(randomFrom(Priority.values())),
+                                    executors[index],
+                                    listener
+                                );
+                                tasksBarrier.await();
+                            } catch (InterruptedException | BrokenBarrierException e) {
+                                throw new AssertionError(e);
+                            }
+                        });
+                        // submit tasks per batchingKey in parallel
+                        taskThread.start();
+                    }
+                    // wait for all task threads to be ready
+                    tasksBarrier.await();
+                    // wait for all task threads to finish
+                    tasksBarrier.await();
+                    barrier.await();
+                } catch (InterruptedException | BrokenBarrierException e) {
+                    throw new AssertionError(e);
+                }
+            });
+            thread.start();
+        }
+
+        // wait for all executor threads to be ready
+        barrier.await();
+        // wait for all executor threads to finish
+        barrier.await();
+
+        updateLatch.await();
+
+        assertThat(failures, empty());
+
+        for (int i = 0; i < numberOfThreads; i++) {
+            // assert that total executed tasks is same for every executor as we initiated
+            assertEquals(tasksSubmittedPerThread, executors[i].tasks.size());
+        }
+    }
+
     public void testSingleBatchSubmission() throws InterruptedException {
         Map<Integer, TestListener> tasks = new HashMap<>();
         final int numOfTasks = randomInt(10);
diff --git a/server/src/test/java/org/opensearch/common/geo/GeoJsonSerializationTests.java b/server/src/test/java/org/opensearch/common/geo/GeoJsonSerializationTests.java
index 2b943a65ef4d8..589b4d7597947 100644
--- a/server/src/test/java/org/opensearch/common/geo/GeoJsonSerializationTests.java
+++ b/server/src/test/java/org/opensearch/common/geo/GeoJsonSerializationTests.java
@@ -102,7 +102,9 @@ private void xContentTest(Supplier<Geometry> instanceSupplier) throws IOExceptio
         AbstractXContentTestCase.xContentTester(
             this::createParser,
             () -> new GeometryWrapper(instanceSupplier.get()),
-            (geometryWrapper, xContentBuilder) -> { geometryWrapper.toXContent(xContentBuilder, ToXContent.EMPTY_PARAMS); },
+            (geometryWrapper, xContentBuilder) -> {
+                geometryWrapper.toXContent(xContentBuilder, ToXContent.EMPTY_PARAMS);
+            },
             GeometryWrapper::fromXContent
         ).supportsUnknownFields(true).test();
     }
diff --git a/server/src/test/java/org/opensearch/common/settings/SettingTests.java b/server/src/test/java/org/opensearch/common/settings/SettingTests.java
index 7703cb394397e..005c0d7c38b51 100644
--- a/server/src/test/java/org/opensearch/common/settings/SettingTests.java
+++ b/server/src/test/java/org/opensearch/common/settings/SettingTests.java
@@ -36,9 +36,21 @@
 import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.core.LogEvent;
 import org.opensearch.cluster.metadata.IndexMetadata;
+import org.opensearch.common.bytes.BytesReference;
 import org.opensearch.common.collect.Tuple;
+import org.opensearch.common.io.stream.BytesStreamInput;
+import org.opensearch.common.io.stream.BytesStreamOutput;
 import org.opensearch.common.settings.AbstractScopedSettings.SettingUpdater;
+import org.opensearch.common.settings.Setting.ByteSizeValueParser;
+import org.opensearch.common.settings.Setting.DoubleParser;
+import org.opensearch.common.settings.Setting.FloatParser;
+import org.opensearch.common.settings.Setting.IntegerParser;
+import org.opensearch.common.settings.Setting.LongParser;
+import org.opensearch.common.settings.Setting.MemorySizeValueParser;
+import org.opensearch.common.settings.Setting.MinMaxTimeValueParser;
+import org.opensearch.common.settings.Setting.MinTimeValueParser;
 import org.opensearch.common.settings.Setting.Property;
+import org.opensearch.common.settings.Setting.RegexValidator;
 import org.opensearch.common.unit.ByteSizeUnit;
 import org.opensearch.common.unit.ByteSizeValue;
 import org.opensearch.common.unit.TimeValue;
@@ -58,6 +70,7 @@
 import java.util.function.BiConsumer;
 import java.util.function.Consumer;
 import java.util.function.Function;
+import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
@@ -311,14 +324,52 @@ public void testValidator() {
         assertTrue(FooBarValidator.invokedWithDependencies);
     }
 
+    public void testRegexValidator() throws Exception {
+        // A regex that matches one or more digits
+        String expectedRegex = "\\d+";
+        Pattern expectedPattern = Pattern.compile(expectedRegex);
+        RegexValidator regexValidator = new RegexValidator(expectedRegex);
+
+        // Test that the pattern is correctly initialized
+        assertNotNull(expectedPattern);
+        assertNotNull(regexValidator.getPattern());
+        assertEquals(expectedPattern.pattern(), regexValidator.getPattern().pattern());
+
+        // Test that validate() throws an exception for invalid input
+        final RegexValidator finalValidator = new RegexValidator(expectedRegex);
+        assertThrows(IllegalArgumentException.class, () -> finalValidator.validate("foo"));
+
+        try {
+            regexValidator.validate("123");
+        } catch (IllegalArgumentException e) {
+            fail("Expected validate() to not throw an exception, but it threw " + e);
+        }
+
+        try (BytesStreamOutput out = new BytesStreamOutput()) {
+            regexValidator.writeTo(out);
+            out.flush();
+            try (BytesStreamInput in = new BytesStreamInput(BytesReference.toBytes(out.bytes()))) {
+                regexValidator = new RegexValidator(in);
+                assertEquals(expectedPattern.pattern(), regexValidator.getPattern().pattern());
+
+                // Test that validate() throws an exception for invalid input
+                final RegexValidator newFinalValidator = new RegexValidator(expectedRegex);
+                assertThrows(IllegalArgumentException.class, () -> newFinalValidator.validate("foo"));
+
+                // Test that validate() does not throw an exception for valid input
+                try {
+                    regexValidator.validate("123");
+                } catch (IllegalArgumentException e) {
+                    fail("Expected validate() to not throw an exception, but it threw " + e);
+                }
+            }
+        }
+    }
+
     public void testValidatorForFilteredStringSetting() {
-        final Setting<String> filteredStringSetting = new Setting<>(
-            "foo.bar",
-            "foobar",
-            Function.identity(),
-            value -> { throw new SettingsException("validate always fails"); },
-            Property.Filtered
-        );
+        final Setting<String> filteredStringSetting = new Setting<>("foo.bar", "foobar", Function.identity(), value -> {
+            throw new SettingsException("validate always fails");
+        }, Property.Filtered);
 
         final Settings settings = Settings.builder().put(filteredStringSetting.getKey(), filteredStringSetting.getKey() + " value").build();
         final IllegalArgumentException e = expectThrows(IllegalArgumentException.class, () -> filteredStringSetting.get(settings));
@@ -1045,6 +1096,31 @@ public void testIntWithMinMax() {
         assertEquals(1, integerSetting.get(Settings.EMPTY).intValue());
     }
 
+    public void testIntegerParser() throws Exception {
+        String expectedKey = "test key";
+        int expectedMinValue = Integer.MIN_VALUE;
+        int expectedMaxValue = Integer.MAX_VALUE;
+        boolean expectedFilteredStatus = true;
+        IntegerParser integerParser = new IntegerParser(expectedMinValue, expectedMaxValue, expectedKey, expectedFilteredStatus);
+
+        assertEquals(expectedKey, integerParser.getKey());
+        assertEquals(expectedMinValue, integerParser.getMin());
+        assertEquals(expectedMaxValue, integerParser.getMax());
+        assertEquals(expectedFilteredStatus, integerParser.getFilterStatus());
+
+        try (BytesStreamOutput out = new BytesStreamOutput()) {
+            integerParser.writeTo(out);
+            out.flush();
+            try (BytesStreamInput in = new BytesStreamInput(BytesReference.toBytes(out.bytes()))) {
+                integerParser = new IntegerParser(in);
+                assertEquals(expectedKey, integerParser.getKey());
+                assertEquals(expectedMinValue, integerParser.getMin());
+                assertEquals(expectedMaxValue, integerParser.getMax());
+                assertEquals(expectedFilteredStatus, integerParser.getFilterStatus());
+            }
+        }
+    }
+
     // Long
 
     public void testLongWithDefaultValue() {
@@ -1080,6 +1156,31 @@ public void testLongWithMinMax() {
         assertEquals(1, longSetting.get(Settings.EMPTY).longValue());
     }
 
+    public void testLongParser() throws Exception {
+        String expectedKey = "test key";
+        long expectedMinValue = Long.MIN_VALUE;
+        long expectedMaxValue = Long.MAX_VALUE;
+        boolean expectedFilteredStatus = true;
+        LongParser longParser = new LongParser(expectedMinValue, expectedMaxValue, expectedKey, expectedFilteredStatus);
+
+        assertEquals(expectedKey, longParser.getKey());
+        assertEquals(expectedMinValue, longParser.getMin());
+        assertEquals(expectedMaxValue, longParser.getMax());
+        assertEquals(expectedFilteredStatus, longParser.getFilterStatus());
+
+        try (BytesStreamOutput out = new BytesStreamOutput()) {
+            longParser.writeTo(out);
+            out.flush();
+            try (BytesStreamInput in = new BytesStreamInput(BytesReference.toBytes(out.bytes()))) {
+                longParser = new LongParser(in);
+                assertEquals(expectedKey, longParser.getKey());
+                assertEquals(expectedMinValue, longParser.getMin());
+                assertEquals(expectedMaxValue, longParser.getMax());
+                assertEquals(expectedFilteredStatus, longParser.getFilterStatus());
+            }
+        }
+    }
+
     // Float
 
     public void testFloatWithDefaultValue() {
@@ -1115,6 +1216,31 @@ public void testFloatWithMinMax() {
         assertEquals(1.2, floatSetting.get(Settings.EMPTY).floatValue(), 0.01);
     }
 
+    public void testFloatParser() throws Exception {
+        String expectedKey = "test key";
+        float expectedMinValue = Float.MIN_VALUE;
+        float expectedMaxValue = Float.MAX_VALUE;
+        boolean expectedFilteredStatus = true;
+        FloatParser floatParser = new FloatParser(expectedMinValue, expectedMaxValue, expectedKey, expectedFilteredStatus);
+
+        assertEquals(expectedKey, floatParser.getKey());
+        assertEquals(expectedMinValue, floatParser.getMin(), 0.01);
+        assertEquals(expectedMaxValue, floatParser.getMax(), 0.01);
+        assertEquals(expectedFilteredStatus, floatParser.getFilterStatus());
+
+        try (BytesStreamOutput out = new BytesStreamOutput()) {
+            floatParser.writeTo(out);
+            out.flush();
+            try (BytesStreamInput in = new BytesStreamInput(BytesReference.toBytes(out.bytes()))) {
+                floatParser = new FloatParser(in);
+                assertEquals(expectedKey, floatParser.getKey());
+                assertEquals(expectedMinValue, floatParser.getMin(), 0.01);
+                assertEquals(expectedMaxValue, floatParser.getMax(), 0.01);
+                assertEquals(expectedFilteredStatus, floatParser.getFilterStatus());
+            }
+        }
+    }
+
     // Double
 
     public void testDoubleWithDefaultValue() {
@@ -1130,7 +1256,7 @@ public void testDoubleWithFallbackValue() {
         assertEquals(doubleSetting.get(Settings.builder().put("foo.baz", 3.2).build()), Double.valueOf(3.2));
     }
 
-    public void testDoubleWithMinMax() {
+    public void testDoubleWithMinMax() throws Exception {
         Setting<Double> doubleSetting = Setting.doubleSetting("foo.bar", 1.2, 0, 10, Property.NodeScope);
         try {
             doubleSetting.get(Settings.builder().put("foo.bar", 11.3).build());
@@ -1150,6 +1276,71 @@ public void testDoubleWithMinMax() {
         assertEquals(1.2, doubleSetting.get(Settings.EMPTY).doubleValue(), 0.01);
     }
 
+    public void testDoubleParser() throws Exception {
+        String expectedKey = "test key";
+        double expectedMinValue = Double.MIN_VALUE;
+        double expectedMaxValue = Double.MAX_VALUE;
+        boolean expectedFilteredStatus = true;
+        DoubleParser doubleParser = new DoubleParser(expectedMinValue, expectedMaxValue, expectedKey, expectedFilteredStatus);
+
+        assertEquals(expectedKey, doubleParser.getKey());
+        assertEquals(expectedMinValue, doubleParser.getMin(), 0.01);
+        assertEquals(expectedMaxValue, doubleParser.getMax(), 0.01);
+        assertEquals(expectedFilteredStatus, doubleParser.getFilterStatus());
+
+        try (BytesStreamOutput out = new BytesStreamOutput()) {
+            doubleParser.writeTo(out);
+            out.flush();
+            try (BytesStreamInput in = new BytesStreamInput(BytesReference.toBytes(out.bytes()))) {
+                doubleParser = new DoubleParser(in);
+                assertEquals(expectedKey, doubleParser.getKey());
+                assertEquals(expectedMinValue, doubleParser.getMin(), 0.01);
+                assertEquals(expectedMaxValue, doubleParser.getMax(), 0.01);
+                assertEquals(expectedFilteredStatus, doubleParser.getFilterStatus());
+            }
+        }
+    }
+
+    // ByteSizeValue
+    public void testByteSizeValueParser() throws Exception {
+        String expectedKey = "test key";
+        ByteSizeValue expectedMinValue = new ByteSizeValue((long) 1);
+        ByteSizeValue expectedMaxValue = new ByteSizeValue(Long.MAX_VALUE);
+        ByteSizeValueParser byteSizeValueParser = new ByteSizeValueParser(expectedMinValue, expectedMaxValue, expectedKey);
+
+        assertEquals(expectedKey, byteSizeValueParser.getKey());
+        assertEquals(expectedMinValue, byteSizeValueParser.getMin());
+        assertEquals(expectedMaxValue, byteSizeValueParser.getMax());
+
+        try (BytesStreamOutput out = new BytesStreamOutput()) {
+            byteSizeValueParser.writeTo(out);
+            out.flush();
+            try (BytesStreamInput in = new BytesStreamInput(BytesReference.toBytes(out.bytes()))) {
+                byteSizeValueParser = new ByteSizeValueParser(in);
+                assertEquals(expectedKey, byteSizeValueParser.getKey());
+                assertEquals(expectedMinValue, byteSizeValueParser.getMin());
+                assertEquals(expectedMaxValue, byteSizeValueParser.getMax());
+            }
+        }
+    }
+
+    // MemorySizeValue
+    public void testMemorySizeValueParser() throws Exception {
+        String expectedKey = "test key";
+        MemorySizeValueParser memorySizeValueParser = new MemorySizeValueParser(expectedKey);
+
+        assertEquals(expectedKey, memorySizeValueParser.getKey());
+
+        try (BytesStreamOutput out = new BytesStreamOutput()) {
+            memorySizeValueParser.writeTo(out);
+            out.flush();
+            try (BytesStreamInput in = new BytesStreamInput(BytesReference.toBytes(out.bytes()))) {
+                memorySizeValueParser = new MemorySizeValueParser(in);
+                assertEquals(expectedKey, memorySizeValueParser.getKey());
+            }
+        }
+    }
+
     /**
      * Only one single scope can be added to any setting
      */
@@ -1228,6 +1419,58 @@ public void testTimeValue() {
         assertThat(setting.get(Settings.EMPTY).getMillis(), equalTo(random.getMillis() * factor));
     }
 
+    public void testMinTimeValueParser() throws Exception {
+        String expectedKey = "test key";
+        TimeValue expectedMinValue = TimeValue.timeValueSeconds(0);
+        boolean expectedFilteredStatus = true;
+        MinTimeValueParser minTimeValueParser = new MinTimeValueParser(expectedKey, expectedMinValue, expectedFilteredStatus);
+
+        assertEquals(expectedKey, minTimeValueParser.getKey());
+        assertEquals(expectedMinValue, minTimeValueParser.getMin());
+        assertEquals(expectedFilteredStatus, minTimeValueParser.getFilterStatus());
+
+        try (BytesStreamOutput out = new BytesStreamOutput()) {
+            minTimeValueParser.writeTo(out);
+            out.flush();
+            try (BytesStreamInput in = new BytesStreamInput(BytesReference.toBytes(out.bytes()))) {
+                minTimeValueParser = new MinTimeValueParser(in);
+                assertEquals(expectedKey, minTimeValueParser.getKey());
+                assertEquals(expectedMinValue, minTimeValueParser.getMin());
+                assertEquals(expectedFilteredStatus, minTimeValueParser.getFilterStatus());
+            }
+        }
+    }
+
+    public void testMinMaxTimeValueParser() throws Exception {
+        String expectedKey = "test key";
+        TimeValue expectedMinValue = TimeValue.timeValueSeconds(0);
+        TimeValue expectedMaxValue = TimeValue.MAX_VALUE;
+        boolean expectedFilteredStatus = true;
+        MinMaxTimeValueParser minMaxTimeValueParser = new MinMaxTimeValueParser(
+            expectedKey,
+            expectedMinValue,
+            expectedMaxValue,
+            expectedFilteredStatus
+        );
+
+        assertEquals(expectedKey, minMaxTimeValueParser.getKey());
+        assertEquals(expectedMinValue, minMaxTimeValueParser.getMin());
+        assertEquals(expectedMaxValue, minMaxTimeValueParser.getMax());
+        assertEquals(expectedFilteredStatus, minMaxTimeValueParser.getFilterStatus());
+
+        try (BytesStreamOutput out = new BytesStreamOutput()) {
+            minMaxTimeValueParser.writeTo(out);
+            out.flush();
+            try (BytesStreamInput in = new BytesStreamInput(BytesReference.toBytes(out.bytes()))) {
+                minMaxTimeValueParser = new MinMaxTimeValueParser(in);
+                assertEquals(expectedKey, minMaxTimeValueParser.getKey());
+                assertEquals(expectedMinValue, minMaxTimeValueParser.getMin());
+                assertEquals(expectedMaxValue, minMaxTimeValueParser.getMax());
+                assertEquals(expectedFilteredStatus, minMaxTimeValueParser.getFilterStatus());
+            }
+        }
+    }
+
     public void testTimeValueBounds() {
         Setting<TimeValue> settingWithLowerBound = Setting.timeSetting(
             "foo",
@@ -1381,16 +1624,14 @@ public void testGroupSettingUpdaterValidator() {
             validator
         );
 
-        IllegalArgumentException illegal = expectThrows(
-            IllegalArgumentException.class,
-            () -> { updater.getValue(Settings.builder().put("prefix.foo.suffix", 5).put("abc", 2).build(), Settings.EMPTY); }
-        );
+        IllegalArgumentException illegal = expectThrows(IllegalArgumentException.class, () -> {
+            updater.getValue(Settings.builder().put("prefix.foo.suffix", 5).put("abc", 2).build(), Settings.EMPTY);
+        });
         assertEquals("foo and 2 can't go together", illegal.getMessage());
 
-        illegal = expectThrows(
-            IllegalArgumentException.class,
-            () -> { updater.getValue(Settings.builder().put("prefix.bar.suffix", 6).put("abc", 3).build(), Settings.EMPTY); }
-        );
+        illegal = expectThrows(IllegalArgumentException.class, () -> {
+            updater.getValue(Settings.builder().put("prefix.bar.suffix", 6).put("abc", 3).build(), Settings.EMPTY);
+        });
         assertEquals("no bar", illegal.getMessage());
 
         Settings s = updater.getValue(
diff --git a/server/src/test/java/org/opensearch/common/settings/SettingsTests.java b/server/src/test/java/org/opensearch/common/settings/SettingsTests.java
index 6848cd2bbc773..523659f00a1a3 100644
--- a/server/src/test/java/org/opensearch/common/settings/SettingsTests.java
+++ b/server/src/test/java/org/opensearch/common/settings/SettingsTests.java
@@ -606,19 +606,17 @@ public void testYamlLegacyList() throws IOException {
 
     public void testIndentation() throws Exception {
         String yaml = "/org/opensearch/common/settings/loader/indentation-settings.yml";
-        OpenSearchParseException e = expectThrows(
-            OpenSearchParseException.class,
-            () -> { Settings.builder().loadFromStream(yaml, getClass().getResourceAsStream(yaml), false); }
-        );
+        OpenSearchParseException e = expectThrows(OpenSearchParseException.class, () -> {
+            Settings.builder().loadFromStream(yaml, getClass().getResourceAsStream(yaml), false);
+        });
         assertTrue(e.getMessage(), e.getMessage().contains("malformed"));
     }
 
     public void testIndentationWithExplicitDocumentStart() throws Exception {
         String yaml = "/org/opensearch/common/settings/loader/indentation-with-explicit-document-start-settings.yml";
-        OpenSearchParseException e = expectThrows(
-            OpenSearchParseException.class,
-            () -> { Settings.builder().loadFromStream(yaml, getClass().getResourceAsStream(yaml), false); }
-        );
+        OpenSearchParseException e = expectThrows(OpenSearchParseException.class, () -> {
+            Settings.builder().loadFromStream(yaml, getClass().getResourceAsStream(yaml), false);
+        });
         assertTrue(e.getMessage(), e.getMessage().contains("malformed"));
     }
 
diff --git a/server/src/test/java/org/opensearch/common/unit/FuzzinessTests.java b/server/src/test/java/org/opensearch/common/unit/FuzzinessTests.java
index 9b8eb79112953..c2704391d6a74 100644
--- a/server/src/test/java/org/opensearch/common/unit/FuzzinessTests.java
+++ b/server/src/test/java/org/opensearch/common/unit/FuzzinessTests.java
@@ -31,6 +31,7 @@
 
 package org.opensearch.common.unit;
 
+import org.opensearch.OpenSearchParseException;
 import org.opensearch.common.io.stream.BytesStreamOutput;
 import org.opensearch.common.io.stream.StreamInput;
 import org.opensearch.common.xcontent.XContentBuilder;
@@ -138,6 +139,26 @@ public void testParseFromXContent() throws IOException {
 
     }
 
+    public void testFuzzinessValidationWithStrings() throws IOException {
+        String[] invalidStrings = new String[] { "+++", "asdfghjkl", "2k23" };
+        XContentBuilder json = jsonBuilder().startObject().field(Fuzziness.X_FIELD_NAME, randomFrom(invalidStrings)).endObject();
+        try (XContentParser parser = createParser(json)) {
+            assertThat(parser.nextToken(), equalTo(XContentParser.Token.START_OBJECT));
+            assertThat(parser.nextToken(), equalTo(XContentParser.Token.FIELD_NAME));
+            assertThat(parser.nextToken(), equalTo(XContentParser.Token.VALUE_STRING));
+            IllegalArgumentException e = expectThrows(IllegalArgumentException.class, () -> Fuzziness.parse(parser));
+            assertTrue(e.getMessage().startsWith("Invalid fuzziness value:"));
+        }
+        json = jsonBuilder().startObject().field(Fuzziness.X_FIELD_NAME, "AUTO:").endObject();
+        try (XContentParser parser = createParser(json)) {
+            assertThat(parser.nextToken(), equalTo(XContentParser.Token.START_OBJECT));
+            assertThat(parser.nextToken(), equalTo(XContentParser.Token.FIELD_NAME));
+            assertThat(parser.nextToken(), equalTo(XContentParser.Token.VALUE_STRING));
+            OpenSearchParseException e = expectThrows(OpenSearchParseException.class, () -> Fuzziness.parse(parser));
+            assertTrue(e.getMessage().startsWith("failed to find low and high distance values"));
+        }
+    }
+
     public void testAuto() {
         assertThat(Fuzziness.AUTO.asFloat(), equalTo(1f));
     }
diff --git a/server/src/test/java/org/opensearch/common/xcontent/support/XContentMapValuesTests.java b/server/src/test/java/org/opensearch/common/xcontent/support/XContentMapValuesTests.java
index 8d8ba9872ee61..0760680f0ef2a 100644
--- a/server/src/test/java/org/opensearch/common/xcontent/support/XContentMapValuesTests.java
+++ b/server/src/test/java/org/opensearch/common/xcontent/support/XContentMapValuesTests.java
@@ -224,14 +224,8 @@ public void testExtractValueWithNullValue() throws Exception {
         assertNull(XContentMapValues.extractValue("object1.missing", map, "NULL"));
 
         assertEquals("NULL", XContentMapValues.extractValue("other_field", map, "NULL"));
-        assertEquals(
-            org.opensearch.common.collect.List.of("value1", "NULL", "value2"),
-            XContentMapValues.extractValue("array", map, "NULL")
-        );
-        assertEquals(
-            org.opensearch.common.collect.List.of("NULL", "value"),
-            XContentMapValues.extractValue("object_array.field", map, "NULL")
-        );
+        assertEquals(List.of("value1", "NULL", "value2"), XContentMapValues.extractValue("array", map, "NULL"));
+        assertEquals(List.of("NULL", "value"), XContentMapValues.extractValue("object_array.field", map, "NULL"));
         assertEquals("NULL", XContentMapValues.extractValue("object1.object2.field", map, "NULL"));
     }
 
diff --git a/server/src/test/java/org/opensearch/discovery/DiscoveryModuleTests.java b/server/src/test/java/org/opensearch/discovery/DiscoveryModuleTests.java
index 5588e9c1ceba8..1be312194d336 100644
--- a/server/src/test/java/org/opensearch/discovery/DiscoveryModuleTests.java
+++ b/server/src/test/java/org/opensearch/discovery/DiscoveryModuleTests.java
@@ -218,10 +218,9 @@ public void testMultipleSeedsProviders() {
     }
 
     public void testLazyConstructionSeedsProvider() {
-        DummyHostsProviderPlugin plugin = () -> Collections.singletonMap(
-            "custom",
-            () -> { throw new AssertionError("created hosts provider which was not selected"); }
-        );
+        DummyHostsProviderPlugin plugin = () -> Collections.singletonMap("custom", () -> {
+            throw new AssertionError("created hosts provider which was not selected");
+        });
         newModule(Settings.EMPTY, Collections.singletonList(plugin));
     }
 
diff --git a/server/src/test/java/org/opensearch/discovery/InitializeExtensionRequestTests.java b/server/src/test/java/org/opensearch/discovery/InitializeExtensionRequestTests.java
new file mode 100644
index 0000000000000..97820e6197eec
--- /dev/null
+++ b/server/src/test/java/org/opensearch/discovery/InitializeExtensionRequestTests.java
@@ -0,0 +1,64 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+package org.opensearch.discovery;
+
+import org.opensearch.Version;
+import org.opensearch.cluster.node.DiscoveryNode;
+import org.opensearch.cluster.node.DiscoveryNodeRole;
+import org.opensearch.common.bytes.BytesReference;
+import org.opensearch.common.io.stream.BytesStreamInput;
+import org.opensearch.common.io.stream.BytesStreamOutput;
+import org.opensearch.common.transport.TransportAddress;
+import org.opensearch.extensions.DiscoveryExtensionNode;
+import org.opensearch.extensions.ExtensionDependency;
+import org.opensearch.test.OpenSearchTestCase;
+
+import java.net.InetAddress;
+import java.util.HashMap;
+import java.util.List;
+
+public class InitializeExtensionRequestTests extends OpenSearchTestCase {
+
+    public void testInitializeExtensionRequest() throws Exception {
+        String expectedUniqueId = "test uniqueid";
+        Version expectedVersion = Version.fromString("2.0.0");
+        ExtensionDependency expectedDependency = new ExtensionDependency(expectedUniqueId, expectedVersion);
+        DiscoveryExtensionNode expectedExtensionNode = new DiscoveryExtensionNode(
+            "firstExtension",
+            "uniqueid1",
+            new TransportAddress(InetAddress.getByName("127.0.0.0"), 9300),
+            new HashMap<>(),
+            Version.CURRENT,
+            Version.CURRENT,
+            List.of(expectedDependency)
+        );
+        DiscoveryNode expectedSourceNode = new DiscoveryNode(
+            "sourceNode",
+            "uniqueid2",
+            new TransportAddress(InetAddress.getByName("127.0.0.0"), 1000),
+            new HashMap<>(),
+            DiscoveryNodeRole.BUILT_IN_ROLES,
+            Version.CURRENT
+        );
+
+        InitializeExtensionRequest initializeExtensionRequest = new InitializeExtensionRequest(expectedSourceNode, expectedExtensionNode);
+        assertEquals(expectedExtensionNode, initializeExtensionRequest.getExtension());
+        assertEquals(expectedSourceNode, initializeExtensionRequest.getSourceNode());
+
+        try (BytesStreamOutput out = new BytesStreamOutput()) {
+            initializeExtensionRequest.writeTo(out);
+            out.flush();
+            try (BytesStreamInput in = new BytesStreamInput(BytesReference.toBytes(out.bytes()))) {
+                initializeExtensionRequest = new InitializeExtensionRequest(in);
+
+                assertEquals(expectedExtensionNode, initializeExtensionRequest.getExtension());
+                assertEquals(expectedSourceNode, initializeExtensionRequest.getSourceNode());
+            }
+        }
+    }
+}
diff --git a/server/src/test/java/org/opensearch/discovery/InitializeExtensionResponseTests.java b/server/src/test/java/org/opensearch/discovery/InitializeExtensionResponseTests.java
new file mode 100644
index 0000000000000..ea7cc96b0e2a4
--- /dev/null
+++ b/server/src/test/java/org/opensearch/discovery/InitializeExtensionResponseTests.java
@@ -0,0 +1,51 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.discovery;
+
+import org.opensearch.common.bytes.BytesReference;
+import org.opensearch.common.io.stream.BytesStreamInput;
+import org.opensearch.common.io.stream.BytesStreamOutput;
+import org.opensearch.test.OpenSearchTestCase;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+public class InitializeExtensionResponseTests extends OpenSearchTestCase {
+    public void testInitializeExtensionResponse() throws Exception {
+        String expectedName = "testsample-sdk";
+        List<String> expectedImplementedInterfaces = new ArrayList<>(Arrays.asList("Action", "Search"));
+
+        InitializeExtensionResponse initializeExtensionResponse = new InitializeExtensionResponse(
+            expectedName,
+            expectedImplementedInterfaces
+        );
+
+        assertEquals(expectedName, initializeExtensionResponse.getName());
+        List<String> implementedInterfaces = initializeExtensionResponse.getImplementedInterfaces();
+        assertEquals(expectedImplementedInterfaces.size(), implementedInterfaces.size());
+        assertTrue(implementedInterfaces.containsAll(expectedImplementedInterfaces));
+        assertTrue(expectedImplementedInterfaces.containsAll(implementedInterfaces));
+
+        try (BytesStreamOutput out = new BytesStreamOutput()) {
+            initializeExtensionResponse.writeTo(out);
+            out.flush();
+            try (BytesStreamInput in = new BytesStreamInput(BytesReference.toBytes(out.bytes()))) {
+                initializeExtensionResponse = new InitializeExtensionResponse(in);
+
+                assertEquals(expectedName, initializeExtensionResponse.getName());
+                implementedInterfaces = initializeExtensionResponse.getImplementedInterfaces();
+                assertEquals(expectedImplementedInterfaces.size(), implementedInterfaces.size());
+                assertTrue(implementedInterfaces.containsAll(expectedImplementedInterfaces));
+                assertTrue(expectedImplementedInterfaces.containsAll(implementedInterfaces));
+            }
+        }
+    }
+
+}
diff --git a/server/src/test/java/org/opensearch/env/NodeEnvironmentTests.java b/server/src/test/java/org/opensearch/env/NodeEnvironmentTests.java
index e50aaea009ba6..808d3c0a7ffea 100644
--- a/server/src/test/java/org/opensearch/env/NodeEnvironmentTests.java
+++ b/server/src/test/java/org/opensearch/env/NodeEnvironmentTests.java
@@ -591,7 +591,7 @@ public void testEnsureNoShardDataOrIndexMetadata() throws IOException {
 
     public void testSearchFileCacheConfiguration() throws IOException {
         Settings searchRoleSettings = addRoles(buildEnvSettings(Settings.EMPTY), Set.of(DiscoveryNodeRole.SEARCH_ROLE));
-        ByteSizeValue cacheSize = new ByteSizeValue(100, ByteSizeUnit.MB);
+        ByteSizeValue cacheSize = new ByteSizeValue(16, ByteSizeUnit.GB);
         Settings searchRoleSettingsWithConfig = Settings.builder()
             .put(searchRoleSettings)
             .put(Node.NODE_SEARCH_CACHE_SIZE_SETTING.getKey(), cacheSize)
diff --git a/server/src/test/java/org/opensearch/env/NodeRepurposeCommandTests.java b/server/src/test/java/org/opensearch/env/NodeRepurposeCommandTests.java
index 009ff324809b4..f172ebe7d37d9 100644
--- a/server/src/test/java/org/opensearch/env/NodeRepurposeCommandTests.java
+++ b/server/src/test/java/org/opensearch/env/NodeRepurposeCommandTests.java
@@ -46,6 +46,8 @@
 import org.opensearch.common.CheckedRunnable;
 import org.opensearch.common.settings.ClusterSettings;
 import org.opensearch.common.settings.Settings;
+import org.opensearch.common.unit.ByteSizeUnit;
+import org.opensearch.common.unit.ByteSizeValue;
 import org.opensearch.common.util.BigArrays;
 import org.opensearch.gateway.PersistedClusterStateService;
 import org.opensearch.index.Index;
@@ -57,16 +59,19 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.Arrays;
-import java.util.Collections;
-import java.util.HashSet;
+import java.util.Set;
 import java.util.stream.Stream;
 
 import static org.opensearch.env.NodeRepurposeCommand.NO_CLEANUP;
 import static org.opensearch.env.NodeRepurposeCommand.NO_DATA_TO_CLEAN_UP_FOUND;
+import static org.opensearch.env.NodeRepurposeCommand.NO_FILE_CACHE_DATA_TO_CLEAN_UP_FOUND;
 import static org.opensearch.env.NodeRepurposeCommand.NO_SHARD_DATA_TO_CLEAN_UP_FOUND;
+import static org.opensearch.node.Node.NODE_SEARCH_CACHE_SIZE_SETTING;
+import static org.opensearch.test.NodeRoles.addRoles;
 import static org.opensearch.test.NodeRoles.clusterManagerNode;
 import static org.opensearch.test.NodeRoles.nonDataNode;
 import static org.opensearch.test.NodeRoles.nonClusterManagerNode;
+import static org.opensearch.test.NodeRoles.onlyRole;
 import static org.opensearch.test.NodeRoles.removeRoles;
 import static org.hamcrest.Matchers.allOf;
 import static org.hamcrest.Matchers.containsString;
@@ -76,15 +81,35 @@ public class NodeRepurposeCommandTests extends OpenSearchTestCase {
 
     private static final Index INDEX = new Index("testIndex", "testUUID");
     private Settings dataClusterManagerSettings;
+    private Settings dataSearchClusterManagerSettings;
     private Environment environment;
     private Path[] nodePaths;
-    private Settings dataNoClusterManagerSettings;
+    private Settings dataSearchNoClusterManagerSettings;
     private Settings noDataNoClusterManagerSettings;
     private Settings noDataClusterManagerSettings;
+    private Settings searchNoDataNoClusterManagerSettings;
+    private Settings noSearchNoClusterManagerSettings;
 
     @Before
     public void createNodePaths() throws IOException {
         dataClusterManagerSettings = buildEnvSettings(Settings.EMPTY);
+        Settings defaultSearchSettings = Settings.builder()
+            .put(dataClusterManagerSettings)
+            .put(NODE_SEARCH_CACHE_SIZE_SETTING.getKey(), new ByteSizeValue(16, ByteSizeUnit.GB))
+            .build();
+
+        searchNoDataNoClusterManagerSettings = onlyRole(dataClusterManagerSettings, DiscoveryNodeRole.SEARCH_ROLE);
+        dataSearchClusterManagerSettings = addRoles(defaultSearchSettings, Set.of(DiscoveryNodeRole.SEARCH_ROLE));
+        noDataClusterManagerSettings = clusterManagerNode(nonDataNode(dataClusterManagerSettings));
+
+        dataSearchNoClusterManagerSettings = nonClusterManagerNode(dataSearchClusterManagerSettings);
+        noSearchNoClusterManagerSettings = nonClusterManagerNode(defaultSearchSettings);
+
+        noDataNoClusterManagerSettings = removeRoles(
+            dataClusterManagerSettings,
+            Set.of(DiscoveryNodeRole.DATA_ROLE, DiscoveryNodeRole.CLUSTER_MANAGER_ROLE)
+        );
+
         environment = TestEnvironment.newEnvironment(dataClusterManagerSettings);
         try (NodeEnvironment nodeEnvironment = new NodeEnvironment(dataClusterManagerSettings, environment)) {
             nodePaths = nodeEnvironment.nodeDataPaths();
@@ -102,20 +127,13 @@ public void createNodePaths() throws IOException {
                 writer.writeFullStateAndCommit(1L, ClusterState.EMPTY_STATE);
             }
         }
-        dataNoClusterManagerSettings = nonClusterManagerNode(dataClusterManagerSettings);
-        noDataNoClusterManagerSettings = removeRoles(
-            dataClusterManagerSettings,
-            Collections.unmodifiableSet(new HashSet<>(Arrays.asList(DiscoveryNodeRole.DATA_ROLE, DiscoveryNodeRole.CLUSTER_MANAGER_ROLE)))
-        );
-
-        noDataClusterManagerSettings = clusterManagerNode(nonDataNode(dataClusterManagerSettings));
     }
 
     public void testEarlyExitNoCleanup() throws Exception {
         createIndexDataFiles(dataClusterManagerSettings, randomInt(10), randomBoolean());
 
-        verifyNoQuestions(dataClusterManagerSettings, containsString(NO_CLEANUP));
-        verifyNoQuestions(dataNoClusterManagerSettings, containsString(NO_CLEANUP));
+        verifyNoQuestions(dataSearchClusterManagerSettings, containsString(NO_CLEANUP));
+        verifyNoQuestions(dataSearchNoClusterManagerSettings, containsString(NO_CLEANUP));
     }
 
     public void testNothingToCleanup() throws Exception {
@@ -138,6 +156,7 @@ public void testNothingToCleanup() throws Exception {
 
         verifyNoQuestions(noDataNoClusterManagerSettings, containsString(NO_DATA_TO_CLEAN_UP_FOUND));
         verifyNoQuestions(noDataClusterManagerSettings, containsString(NO_SHARD_DATA_TO_CLEAN_UP_FOUND));
+        verifyNoQuestions(noSearchNoClusterManagerSettings, containsString(NO_FILE_CACHE_DATA_TO_CLEAN_UP_FOUND));
 
         createIndexDataFiles(dataClusterManagerSettings, 0, randomBoolean());
 
@@ -159,7 +178,7 @@ public void testLocked() throws IOException {
         }
     }
 
-    public void testCleanupAll() throws Exception {
+    public void testCleanupDataClusterManager() throws Exception {
         int shardCount = randomIntBetween(1, 10);
         boolean verbose = randomBoolean();
         boolean hasClusterState = randomBoolean();
@@ -208,6 +227,84 @@ public void testCleanupShardData() throws Exception {
         new NodeEnvironment(noDataClusterManagerSettings, environment).close();
     }
 
+    public void testCleanupSearchNode() throws Exception {
+        int shardCount = randomIntBetween(1, 10);
+        boolean verbose = randomBoolean();
+        boolean hasClusterState = randomBoolean();
+        createIndexDataFiles(searchNoDataNoClusterManagerSettings, shardCount, hasClusterState, true);
+
+        Matcher<String> matcher = allOf(
+            containsString(NodeRepurposeCommand.shardMessage(shardCount, 1)),
+            conditionalNot(containsString("testUUID"), verbose == false),
+            conditionalNot(containsString("testIndex"), verbose == false || hasClusterState == false),
+            conditionalNot(containsString("no name for uuid: testUUID"), verbose == false || hasClusterState)
+        );
+
+        verifyUnchangedOnAbort(dataClusterManagerSettings, matcher, verbose);
+
+        // verify test setup
+        expectThrows(IllegalStateException.class, () -> new NodeEnvironment(dataClusterManagerSettings, environment).close());
+
+        verifySuccess(dataClusterManagerSettings, matcher, verbose);
+
+        // verify clean.
+        new NodeEnvironment(dataClusterManagerSettings, environment).close();
+    }
+
+    public void testCleanupSearchClusterManager() throws Exception {
+        int shardCount = randomIntBetween(1, 10);
+        boolean verbose = randomBoolean();
+        boolean hasClusterState = randomBoolean();
+        createIndexDataFiles(dataSearchClusterManagerSettings, shardCount, hasClusterState, true);
+
+        String messageText = NodeRepurposeCommand.noClusterManagerMessage(1, shardCount, 0);
+
+        Matcher<String> matcher = allOf(
+            containsString(messageText),
+            conditionalNot(containsString("testUUID"), verbose == false),
+            conditionalNot(containsString("testIndex"), verbose == false || hasClusterState == false),
+            conditionalNot(containsString("no name for uuid: testUUID"), verbose == false || hasClusterState)
+        );
+
+        verifyUnchangedOnAbort(noSearchNoClusterManagerSettings, matcher, verbose);
+
+        // verify test setup
+        expectThrows(IllegalStateException.class, () -> new NodeEnvironment(noSearchNoClusterManagerSettings, environment).close());
+
+        verifySuccess(noSearchNoClusterManagerSettings, matcher, verbose);
+
+        // verify clean.
+        new NodeEnvironment(noSearchNoClusterManagerSettings, environment).close();
+    }
+
+    public void testCleanupAll() throws Exception {
+        int shardCount = randomIntBetween(1, 10);
+        boolean verbose = randomBoolean();
+        boolean hasClusterState = randomBoolean();
+        createIndexDataFiles(dataSearchClusterManagerSettings, shardCount, hasClusterState, false);
+        createIndexDataFiles(dataSearchClusterManagerSettings, shardCount, hasClusterState, true);
+
+        // environment.dataFiles().length * shardCount will account for the local shard files
+        // + shardCount will account for the additional file cache shard files.
+        String messageText = NodeRepurposeCommand.noClusterManagerMessage(1, (environment.dataFiles().length * shardCount) + shardCount, 0);
+
+        Matcher<String> outputMatcher = allOf(
+            containsString(messageText),
+            conditionalNot(containsString("testIndex"), verbose == false || hasClusterState == false),
+            conditionalNot(containsString("no name for uuid: testUUID"), verbose == false || hasClusterState)
+        );
+
+        verifyUnchangedOnAbort(noDataNoClusterManagerSettings, outputMatcher, verbose);
+
+        // verify test setup
+        expectThrows(IllegalStateException.class, () -> new NodeEnvironment(noDataNoClusterManagerSettings, environment).close());
+
+        verifySuccess(noDataNoClusterManagerSettings, outputMatcher, verbose);
+
+        // verify cleaned.
+        new NodeEnvironment(noDataNoClusterManagerSettings, environment).close();
+    }
+
     static void verifySuccess(Settings settings, Matcher<String> outputMatcher, boolean verbose) throws Exception {
         withTerminal(verbose, outputMatcher, terminal -> {
             terminal.addTextInput(randomFrom("y", "Y"));
@@ -256,6 +353,10 @@ private static void executeRepurposeCommand(MockTerminal terminal, Settings sett
     }
 
     private void createIndexDataFiles(Settings settings, int shardCount, boolean writeClusterState) throws IOException {
+        createIndexDataFiles(settings, shardCount, writeClusterState, false);
+    }
+
+    private void createIndexDataFiles(Settings settings, int shardCount, boolean writeClusterState, boolean cacheMode) throws IOException {
         int shardDataDirNumber = randomInt(10);
         Environment environment = TestEnvironment.newEnvironment(settings);
         try (NodeEnvironment env = new NodeEnvironment(settings, environment)) {
@@ -287,12 +388,23 @@ private void createIndexDataFiles(Settings settings, int shardCount, boolean wri
                     );
                 }
             }
-            for (Path path : env.indexPaths(INDEX)) {
+
+            if (cacheMode) {
+                Path cachePath = env.fileCacheNodePath().fileCachePath;
+                cachePath = cachePath.resolve(String.valueOf(env.getNodeLockId())).resolve(INDEX.getUUID());
                 for (int i = 0; i < shardCount; ++i) {
-                    Files.createDirectories(path.resolve(Integer.toString(shardDataDirNumber)));
+                    Files.createDirectories(cachePath.resolve(Integer.toString(shardDataDirNumber)));
                     shardDataDirNumber += randomIntBetween(1, 10);
                 }
+            } else {
+                for (Path path : env.indexPaths(INDEX)) {
+                    for (int i = 0; i < shardCount; ++i) {
+                        Files.createDirectories(path.resolve(Integer.toString(shardDataDirNumber)));
+                        shardDataDirNumber += randomIntBetween(1, 10);
+                    }
+                }
             }
+
         }
     }
 
diff --git a/server/src/test/java/org/opensearch/extensions/RegisterTransportActionsRequestTests.java b/server/src/test/java/org/opensearch/extensions/RegisterTransportActionsRequestTests.java
index eb59c80ac6461..27f1597e5779f 100644
--- a/server/src/test/java/org/opensearch/extensions/RegisterTransportActionsRequestTests.java
+++ b/server/src/test/java/org/opensearch/extensions/RegisterTransportActionsRequestTests.java
@@ -9,20 +9,19 @@
 package org.opensearch.extensions;
 
 import org.junit.Before;
-import org.opensearch.action.admin.indices.create.AutoCreateAction.TransportAction;
-import org.opensearch.common.collect.Map;
 import org.opensearch.common.io.stream.BytesStreamOutput;
 import org.opensearch.common.io.stream.StreamInput;
 import org.opensearch.test.OpenSearchTestCase;
 
 import java.io.IOException;
+import java.util.Set;
 
 public class RegisterTransportActionsRequestTests extends OpenSearchTestCase {
     private RegisterTransportActionsRequest originalRequest;
 
     @Before
     public void setup() {
-        this.originalRequest = new RegisterTransportActionsRequest("extension-uniqueId", Map.of("testAction", TransportAction.class));
+        this.originalRequest = new RegisterTransportActionsRequest("extension-uniqueId", Set.of("testAction"));
     }
 
     public void testRegisterTransportActionsRequest() throws IOException {
@@ -31,16 +30,12 @@ public void testRegisterTransportActionsRequest() throws IOException {
         StreamInput input = output.bytes().streamInput();
         RegisterTransportActionsRequest parsedRequest = new RegisterTransportActionsRequest(input);
         assertEquals(parsedRequest.getTransportActions(), originalRequest.getTransportActions());
-        assertEquals(parsedRequest.getTransportActions().get("testAction"), originalRequest.getTransportActions().get("testAction"));
         assertEquals(parsedRequest.getTransportActions().size(), originalRequest.getTransportActions().size());
         assertEquals(parsedRequest.hashCode(), originalRequest.hashCode());
         assertTrue(originalRequest.equals(parsedRequest));
     }
 
     public void testToString() {
-        assertEquals(
-            originalRequest.toString(),
-            "TransportActionsRequest{uniqueId=extension-uniqueId, actions={testAction=class org.opensearch.action.admin.indices.create.AutoCreateAction$TransportAction}}"
-        );
+        assertEquals(originalRequest.toString(), "TransportActionsRequest{uniqueId=extension-uniqueId, actions=[testAction]}");
     }
 }
diff --git a/server/src/test/java/org/opensearch/extensions/action/ExtensionTransportActionsHandlerTests.java b/server/src/test/java/org/opensearch/extensions/action/ExtensionTransportActionsHandlerTests.java
index 6f29cd780aaa8..2d0821a0fb7dd 100644
--- a/server/src/test/java/org/opensearch/extensions/action/ExtensionTransportActionsHandlerTests.java
+++ b/server/src/test/java/org/opensearch/extensions/action/ExtensionTransportActionsHandlerTests.java
@@ -11,7 +11,6 @@
 import org.junit.After;
 import org.junit.Before;
 import org.opensearch.Version;
-import org.opensearch.action.admin.indices.create.AutoCreateAction.TransportAction;
 import org.opensearch.client.node.NodeClient;
 import org.opensearch.cluster.node.DiscoveryNode;
 import org.opensearch.common.io.stream.NamedWriteableRegistry;
@@ -39,6 +38,7 @@
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.Set;
 import java.util.concurrent.TimeUnit;
 
 import static java.util.Collections.emptyMap;
@@ -118,7 +118,7 @@ public void testRegisterAction() {
 
     public void testRegisterTransportActionsRequest() {
         String action = "test-action";
-        RegisterTransportActionsRequest request = new RegisterTransportActionsRequest("uniqueid1", Map.of(action, TransportAction.class));
+        RegisterTransportActionsRequest request = new RegisterTransportActionsRequest("uniqueid1", Set.of(action));
         AcknowledgedResponse response = (AcknowledgedResponse) extensionTransportActionsHandler.handleRegisterTransportActionsRequest(
             request
         );
@@ -150,10 +150,7 @@ public void testSendTransportRequestToExtension() throws InterruptedException {
         );
 
         // Register Action
-        RegisterTransportActionsRequest registerRequest = new RegisterTransportActionsRequest(
-            "uniqueid1",
-            Map.of(action, TransportAction.class)
-        );
+        RegisterTransportActionsRequest registerRequest = new RegisterTransportActionsRequest("uniqueid1", Set.of(action));
         AcknowledgedResponse response = (AcknowledgedResponse) extensionTransportActionsHandler.handleRegisterTransportActionsRequest(
             registerRequest
         );
diff --git a/server/src/test/java/org/opensearch/gateway/GatewayMetaStateTests.java b/server/src/test/java/org/opensearch/gateway/GatewayMetaStateTests.java
index d1c177ae5964c..8358dc84b2e0e 100644
--- a/server/src/test/java/org/opensearch/gateway/GatewayMetaStateTests.java
+++ b/server/src/test/java/org/opensearch/gateway/GatewayMetaStateTests.java
@@ -114,9 +114,9 @@ public void testCustomMetadataNoChange() {
 
     public void testIndexTemplateValidation() {
         Metadata metadata = randomMetadata();
-        MetadataUpgrader metadataUpgrader = new MetadataUpgrader(
-            Collections.singletonList(customs -> { throw new IllegalStateException("template is incompatible"); })
-        );
+        MetadataUpgrader metadataUpgrader = new MetadataUpgrader(Collections.singletonList(customs -> {
+            throw new IllegalStateException("template is incompatible");
+        }));
         String message = expectThrows(
             IllegalStateException.class,
             () -> GatewayMetaState.upgradeMetadata(metadata, new MockMetadataIndexUpgradeService(false), metadataUpgrader)
diff --git a/server/src/test/java/org/opensearch/gateway/PrimaryShardAllocatorTests.java b/server/src/test/java/org/opensearch/gateway/PrimaryShardAllocatorTests.java
index 3c39ec9f03b2a..9a1f3618fcd8a 100644
--- a/server/src/test/java/org/opensearch/gateway/PrimaryShardAllocatorTests.java
+++ b/server/src/test/java/org/opensearch/gateway/PrimaryShardAllocatorTests.java
@@ -220,9 +220,9 @@ public void testPreferReplicaWithHighestPrimaryTerm() {
             allocId2,
             allocId3
         );
-        testAllocator.addData(node1, allocId1, false, new ReplicationCheckpoint(shardId, 20, 10, 101, 1));
-        testAllocator.addData(node2, allocId2, false, new ReplicationCheckpoint(shardId, 22, 10, 120, 2));
-        testAllocator.addData(node3, allocId3, false, new ReplicationCheckpoint(shardId, 20, 10, 120, 2));
+        testAllocator.addData(node1, allocId1, false, new ReplicationCheckpoint(shardId, 20, 101, 1));
+        testAllocator.addData(node2, allocId2, false, new ReplicationCheckpoint(shardId, 22, 120, 2));
+        testAllocator.addData(node3, allocId3, false, new ReplicationCheckpoint(shardId, 20, 120, 2));
         allocateAllUnassigned(allocation);
         assertThat(allocation.routingNodesChanged(), equalTo(true));
         assertThat(allocation.routingNodes().unassigned().ignored().isEmpty(), equalTo(true));
@@ -253,9 +253,9 @@ public void testPreferReplicaWithNullReplicationCheckpoint() {
             allocId2,
             allocId3
         );
-        testAllocator.addData(node1, allocId1, false, new ReplicationCheckpoint(shardId, 20, 10, 101, 1));
+        testAllocator.addData(node1, allocId1, false, new ReplicationCheckpoint(shardId, 20, 101, 1));
         testAllocator.addData(node2, allocId2, false);
-        testAllocator.addData(node3, allocId3, false, new ReplicationCheckpoint(shardId, 40, 10, 120, 2));
+        testAllocator.addData(node3, allocId3, false, new ReplicationCheckpoint(shardId, 40, 120, 2));
         allocateAllUnassigned(allocation);
         assertThat(allocation.routingNodesChanged(), equalTo(true));
         assertThat(allocation.routingNodes().unassigned().ignored().isEmpty(), equalTo(true));
@@ -319,9 +319,9 @@ public void testPreferReplicaWithHighestSegmentInfoVersion() {
             allocId2,
             allocId3
         );
-        testAllocator.addData(node1, allocId1, false, new ReplicationCheckpoint(shardId, 10, 10, 101, 1));
-        testAllocator.addData(node2, allocId2, false, new ReplicationCheckpoint(shardId, 20, 10, 120, 3));
-        testAllocator.addData(node3, allocId3, false, new ReplicationCheckpoint(shardId, 20, 10, 120, 2));
+        testAllocator.addData(node1, allocId1, false, new ReplicationCheckpoint(shardId, 10, 101, 1));
+        testAllocator.addData(node2, allocId2, false, new ReplicationCheckpoint(shardId, 20, 120, 3));
+        testAllocator.addData(node3, allocId3, false, new ReplicationCheckpoint(shardId, 20, 120, 2));
         allocateAllUnassigned(allocation);
         assertThat(allocation.routingNodesChanged(), equalTo(true));
         assertThat(allocation.routingNodes().unassigned().ignored().isEmpty(), equalTo(true));
@@ -351,9 +351,9 @@ public void testOutOfSyncHighestRepCheckpointIsIgnored() {
             allocId1,
             allocId3
         );
-        testAllocator.addData(node1, allocId1, false, new ReplicationCheckpoint(shardId, 10, 10, 101, 1));
-        testAllocator.addData(node2, allocId2, false, new ReplicationCheckpoint(shardId, 20, 10, 120, 2));
-        testAllocator.addData(node3, allocId3, false, new ReplicationCheckpoint(shardId, 15, 10, 120, 2));
+        testAllocator.addData(node1, allocId1, false, new ReplicationCheckpoint(shardId, 10, 101, 1));
+        testAllocator.addData(node2, allocId2, false, new ReplicationCheckpoint(shardId, 20, 120, 2));
+        testAllocator.addData(node3, allocId3, false, new ReplicationCheckpoint(shardId, 15, 120, 2));
         allocateAllUnassigned(allocation);
         assertThat(allocation.routingNodesChanged(), equalTo(true));
         assertThat(allocation.routingNodes().unassigned().ignored().isEmpty(), equalTo(true));
@@ -384,9 +384,9 @@ public void testPreferAllocatingPreviousPrimaryWithLowerRepCheckpoint() {
             allocId2,
             allocId3
         );
-        testAllocator.addData(node1, allocId1, true, new ReplicationCheckpoint(shardId, 10, 10, 101, 1));
-        testAllocator.addData(node2, allocId2, false, new ReplicationCheckpoint(shardId, 20, 10, 120, 2));
-        testAllocator.addData(node3, allocId3, false, new ReplicationCheckpoint(shardId, 15, 10, 120, 2));
+        testAllocator.addData(node1, allocId1, true, new ReplicationCheckpoint(shardId, 10, 101, 1));
+        testAllocator.addData(node2, allocId2, false, new ReplicationCheckpoint(shardId, 20, 120, 2));
+        testAllocator.addData(node3, allocId3, false, new ReplicationCheckpoint(shardId, 15, 120, 2));
         allocateAllUnassigned(allocation);
         assertThat(allocation.routingNodesChanged(), equalTo(true));
         assertThat(allocation.routingNodes().unassigned().ignored().isEmpty(), equalTo(true));
diff --git a/server/src/test/java/org/opensearch/index/IndexSettingsTests.java b/server/src/test/java/org/opensearch/index/IndexSettingsTests.java
index b266335f3d572..663e9e5007a8f 100644
--- a/server/src/test/java/org/opensearch/index/IndexSettingsTests.java
+++ b/server/src/test/java/org/opensearch/index/IndexSettingsTests.java
@@ -100,8 +100,9 @@ public void testSettingsUpdateValidator() {
         Setting<Integer> integerSetting = Setting.intSetting("index.test.setting.int", -1, Property.Dynamic, Property.IndexScope);
         IndexMetadata metadata = newIndexMeta("index", theSettings);
         IndexSettings settings = newIndexSettings(newIndexMeta("index", theSettings), Settings.EMPTY, integerSetting);
-        settings.getScopedSettings()
-            .addSettingsUpdateConsumer(integerSetting, integer::set, (i) -> { if (i == 42) throw new AssertionError("boom"); });
+        settings.getScopedSettings().addSettingsUpdateConsumer(integerSetting, integer::set, (i) -> {
+            if (i == 42) throw new AssertionError("boom");
+        });
 
         assertEquals(version, settings.getIndexVersionCreated());
         assertEquals("0xdeadbeef", settings.getUUID());
@@ -654,15 +655,15 @@ public void testArchivedSettingsValidation() {
     }
 
     public void testArchiveBrokenIndexSettings() {
-        Settings settings = IndexScopedSettings.DEFAULT_SCOPED_SETTINGS.archiveUnknownOrInvalidSettings(
-            Settings.EMPTY,
-            e -> { assert false : "should not have been invoked, no unknown settings"; },
-            (e, ex) -> { assert false : "should not have been invoked, no invalid settings"; }
-        );
+        Settings settings = IndexScopedSettings.DEFAULT_SCOPED_SETTINGS.archiveUnknownOrInvalidSettings(Settings.EMPTY, e -> {
+            assert false : "should not have been invoked, no unknown settings";
+        }, (e, ex) -> { assert false : "should not have been invoked, no invalid settings"; });
         assertSame(settings, Settings.EMPTY);
         settings = IndexScopedSettings.DEFAULT_SCOPED_SETTINGS.archiveUnknownOrInvalidSettings(
             Settings.builder().put("index.refresh_interval", "-200").build(),
-            e -> { assert false : "should not have been invoked, no invalid settings"; },
+            e -> {
+                assert false : "should not have been invoked, no invalid settings";
+            },
             (e, ex) -> {
                 assertThat(e.getKey(), equalTo("index.refresh_interval"));
                 assertThat(e.getValue(), equalTo("-200"));
@@ -673,11 +674,9 @@ public void testArchiveBrokenIndexSettings() {
         assertNull(settings.get("index.refresh_interval"));
 
         Settings prevSettings = settings; // no double archive
-        settings = IndexScopedSettings.DEFAULT_SCOPED_SETTINGS.archiveUnknownOrInvalidSettings(
-            prevSettings,
-            e -> { assert false : "should not have been invoked, no unknown settings"; },
-            (e, ex) -> { assert false : "should not have been invoked, no invalid settings"; }
-        );
+        settings = IndexScopedSettings.DEFAULT_SCOPED_SETTINGS.archiveUnknownOrInvalidSettings(prevSettings, e -> {
+            assert false : "should not have been invoked, no unknown settings";
+        }, (e, ex) -> { assert false : "should not have been invoked, no invalid settings"; });
         assertSame(prevSettings, settings);
 
         settings = IndexScopedSettings.DEFAULT_SCOPED_SETTINGS.archiveUnknownOrInvalidSettings(
diff --git a/server/src/test/java/org/opensearch/index/SegmentReplicationPressureServiceTests.java b/server/src/test/java/org/opensearch/index/SegmentReplicationPressureServiceTests.java
new file mode 100644
index 0000000000000..a050a4c2243db
--- /dev/null
+++ b/server/src/test/java/org/opensearch/index/SegmentReplicationPressureServiceTests.java
@@ -0,0 +1,207 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.index;
+
+import org.mockito.stubbing.Answer;
+import org.opensearch.cluster.metadata.IndexMetadata;
+import org.opensearch.cluster.service.ClusterService;
+import org.opensearch.common.settings.ClusterSettings;
+import org.opensearch.common.settings.Settings;
+import org.opensearch.common.unit.TimeValue;
+import org.opensearch.common.util.concurrent.OpenSearchRejectedExecutionException;
+import org.opensearch.index.engine.NRTReplicationEngineFactory;
+import org.opensearch.index.replication.OpenSearchIndexLevelReplicationTestCase;
+import org.opensearch.index.shard.IndexShard;
+import org.opensearch.index.shard.ShardId;
+import org.opensearch.indices.IndicesService;
+import org.opensearch.indices.replication.common.ReplicationType;
+
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.TimeUnit;
+
+import static java.util.Arrays.asList;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+import static org.opensearch.index.SegmentReplicationPressureService.MAX_REPLICATION_TIME_SETTING;
+import static org.opensearch.index.SegmentReplicationPressureService.SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED;
+
+public class SegmentReplicationPressureServiceTests extends OpenSearchIndexLevelReplicationTestCase {
+
+    private static final Settings settings = Settings.builder()
+        .put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT)
+        .put(SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED.getKey(), true)
+        .put(MAX_REPLICATION_TIME_SETTING.getKey(), TimeValue.timeValueSeconds(5))
+        .build();
+
+    public void testIsSegrepLimitBreached() throws Exception {
+        try (ReplicationGroup shards = createGroup(1, settings, new NRTReplicationEngineFactory())) {
+            shards.startAll();
+            final IndexShard primaryShard = shards.getPrimary();
+            SegmentReplicationPressureService service = buildPressureService(settings, primaryShard);
+
+            indexInBatches(5, shards, primaryShard);
+
+            SegmentReplicationStats segmentReplicationStats = service.nodeStats();
+            Map<ShardId, SegmentReplicationPerGroupStats> shardStats = segmentReplicationStats.getShardStats();
+            assertEquals(1, shardStats.size());
+            SegmentReplicationPerGroupStats groupStats = shardStats.get(primaryShard.shardId());
+            assertEquals(0, groupStats.getRejectedRequestCount());
+            Set<SegmentReplicationShardStats> replicas = groupStats.getReplicaStats();
+            assertEquals(1, replicas.size());
+            SegmentReplicationShardStats replicaStats = replicas.stream().findFirst().get();
+            assertEquals(5, replicaStats.getCheckpointsBehindCount());
+
+            assertBusy(
+                () -> expectThrows(OpenSearchRejectedExecutionException.class, () -> service.isSegrepLimitBreached(primaryShard.shardId())),
+                30,
+                TimeUnit.SECONDS
+            );
+            assertBusy(
+                () -> expectThrows(OpenSearchRejectedExecutionException.class, () -> service.isSegrepLimitBreached(primaryShard.shardId())),
+                30,
+                TimeUnit.SECONDS
+            );
+
+            // let shard catch up
+            replicateSegments(primaryShard, shards.getReplicas());
+
+            segmentReplicationStats = service.nodeStats();
+            shardStats = segmentReplicationStats.getShardStats();
+            assertEquals(1, shardStats.size());
+            groupStats = shardStats.get(primaryShard.shardId());
+            assertEquals(2, groupStats.getRejectedRequestCount());
+            replicas = groupStats.getReplicaStats();
+            assertEquals(1, replicas.size());
+            replicaStats = replicas.stream().findFirst().get();
+            assertEquals(0, replicaStats.getCheckpointsBehindCount());
+
+            service.isSegrepLimitBreached(primaryShard.shardId());
+        }
+    }
+
+    public void testIsSegrepLimitBreached_onlyCheckpointLimitBreached() throws Exception {
+        final Settings settings = Settings.builder()
+            .put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT)
+            .put(SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED.getKey(), true)
+            .build();
+
+        try (ReplicationGroup shards = createGroup(1, settings, new NRTReplicationEngineFactory())) {
+            shards.startAll();
+            final IndexShard primaryShard = shards.getPrimary();
+            SegmentReplicationPressureService service = buildPressureService(settings, primaryShard);
+
+            indexInBatches(5, shards, primaryShard);
+
+            Set<SegmentReplicationShardStats> replicationStats = primaryShard.getReplicationStats();
+            assertEquals(1, replicationStats.size());
+            SegmentReplicationShardStats shardStats = replicationStats.stream().findFirst().get();
+            assertEquals(5, shardStats.getCheckpointsBehindCount());
+
+            service.isSegrepLimitBreached(primaryShard.shardId());
+
+            replicateSegments(primaryShard, shards.getReplicas());
+            service.isSegrepLimitBreached(primaryShard.shardId());
+            final SegmentReplicationStats segmentReplicationStats = service.nodeStats();
+            assertEquals(0, segmentReplicationStats.getShardStats().get(primaryShard.shardId()).getRejectedRequestCount());
+        }
+    }
+
+    public void testIsSegrepLimitBreached_onlyTimeLimitBreached() throws Exception {
+        final Settings settings = Settings.builder()
+            .put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT)
+            .put(SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED.getKey(), true)
+            .build();
+
+        try (ReplicationGroup shards = createGroup(1, settings, new NRTReplicationEngineFactory())) {
+            shards.startAll();
+            final IndexShard primaryShard = shards.getPrimary();
+            final SegmentReplicationPressureService service = buildPressureService(settings, primaryShard);
+
+            indexInBatches(1, shards, primaryShard);
+
+            assertBusy(() -> {
+                Set<SegmentReplicationShardStats> replicationStats = primaryShard.getReplicationStats();
+                assertEquals(1, replicationStats.size());
+                SegmentReplicationShardStats shardStats = replicationStats.stream().findFirst().get();
+                assertTrue(shardStats.getCurrentReplicationTimeMillis() > TimeValue.timeValueSeconds(5).millis());
+            });
+
+            service.isSegrepLimitBreached(primaryShard.shardId());
+            replicateSegments(primaryShard, shards.getReplicas());
+            service.isSegrepLimitBreached(primaryShard.shardId());
+            final SegmentReplicationStats segmentReplicationStats = service.nodeStats();
+            assertEquals(0, segmentReplicationStats.getShardStats().get(primaryShard.shardId()).getRejectedRequestCount());
+        }
+    }
+
+    public void testIsSegrepLimitBreached_underStaleNodeLimit() throws Exception {
+        try (ReplicationGroup shards = createGroup(3, settings, new NRTReplicationEngineFactory())) {
+            shards.startAll();
+            final IndexShard primaryShard = shards.getPrimary();
+            indexInBatches(5, shards, primaryShard);
+            SegmentReplicationPressureService service = buildPressureService(settings, primaryShard);
+
+            assertBusy(() -> {
+                Set<SegmentReplicationShardStats> replicationStats = primaryShard.getReplicationStats();
+                assertEquals(3, replicationStats.size());
+                SegmentReplicationShardStats shardStats = replicationStats.stream().findFirst().get();
+                assertTrue(shardStats.getCurrentReplicationTimeMillis() > TimeValue.timeValueSeconds(5).millis());
+            });
+
+            expectThrows(OpenSearchRejectedExecutionException.class, () -> service.isSegrepLimitBreached(primaryShard.shardId()));
+
+            SegmentReplicationStats segmentReplicationStats = service.nodeStats();
+            assertEquals(1, segmentReplicationStats.getShardStats().get(primaryShard.shardId()).getRejectedRequestCount());
+
+            // update one replica. 2/3 stale.
+            final List<IndexShard> replicas = shards.getReplicas();
+            replicateSegments(primaryShard, asList(replicas.get(0)));
+
+            expectThrows(OpenSearchRejectedExecutionException.class, () -> service.isSegrepLimitBreached(primaryShard.shardId()));
+
+            segmentReplicationStats = service.nodeStats();
+            assertEquals(2, segmentReplicationStats.getShardStats().get(primaryShard.shardId()).getRejectedRequestCount());
+
+            // update second replica - 1/3 stale - should not throw.
+            replicateSegments(primaryShard, asList(replicas.get(1)));
+            service.isSegrepLimitBreached(primaryShard.shardId());
+
+            // catch up all.
+            replicateSegments(primaryShard, shards.getReplicas());
+            service.isSegrepLimitBreached(primaryShard.shardId());
+        }
+    }
+
+    private int indexInBatches(int count, ReplicationGroup shards, IndexShard primaryShard) throws Exception {
+        int totalDocs = 0;
+        for (int i = 0; i < count; i++) {
+            int numDocs = randomIntBetween(100, 200);
+            totalDocs += numDocs;
+            shards.indexDocs(numDocs);
+            primaryShard.refresh("Test");
+        }
+        return totalDocs;
+    }
+
+    private SegmentReplicationPressureService buildPressureService(Settings settings, IndexShard primaryShard) {
+        IndicesService indicesService = mock(IndicesService.class);
+        IndexService indexService = mock(IndexService.class);
+        when(indicesService.iterator()).thenAnswer((Answer<Iterator<IndexService>>) invocation -> List.of(indexService).iterator());
+        when(indexService.iterator()).thenAnswer((Answer<Iterator<IndexShard>>) invocation -> List.of(primaryShard).iterator());
+        when(indicesService.indexService(primaryShard.shardId().getIndex())).thenReturn(indexService);
+        when(indexService.getShard(primaryShard.shardId().id())).thenReturn(primaryShard);
+        ClusterService clusterService = mock(ClusterService.class);
+        when(clusterService.getClusterSettings()).thenReturn(new ClusterSettings(settings, ClusterSettings.BUILT_IN_CLUSTER_SETTINGS));
+
+        return new SegmentReplicationPressureService(settings, clusterService, indicesService);
+    }
+}
diff --git a/server/src/test/java/org/opensearch/index/analysis/AnalysisRegistryTests.java b/server/src/test/java/org/opensearch/index/analysis/AnalysisRegistryTests.java
index cbc189be491cd..739e26ed3d677 100644
--- a/server/src/test/java/org/opensearch/index/analysis/AnalysisRegistryTests.java
+++ b/server/src/test/java/org/opensearch/index/analysis/AnalysisRegistryTests.java
@@ -475,13 +475,10 @@ public Map<String, AnalysisProvider<TokenFilterFactory>> getTokenFilters() {
             .build();
         IndexSettings exceptionSettings = IndexSettingsModule.newIndexSettings("index", indexSettings);
 
-        IllegalArgumentException e = expectThrows(
-            IllegalArgumentException.class,
-            () -> {
-                new AnalysisModule(TestEnvironment.newEnvironment(settings), singletonList(plugin)).getAnalysisRegistry()
-                    .build(exceptionSettings);
-            }
-        );
+        IllegalArgumentException e = expectThrows(IllegalArgumentException.class, () -> {
+            new AnalysisModule(TestEnvironment.newEnvironment(settings), singletonList(plugin)).getAnalysisRegistry()
+                .build(exceptionSettings);
+        });
         assertEquals("Cannot use token filter [exception]", e.getMessage());
 
     }
diff --git a/server/src/test/java/org/opensearch/index/analysis/AnalysisTests.java b/server/src/test/java/org/opensearch/index/analysis/AnalysisTests.java
index 0446ac78d4efc..d4b825ce09e92 100644
--- a/server/src/test/java/org/opensearch/index/analysis/AnalysisTests.java
+++ b/server/src/test/java/org/opensearch/index/analysis/AnalysisTests.java
@@ -124,15 +124,9 @@ public void testParseWordListError() throws IOException {
             writer.write('\n');
         }
         Environment env = TestEnvironment.newEnvironment(nodeSettings);
-        RuntimeException ex = expectThrows(
-            RuntimeException.class,
-            () -> Analysis.parseWordList(
-                env,
-                nodeSettings,
-                "foo.bar",
-                s -> { throw new RuntimeException("Error while parsing rule = " + s); }
-            )
-        );
+        RuntimeException ex = expectThrows(RuntimeException.class, () -> Analysis.parseWordList(env, nodeSettings, "foo.bar", s -> {
+            throw new RuntimeException("Error while parsing rule = " + s);
+        }));
         assertEquals("Line [1]: Error while parsing rule = abcd", ex.getMessage());
     }
 
@@ -146,15 +140,9 @@ public void testParseWordListOutsideConfigDirError() throws IOException {
         }
         Settings nodeSettings = Settings.builder().put("foo.bar_path", dict).put(Environment.PATH_HOME_SETTING.getKey(), home).build();
         Environment env = TestEnvironment.newEnvironment(nodeSettings);
-        RuntimeException ex = expectThrows(
-            RuntimeException.class,
-            () -> Analysis.parseWordList(
-                env,
-                nodeSettings,
-                "foo.bar",
-                s -> { throw new RuntimeException("Error while parsing rule = " + s); }
-            )
-        );
+        RuntimeException ex = expectThrows(RuntimeException.class, () -> Analysis.parseWordList(env, nodeSettings, "foo.bar", s -> {
+            throw new RuntimeException("Error while parsing rule = " + s);
+        }));
         assertEquals("Line [1]: Invalid rule", ex.getMessage());
     }
 }
diff --git a/server/src/test/java/org/opensearch/index/engine/CompletionStatsCacheTests.java b/server/src/test/java/org/opensearch/index/engine/CompletionStatsCacheTests.java
index d960fa910fde6..74ce2d5bba186 100644
--- a/server/src/test/java/org/opensearch/index/engine/CompletionStatsCacheTests.java
+++ b/server/src/test/java/org/opensearch/index/engine/CompletionStatsCacheTests.java
@@ -59,9 +59,9 @@ public class CompletionStatsCacheTests extends OpenSearchTestCase {
 
     public void testExceptionsAreNotCached() {
         final AtomicInteger openCount = new AtomicInteger();
-        final CompletionStatsCache completionStatsCache = new CompletionStatsCache(
-            () -> { throw new OpenSearchException("simulated " + openCount.incrementAndGet()); }
-        );
+        final CompletionStatsCache completionStatsCache = new CompletionStatsCache(() -> {
+            throw new OpenSearchException("simulated " + openCount.incrementAndGet());
+        });
 
         assertThat(expectThrows(OpenSearchException.class, completionStatsCache::get).getMessage(), equalTo("simulated 1"));
         assertThat(expectThrows(OpenSearchException.class, completionStatsCache::get).getMessage(), equalTo("simulated 2"));
diff --git a/server/src/test/java/org/opensearch/index/engine/NRTReplicationEngineTests.java b/server/src/test/java/org/opensearch/index/engine/NRTReplicationEngineTests.java
index 26a73c4ea460c..d0d63dc96a86a 100644
--- a/server/src/test/java/org/opensearch/index/engine/NRTReplicationEngineTests.java
+++ b/server/src/test/java/org/opensearch/index/engine/NRTReplicationEngineTests.java
@@ -11,9 +11,11 @@
 import org.apache.lucene.index.IndexCommit;
 import org.apache.lucene.index.NoMergePolicy;
 import org.apache.lucene.index.SegmentInfos;
+import org.apache.lucene.search.ReferenceManager;
 import org.opensearch.cluster.metadata.IndexMetadata;
 import org.opensearch.common.concurrent.GatedCloseable;
 import org.opensearch.common.lucene.Lucene;
+import org.opensearch.common.lucene.index.OpenSearchDirectoryReader;
 import org.opensearch.common.settings.Settings;
 import org.opensearch.index.IndexSettings;
 import org.opensearch.index.seqno.LocalCheckpointTracker;
@@ -120,7 +122,7 @@ public void testUpdateSegments_replicaReceivesSISWithHigherGen() throws IOExcept
             // flush the primary engine - we don't need any segments, just force a new commit point.
             engine.flush(true, true);
             assertEquals(3, engine.getLatestSegmentInfos().getGeneration());
-            nrtEngine.updateSegments(engine.getLatestSegmentInfos(), engine.getProcessedLocalCheckpoint());
+            nrtEngine.updateSegments(engine.getLatestSegmentInfos());
             assertEquals(3, nrtEngine.getLastCommittedSegmentInfos().getGeneration());
             assertEquals(3, nrtEngine.getLatestSegmentInfos().getGeneration());
         }
@@ -144,7 +146,7 @@ public void testUpdateSegments_replicaReceivesSISWithLowerGen() throws IOExcepti
             // update the replica with segments_2 from the primary.
             final SegmentInfos primaryInfos = engine.getLatestSegmentInfos();
             assertEquals(2, primaryInfos.getGeneration());
-            nrtEngine.updateSegments(primaryInfos, engine.getProcessedLocalCheckpoint());
+            nrtEngine.updateSegments(primaryInfos);
             assertEquals(4, nrtEngine.getLastCommittedSegmentInfos().getGeneration());
             assertEquals(4, nrtEngine.getLatestSegmentInfos().getGeneration());
             assertEquals(primaryInfos.getVersion(), nrtEngine.getLatestSegmentInfos().getVersion());
@@ -172,13 +174,35 @@ public void testUpdateSegments_replicaCommitsFirstReceivedInfos() throws IOExcep
             // update replica with the latest primary infos, it will be the same gen, segments_2, ensure it is also committed.
             final SegmentInfos primaryInfos = engine.getLatestSegmentInfos();
             assertEquals(2, primaryInfos.getGeneration());
-            nrtEngine.updateSegments(primaryInfos, engine.getProcessedLocalCheckpoint());
+            nrtEngine.updateSegments(primaryInfos);
             final SegmentInfos lastCommittedSegmentInfos = nrtEngine.getLastCommittedSegmentInfos();
             assertEquals(primaryInfos.getVersion(), nrtEngine.getLatestSegmentInfos().getVersion());
             assertEquals(primaryInfos.getVersion(), lastCommittedSegmentInfos.getVersion());
         }
     }
 
+    public void testRefreshOnNRTEngine() throws IOException {
+        final AtomicLong globalCheckpoint = new AtomicLong(SequenceNumbers.NO_OPS_PERFORMED);
+
+        try (
+            final Store nrtEngineStore = createStore(INDEX_SETTINGS, newDirectory());
+            final NRTReplicationEngine nrtEngine = buildNrtReplicaEngine(globalCheckpoint, nrtEngineStore)
+        ) {
+            assertEquals(2, nrtEngine.getLastCommittedSegmentInfos().getGeneration());
+            assertEquals(2, nrtEngine.getLatestSegmentInfos().getGeneration());
+
+            ReferenceManager<OpenSearchDirectoryReader> referenceManager = nrtEngine.getReferenceManager(Engine.SearcherScope.EXTERNAL);
+            OpenSearchDirectoryReader readerBeforeRefresh = referenceManager.acquire();
+
+            nrtEngine.refresh("test refresh");
+            OpenSearchDirectoryReader readerAfterRefresh = referenceManager.acquire();
+
+            // Verify both readers before and after refresh are same and no change in segments
+            assertSame(readerBeforeRefresh, readerAfterRefresh);
+
+        }
+    }
+
     public void testTrimTranslogOps() throws Exception {
         final AtomicLong globalCheckpoint = new AtomicLong(SequenceNumbers.NO_OPS_PERFORMED);
 
diff --git a/server/src/test/java/org/opensearch/index/fielddata/IndexFieldDataServiceTests.java b/server/src/test/java/org/opensearch/index/fielddata/IndexFieldDataServiceTests.java
index d6fd079ac59e8..94d74c21bc977 100644
--- a/server/src/test/java/org/opensearch/index/fielddata/IndexFieldDataServiceTests.java
+++ b/server/src/test/java/org/opensearch/index/fielddata/IndexFieldDataServiceTests.java
@@ -327,10 +327,9 @@ private void doTestRequireDocValues(MappedFieldType ft) {
             if (ft.hasDocValues()) {
                 ifds.getForField(ft, "test", () -> { throw new UnsupportedOperationException(); }); // no exception
             } else {
-                IllegalArgumentException e = expectThrows(
-                    IllegalArgumentException.class,
-                    () -> ifds.getForField(ft, "test", () -> { throw new UnsupportedOperationException(); })
-                );
+                IllegalArgumentException e = expectThrows(IllegalArgumentException.class, () -> ifds.getForField(ft, "test", () -> {
+                    throw new UnsupportedOperationException();
+                }));
                 assertThat(e.getMessage(), containsString("doc values"));
             }
         } finally {
diff --git a/server/src/test/java/org/opensearch/index/get/DocumentFieldTests.java b/server/src/test/java/org/opensearch/index/get/DocumentFieldTests.java
index a2cf04c072892..cc1d3fe17e1d3 100644
--- a/server/src/test/java/org/opensearch/index/get/DocumentFieldTests.java
+++ b/server/src/test/java/org/opensearch/index/get/DocumentFieldTests.java
@@ -34,7 +34,6 @@
 
 import org.opensearch.common.Strings;
 import org.opensearch.common.bytes.BytesReference;
-import org.opensearch.common.collect.Map;
 import org.opensearch.common.collect.Tuple;
 import org.opensearch.common.document.DocumentField;
 import org.opensearch.common.xcontent.ToXContent;
@@ -49,6 +48,7 @@
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
+import java.util.Map;
 import java.util.function.Predicate;
 import java.util.function.Supplier;
 
diff --git a/server/src/test/java/org/opensearch/index/mapper/DateFieldMapperTests.java b/server/src/test/java/org/opensearch/index/mapper/DateFieldMapperTests.java
index 918b86761fe86..9e1d3f1e08bc2 100644
--- a/server/src/test/java/org/opensearch/index/mapper/DateFieldMapperTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/DateFieldMapperTests.java
@@ -34,7 +34,6 @@
 
 import org.apache.lucene.index.DocValuesType;
 import org.apache.lucene.index.IndexableField;
-import org.opensearch.common.collect.List;
 import org.opensearch.common.time.DateFormatter;
 import org.opensearch.common.xcontent.XContentBuilder;
 import org.opensearch.index.termvectors.TermVectorsService;
@@ -44,6 +43,7 @@
 import java.time.ZoneId;
 import java.time.ZoneOffset;
 import java.time.ZonedDateTime;
+import java.util.List;
 
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.notNullValue;
diff --git a/server/src/test/java/org/opensearch/index/mapper/DocumentMapperTests.java b/server/src/test/java/org/opensearch/index/mapper/DocumentMapperTests.java
index 9a1113d04a6f6..fa6ef72552faf 100644
--- a/server/src/test/java/org/opensearch/index/mapper/DocumentMapperTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/DocumentMapperTests.java
@@ -266,12 +266,7 @@ public void testMergeMetaForIndexTemplate() throws IOException {
             b.endObject();
         }));
 
-        Map<String, Object> expected = org.opensearch.common.collect.Map.of(
-            "field",
-            "value",
-            "object",
-            org.opensearch.common.collect.Map.of("field1", "value1", "field2", "value2")
-        );
+        Map<String, Object> expected = Map.of("field", "value", "object", Map.of("field1", "value1", "field2", "value2"));
         assertThat(initMapper.meta(), equalTo(expected));
 
         DocumentMapper updatedMapper = createDocumentMapper(fieldMapping(b -> b.field("type", "text")));
@@ -293,12 +288,7 @@ public void testMergeMetaForIndexTemplate() throws IOException {
         }));
         mergedMapper = mergedMapper.merge(updatedMapper.mapping(), MergeReason.INDEX_TEMPLATE);
 
-        expected = org.opensearch.common.collect.Map.of(
-            "field",
-            "value",
-            "object",
-            org.opensearch.common.collect.Map.of("field1", "value1", "field2", "new_value", "field3", "value3")
-        );
+        expected = Map.of("field", "value", "object", Map.of("field1", "value1", "field2", "new_value", "field3", "value3"));
         assertThat(mergedMapper.meta(), equalTo(expected));
     }
 }
diff --git a/server/src/test/java/org/opensearch/index/mapper/DocumentParserTests.java b/server/src/test/java/org/opensearch/index/mapper/DocumentParserTests.java
index 659042c37d650..6d69e62bc7dd8 100644
--- a/server/src/test/java/org/opensearch/index/mapper/DocumentParserTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/DocumentParserTests.java
@@ -1486,4 +1486,156 @@ public void testTypeless() throws IOException {
         ParsedDocument doc = mapper.parse(source(b -> b.field("foo", "1234")));
         assertNull(doc.dynamicMappingsUpdate()); // no update since we reused the existing type
     }
+
+    public void testDocumentContainsDeepNestedFieldParsing() throws Exception {
+        DocumentMapper mapper = createDocumentMapper(mapping(b -> {}));
+        ParsedDocument doc = mapper.parse(source(b -> {
+            b.startObject("inner1");
+            {
+                b.field("inner1_field1", "inner1_value1");
+                b.startObject("inner2");
+                {
+                    b.startObject("inner3");
+                    {
+                        b.field("inner3_field1", "inner3_value1");
+                        b.field("inner3_field2", "inner3_value2");
+                    }
+                    b.endObject();
+                }
+                b.endObject();
+            }
+            b.endObject();
+        }));
+
+        Mapping update = doc.dynamicMappingsUpdate();
+        assertNotNull(update); // dynamic mapping update
+
+        Mapper objMapper = update.root().getMapper("inner1");
+        Mapper inner1_field1_mapper = ((ObjectMapper) objMapper).getMapper("inner1_field1");
+        assertNotNull(inner1_field1_mapper);
+        Mapper inner2_mapper = ((ObjectMapper) objMapper).getMapper("inner2");
+        assertNotNull(inner2_mapper);
+        Mapper inner3_mapper = ((ObjectMapper) inner2_mapper).getMapper("inner3");
+        assertNotNull(inner3_mapper);
+        assertThat(doc.rootDoc().get("inner1.inner2.inner3.inner3_field1"), equalTo("inner3_value1"));
+    }
+
+    public void testDocumentContainsDeepNestedFieldParsingFail() throws Exception {
+        DocumentMapper mapper = createDocumentMapper(mapping(b -> {}));
+        long depth_limit = MapperService.INDEX_MAPPING_DEPTH_LIMIT_SETTING.getDefault(Settings.EMPTY);
+        MapperParsingException e = expectThrows(MapperParsingException.class, () -> mapper.parse(source(b -> {
+            for (int i = 1; i <= depth_limit; i++) {
+                b.startObject("inner" + i);
+            }
+            b.field("inner_field", "inner_value");
+            for (int i = 1; i <= depth_limit; i++) {
+                b.endObject();
+            }
+        })));
+
+        // check that parsing succeeds with valid doc
+        // after throwing exception
+        ParsedDocument doc = mapper.parse(source(b -> {
+            b.startObject("inner1");
+            {
+                b.startObject("inner2");
+                {
+                    b.startObject("inner3");
+                    {
+                        b.field("inner3_field1", "inner3_value1");
+                    }
+                    b.endObject();
+                }
+                b.endObject();
+            }
+            b.endObject();
+        }));
+
+        Mapping update = doc.dynamicMappingsUpdate();
+        assertNotNull(update); // dynamic mapping update
+        Mapper objMapper = update.root().getMapper("inner1");
+        Mapper inner2_mapper = ((ObjectMapper) objMapper).getMapper("inner2");
+        assertNotNull(inner2_mapper);
+        Mapper inner3_mapper = ((ObjectMapper) inner2_mapper).getMapper("inner3");
+        assertNotNull(inner3_mapper);
+        assertThat(doc.rootDoc().get("inner1.inner2.inner3.inner3_field1"), equalTo("inner3_value1"));
+    }
+
+    public void testDocumentContainsDeepNestedFieldParsingShouldFail() throws Exception {
+        DocumentMapper mapper = createDocumentMapper(fieldMapping(b -> { b.field("type", "nested"); }));
+        long depth_limit = MapperService.INDEX_MAPPING_DEPTH_LIMIT_SETTING.getDefault(Settings.EMPTY);
+        MapperParsingException e = expectThrows(MapperParsingException.class, () -> mapper.parse(source(b -> {
+            b.startObject("field");
+            b.startArray("inner");
+            for (int i = 1; i <= depth_limit; i++) {
+                b.startArray();
+            }
+            b.startArray().value(0).value(0).endArray();
+            for (int i = 1; i <= depth_limit; i++) {
+                b.endArray();
+            }
+            b.endArray();
+            b.endObject();
+        })));
+        // check parsing success for nested array within allowed depth limit
+        ParsedDocument doc = mapper.parse(source(b -> {
+            b.startObject("field");
+            b.startArray("inner");
+            for (int i = 1; i < depth_limit - 1; i++) {
+                b.startArray();
+            }
+            b.startArray().value(0).value(0).endArray();
+            for (int i = 1; i < depth_limit - 1; i++) {
+                b.endArray();
+            }
+            b.endArray();
+            b.endObject();
+        }
+
+        ));
+        Mapping update = doc.dynamicMappingsUpdate();
+        assertNotNull(update); // dynamic mapping update
+
+    }
+
+    // Test nesting upto max allowed depth with combination of nesting in object and array
+    // object -> array -> object -> array ....
+    public void testDocumentDeepNestedObjectAndArrayCombination() throws Exception {
+        DocumentMapper mapper = createDocumentMapper(mapping(b -> {}));
+        long depth_limit = MapperService.INDEX_MAPPING_DEPTH_LIMIT_SETTING.getDefault(Settings.EMPTY);
+        MapperParsingException e = expectThrows(MapperParsingException.class, () -> mapper.parse(source(b -> {
+            for (int i = 1; i < depth_limit; i++) {
+                b.startArray("foo" + 1);
+                b.startObject();
+            }
+            b.startArray("bar");
+            b.startArray().value(0).value(0).endArray();
+            b.endArray();
+            for (int i = 1; i < depth_limit; i++) {
+                b.endObject();
+                b.endArray();
+            }
+        })));
+
+        // check parsing success for nested array within allowed depth limit
+        ParsedDocument doc = mapper.parse(source(b -> {
+            for (int i = 1; i < depth_limit - 1; i++) {
+                b.startArray("foo" + 1);
+                b.startObject();
+            }
+            b.startArray("bar");
+            b.startArray().value(0).value(0).endArray();
+            b.endArray();
+            for (int i = 1; i < depth_limit - 1; i++) {
+                b.endObject();
+                b.endArray();
+            }
+        }
+
+        ));
+        Mapping update = doc.dynamicMappingsUpdate();
+        assertNotNull(update); // dynamic mapping update
+
+    }
+
 }
diff --git a/server/src/test/java/org/opensearch/index/mapper/FieldTypeLookupTests.java b/server/src/test/java/org/opensearch/index/mapper/FieldTypeLookupTests.java
index 9aa9c7d5074e7..583f9ab48edad 100644
--- a/server/src/test/java/org/opensearch/index/mapper/FieldTypeLookupTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/FieldTypeLookupTests.java
@@ -32,13 +32,13 @@
 
 package org.opensearch.index.mapper;
 
-import org.opensearch.common.collect.Set;
 import org.opensearch.test.OpenSearchTestCase;
 
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Iterator;
+import java.util.Set;
 
 import static java.util.Collections.emptyList;
 import static java.util.Collections.singletonList;
diff --git a/server/src/test/java/org/opensearch/index/mapper/GeoPointFieldMapperTests.java b/server/src/test/java/org/opensearch/index/mapper/GeoPointFieldMapperTests.java
index 1b4c95d9ceb8f..5ace447afd91e 100644
--- a/server/src/test/java/org/opensearch/index/mapper/GeoPointFieldMapperTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/GeoPointFieldMapperTests.java
@@ -56,7 +56,7 @@ public class GeoPointFieldMapperTests extends FieldMapperTestCase2<GeoPointField
 
     @Override
     protected Set<String> unsupportedProperties() {
-        return org.opensearch.common.collect.Set.of("analyzer", "similarity", "doc_values");
+        return Set.of("analyzer", "similarity", "doc_values");
     }
 
     @Override
diff --git a/server/src/test/java/org/opensearch/index/mapper/GeoShapeFieldMapperTests.java b/server/src/test/java/org/opensearch/index/mapper/GeoShapeFieldMapperTests.java
index 6e3216e934b07..a1622f8e9de09 100644
--- a/server/src/test/java/org/opensearch/index/mapper/GeoShapeFieldMapperTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/GeoShapeFieldMapperTests.java
@@ -33,7 +33,6 @@
 
 import org.opensearch.common.Explicit;
 import org.opensearch.common.Strings;
-import org.opensearch.common.collect.List;
 import org.opensearch.common.geo.builders.ShapeBuilder;
 import org.opensearch.common.xcontent.ToXContent;
 import org.opensearch.common.xcontent.XContentBuilder;
@@ -45,6 +44,7 @@
 import java.io.IOException;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.List;
 import java.util.Set;
 
 import static org.hamcrest.Matchers.containsString;
@@ -56,7 +56,7 @@ public class GeoShapeFieldMapperTests extends FieldMapperTestCase2<GeoShapeField
 
     @Override
     protected Set<String> unsupportedProperties() {
-        return org.opensearch.common.collect.Set.of("analyzer", "similarity", "doc_values", "store");
+        return Set.of("analyzer", "similarity", "doc_values", "store");
     }
 
     @Override
diff --git a/server/src/test/java/org/opensearch/index/mapper/GeoShapeFieldTypeTests.java b/server/src/test/java/org/opensearch/index/mapper/GeoShapeFieldTypeTests.java
index f4767403ffbf7..127117ee9c7b2 100644
--- a/server/src/test/java/org/opensearch/index/mapper/GeoShapeFieldTypeTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/GeoShapeFieldTypeTests.java
@@ -49,13 +49,13 @@ public void testFetchSourceValue() throws IOException {
 
         MappedFieldType mapper = new GeoShapeFieldMapper.Builder("field").build(context).fieldType();
 
-        Map<String, Object> jsonLineString = org.opensearch.common.collect.Map.of(
+        Map<String, Object> jsonLineString = Map.of(
             "type",
             "LineString",
             "coordinates",
             Arrays.asList(Arrays.asList(42.0, 27.1), Arrays.asList(30.0, 50.0))
         );
-        Map<String, Object> jsonPoint = org.opensearch.common.collect.Map.of("type", "Point", "coordinates", Arrays.asList(14.0, 15.0));
+        Map<String, Object> jsonPoint = Map.of("type", "Point", "coordinates", Arrays.asList(14.0, 15.0));
         String wktLineString = "LINESTRING (42.0 27.1, 30.0 50.0)";
         String wktPoint = "POINT (14.0 15.0)";
 
diff --git a/server/src/test/java/org/opensearch/index/mapper/IdFieldMapperTests.java b/server/src/test/java/org/opensearch/index/mapper/IdFieldMapperTests.java
index e897abad405d5..93d0596a9bfb5 100644
--- a/server/src/test/java/org/opensearch/index/mapper/IdFieldMapperTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/IdFieldMapperTests.java
@@ -114,10 +114,9 @@ public void testEnableFieldData() throws IOException {
             .setTransientSettings(Settings.builder().put(IndicesService.INDICES_ID_FIELD_DATA_ENABLED_SETTING.getKey(), false))
             .get();
         try {
-            IllegalArgumentException exc = expectThrows(
-                IllegalArgumentException.class,
-                () -> ft.fielddataBuilder("test", () -> { throw new UnsupportedOperationException(); }).build(null, null)
-            );
+            IllegalArgumentException exc = expectThrows(IllegalArgumentException.class, () -> ft.fielddataBuilder("test", () -> {
+                throw new UnsupportedOperationException();
+            }).build(null, null));
             assertThat(exc.getMessage(), containsString(IndicesService.INDICES_ID_FIELD_DATA_ENABLED_SETTING.getKey()));
             assertFalse(ft.isAggregatable());
         } finally {
diff --git a/server/src/test/java/org/opensearch/index/mapper/IpRangeFieldTypeTests.java b/server/src/test/java/org/opensearch/index/mapper/IpRangeFieldTypeTests.java
index c2c6293eec4bd..36edc4e92504b 100644
--- a/server/src/test/java/org/opensearch/index/mapper/IpRangeFieldTypeTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/IpRangeFieldTypeTests.java
@@ -47,11 +47,8 @@ public void testFetchSourceValue() throws IOException {
         Mapper.BuilderContext context = new Mapper.BuilderContext(settings, new ContentPath());
 
         RangeFieldMapper mapper = new RangeFieldMapper.Builder("field", RangeType.IP, true, Version.V_EMPTY).build(context);
-        Map<String, Object> range = org.opensearch.common.collect.Map.of("gte", "2001:db8:0:0:0:0:2:1");
-        assertEquals(
-            Collections.singletonList(org.opensearch.common.collect.Map.of("gte", "2001:db8::2:1")),
-            fetchSourceValue(mapper.fieldType(), range)
-        );
+        Map<String, Object> range = Map.of("gte", "2001:db8:0:0:0:0:2:1");
+        assertEquals(Collections.singletonList(Map.of("gte", "2001:db8::2:1")), fetchSourceValue(mapper.fieldType(), range));
         assertEquals(Collections.singletonList("2001:db8::2:1/32"), fetchSourceValue(mapper.fieldType(), "2001:db8:0:0:0:0:2:1/32"));
     }
 }
diff --git a/server/src/test/java/org/opensearch/index/mapper/KeywordFieldMapperTests.java b/server/src/test/java/org/opensearch/index/mapper/KeywordFieldMapperTests.java
index 7059e908c078f..3968742fddfef 100644
--- a/server/src/test/java/org/opensearch/index/mapper/KeywordFieldMapperTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/KeywordFieldMapperTests.java
@@ -134,7 +134,7 @@ protected Collection<? extends Plugin> getPlugins() {
     protected IndexAnalyzers createIndexAnalyzers(IndexSettings indexSettings) {
         return new IndexAnalyzers(
             singletonMap("default", new NamedAnalyzer("default", AnalyzerScope.INDEX, new StandardAnalyzer())),
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 "lowercase",
                 new NamedAnalyzer("lowercase", AnalyzerScope.INDEX, new LowercaseNormalizer()),
                 "other_lowercase",
diff --git a/server/src/test/java/org/opensearch/index/mapper/KeywordFieldTypeTests.java b/server/src/test/java/org/opensearch/index/mapper/KeywordFieldTypeTests.java
index 6b7216a584ca9..ad529c685d6f3 100644
--- a/server/src/test/java/org/opensearch/index/mapper/KeywordFieldTypeTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/KeywordFieldTypeTests.java
@@ -72,6 +72,7 @@
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
+import java.util.Map;
 
 public class KeywordFieldTypeTests extends FieldTypeTestCase {
 
@@ -245,18 +246,12 @@ public void testFetchSourceValue() throws IOException {
 
     private static IndexAnalyzers createIndexAnalyzers() {
         return new IndexAnalyzers(
-            org.opensearch.common.collect.Map.of("default", new NamedAnalyzer("default", AnalyzerScope.INDEX, new StandardAnalyzer())),
-            org.opensearch.common.collect.Map.ofEntries(
-                org.opensearch.common.collect.Map.entry(
-                    "lowercase",
-                    new NamedAnalyzer("lowercase", AnalyzerScope.INDEX, new LowercaseNormalizer())
-                ),
-                org.opensearch.common.collect.Map.entry(
-                    "other_lowercase",
-                    new NamedAnalyzer("other_lowercase", AnalyzerScope.INDEX, new LowercaseNormalizer())
-                )
+            Map.of("default", new NamedAnalyzer("default", AnalyzerScope.INDEX, new StandardAnalyzer())),
+            Map.ofEntries(
+                Map.entry("lowercase", new NamedAnalyzer("lowercase", AnalyzerScope.INDEX, new LowercaseNormalizer())),
+                Map.entry("other_lowercase", new NamedAnalyzer("other_lowercase", AnalyzerScope.INDEX, new LowercaseNormalizer()))
             ),
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 "lowercase",
                 new NamedAnalyzer(
                     "lowercase",
diff --git a/server/src/test/java/org/opensearch/index/mapper/LegacyGeoShapeFieldMapperTests.java b/server/src/test/java/org/opensearch/index/mapper/LegacyGeoShapeFieldMapperTests.java
index b43b7c51df1c7..a4dc54a74e912 100644
--- a/server/src/test/java/org/opensearch/index/mapper/LegacyGeoShapeFieldMapperTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/LegacyGeoShapeFieldMapperTests.java
@@ -39,7 +39,6 @@
 import org.opensearch.OpenSearchException;
 import org.opensearch.common.Explicit;
 import org.opensearch.common.Strings;
-import org.opensearch.common.collect.List;
 import org.opensearch.common.geo.GeoUtils;
 import org.opensearch.common.geo.ShapeRelation;
 import org.opensearch.common.geo.SpatialStrategy;
@@ -54,6 +53,7 @@
 
 import java.io.IOException;
 import java.util.Collection;
+import java.util.List;
 import java.util.Set;
 
 import static java.util.Collections.singletonMap;
@@ -80,7 +80,7 @@ protected LegacyGeoShapeFieldMapper.Builder newBuilder() {
 
     @Override
     protected Set<String> unsupportedProperties() {
-        return org.opensearch.common.collect.Set.of("analyzer", "similarity", "doc_values", "store");
+        return Set.of("analyzer", "similarity", "doc_values", "store");
     }
 
     @Override
diff --git a/server/src/test/java/org/opensearch/index/mapper/LegacyGeoShapeFieldTypeTests.java b/server/src/test/java/org/opensearch/index/mapper/LegacyGeoShapeFieldTypeTests.java
index 5157232bea1a2..45161bed1d40e 100644
--- a/server/src/test/java/org/opensearch/index/mapper/LegacyGeoShapeFieldTypeTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/LegacyGeoShapeFieldTypeTests.java
@@ -63,13 +63,13 @@ public void testFetchSourceValue() throws IOException {
 
         MappedFieldType mapper = new LegacyGeoShapeFieldMapper.Builder("field").build(context).fieldType();
 
-        Map<String, Object> jsonLineString = org.opensearch.common.collect.Map.of(
+        Map<String, Object> jsonLineString = Map.of(
             "type",
             "LineString",
             "coordinates",
             Arrays.asList(Arrays.asList(42.0, 27.1), Arrays.asList(30.0, 50.0))
         );
-        Map<String, Object> jsonPoint = org.opensearch.common.collect.Map.of("type", "Point", "coordinates", Arrays.asList(14.0, 15.0));
+        Map<String, Object> jsonPoint = Map.of("type", "Point", "coordinates", Arrays.asList(14.0, 15.0));
         String wktLineString = "LINESTRING (42.0 27.1, 30.0 50.0)";
         String wktPoint = "POINT (14.0 15.0)";
 
diff --git a/server/src/test/java/org/opensearch/index/mapper/MapperServiceTests.java b/server/src/test/java/org/opensearch/index/mapper/MapperServiceTests.java
index b58c0bf69c298..e58edb33f0718 100644
--- a/server/src/test/java/org/opensearch/index/mapper/MapperServiceTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/MapperServiceTests.java
@@ -340,10 +340,9 @@ public void testFieldNameLengthLimit() throws Throwable {
             )
         );
 
-        IllegalArgumentException e = expectThrows(
-            IllegalArgumentException.class,
-            () -> { mapperService.merge("type", mappingUpdate, updateOrPreflight()); }
-        );
+        IllegalArgumentException e = expectThrows(IllegalArgumentException.class, () -> {
+            mapperService.merge("type", mappingUpdate, updateOrPreflight());
+        });
 
         assertEquals("Field name [" + testString + "] is longer than the limit of [" + maxFieldNameLength + "] characters", e.getMessage());
     }
@@ -371,10 +370,9 @@ public void testObjectNameLengthLimit() throws Throwable {
             )
         );
 
-        IllegalArgumentException e = expectThrows(
-            IllegalArgumentException.class,
-            () -> { mapperService.merge("type", mapping, updateOrPreflight()); }
-        );
+        IllegalArgumentException e = expectThrows(IllegalArgumentException.class, () -> {
+            mapperService.merge("type", mapping, updateOrPreflight());
+        });
 
         assertEquals("Field name [" + testString + "] is longer than the limit of [" + maxFieldNameLength + "] characters", e.getMessage());
     }
@@ -406,10 +404,9 @@ public void testAliasFieldNameLengthLimit() throws Throwable {
             )
         );
 
-        IllegalArgumentException e = expectThrows(
-            IllegalArgumentException.class,
-            () -> { mapperService.merge("type", mapping, updateOrPreflight()); }
-        );
+        IllegalArgumentException e = expectThrows(IllegalArgumentException.class, () -> {
+            mapperService.merge("type", mapping, updateOrPreflight());
+        });
 
         assertEquals("Field name [" + testString + "] is longer than the limit of [" + maxFieldNameLength + "] characters", e.getMessage());
     }
diff --git a/server/src/test/java/org/opensearch/index/mapper/NumberFieldMapperTests.java b/server/src/test/java/org/opensearch/index/mapper/NumberFieldMapperTests.java
index 81d4d8b994ee3..56357540393b2 100644
--- a/server/src/test/java/org/opensearch/index/mapper/NumberFieldMapperTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/NumberFieldMapperTests.java
@@ -55,12 +55,12 @@ public class NumberFieldMapperTests extends AbstractNumericFieldMapperTestCase {
 
     @Override
     protected Set<String> types() {
-        return org.opensearch.common.collect.Set.of("byte", "short", "integer", "long", "float", "double", "half_float");
+        return Set.of("byte", "short", "integer", "long", "float", "double", "half_float");
     }
 
     @Override
     protected Set<String> wholeTypes() {
-        return org.opensearch.common.collect.Set.of("byte", "short", "integer", "long");
+        return Set.of("byte", "short", "integer", "long");
     }
 
     @Override
diff --git a/server/src/test/java/org/opensearch/index/mapper/NumberFieldTypeTests.java b/server/src/test/java/org/opensearch/index/mapper/NumberFieldTypeTests.java
index ca5e8d0c6e08d..910f242b59e61 100644
--- a/server/src/test/java/org/opensearch/index/mapper/NumberFieldTypeTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/NumberFieldTypeTests.java
@@ -553,10 +553,9 @@ public void doTestIndexSortRangeQueries(NumberType type, Supplier<Number> valueS
 
         // Create an index writer configured with the same index sort.
         NumberFieldType fieldType = new NumberFieldType("field", type);
-        IndexNumericFieldData fielddata = (IndexNumericFieldData) fieldType.fielddataBuilder(
-            "index",
-            () -> { throw new UnsupportedOperationException(); }
-        ).build(null, null);
+        IndexNumericFieldData fielddata = (IndexNumericFieldData) fieldType.fielddataBuilder("index", () -> {
+            throw new UnsupportedOperationException();
+        }).build(null, null);
         SortField sortField = fielddata.sortField(null, MultiValueMode.MIN, null, randomBoolean());
 
         IndexWriterConfig writerConfig = new IndexWriterConfig();
diff --git a/server/src/test/java/org/opensearch/index/mapper/ObjectMapperTests.java b/server/src/test/java/org/opensearch/index/mapper/ObjectMapperTests.java
index d6c89342c9df2..07b0ad822209c 100644
--- a/server/src/test/java/org/opensearch/index/mapper/ObjectMapperTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/ObjectMapperTests.java
@@ -443,10 +443,9 @@ public void testEmptyName() throws Exception {
         );
 
         // Empty name not allowed in index created after 5.0
-        IllegalArgumentException e = expectThrows(
-            IllegalArgumentException.class,
-            () -> { createIndex("test").mapperService().documentMapperParser().parse("", new CompressedXContent(mapping)); }
-        );
+        IllegalArgumentException e = expectThrows(IllegalArgumentException.class, () -> {
+            createIndex("test").mapperService().documentMapperParser().parse("", new CompressedXContent(mapping));
+        });
         assertThat(e.getMessage(), containsString("name cannot be empty string"));
     }
 
diff --git a/server/src/test/java/org/opensearch/index/mapper/ParametrizedMapperTests.java b/server/src/test/java/org/opensearch/index/mapper/ParametrizedMapperTests.java
index 3cd6df601089a..5286b06980ee1 100644
--- a/server/src/test/java/org/opensearch/index/mapper/ParametrizedMapperTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/ParametrizedMapperTests.java
@@ -69,7 +69,7 @@ public class ParametrizedMapperTests extends MapperServiceTestCase {
     public static class TestPlugin extends Plugin implements MapperPlugin {
         @Override
         public Map<String, Mapper.TypeParser> getMappers() {
-            return org.opensearch.common.collect.Map.of("test_mapper", new TypeParser());
+            return Map.of("test_mapper", new TypeParser());
         }
     }
 
@@ -219,7 +219,7 @@ protected String contentType() {
     private static TestMapper fromMapping(String mapping, Version version) {
         MapperService mapperService = mock(MapperService.class);
         IndexAnalyzers indexAnalyzers = new IndexAnalyzers(
-            org.opensearch.common.collect.Map.of(
+            Map.of(
                 "_standard",
                 Lucene.STANDARD_ANALYZER,
                 "_keyword",
diff --git a/server/src/test/java/org/opensearch/index/mapper/RangeFieldMapperTests.java b/server/src/test/java/org/opensearch/index/mapper/RangeFieldMapperTests.java
index 0353173e25696..5e20ff8122d30 100644
--- a/server/src/test/java/org/opensearch/index/mapper/RangeFieldMapperTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/RangeFieldMapperTests.java
@@ -68,12 +68,12 @@ public class RangeFieldMapperTests extends AbstractNumericFieldMapperTestCase {
 
     @Override
     protected Set<String> types() {
-        return org.opensearch.common.collect.Set.of("date_range", "ip_range", "float_range", "double_range", "integer_range", "long_range");
+        return Set.of("date_range", "ip_range", "float_range", "double_range", "integer_range", "long_range");
     }
 
     @Override
     protected Set<String> wholeTypes() {
-        return org.opensearch.common.collect.Set.of("integer_range", "long_range");
+        return Set.of("integer_range", "long_range");
     }
 
     @Override
diff --git a/server/src/test/java/org/opensearch/index/mapper/RangeFieldTypeTests.java b/server/src/test/java/org/opensearch/index/mapper/RangeFieldTypeTests.java
index d4772f24cca93..668666a53cd7c 100644
--- a/server/src/test/java/org/opensearch/index/mapper/RangeFieldTypeTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/RangeFieldTypeTests.java
@@ -538,20 +538,14 @@ public void testFetchSourceValue() throws IOException {
 
         MappedFieldType longMapper = new RangeFieldMapper.Builder("field", RangeType.LONG, true, Version.V_EMPTY).build(context)
             .fieldType();
-        Map<String, Object> longRange = org.opensearch.common.collect.Map.of("gte", 3.14, "lt", "42.9");
-        assertEquals(
-            Collections.singletonList(org.opensearch.common.collect.Map.of("gte", 3L, "lt", 42L)),
-            fetchSourceValue(longMapper, longRange)
-        );
+        Map<String, Object> longRange = Map.of("gte", 3.14, "lt", "42.9");
+        assertEquals(Collections.singletonList(Map.of("gte", 3L, "lt", 42L)), fetchSourceValue(longMapper, longRange));
 
         MappedFieldType dateMapper = new RangeFieldMapper.Builder("field", RangeType.DATE, true, Version.V_EMPTY).format(
             "yyyy/MM/dd||epoch_millis"
         ).build(context).fieldType();
-        Map<String, Object> dateRange = org.opensearch.common.collect.Map.of("lt", "1990/12/29", "gte", 597429487111L);
-        assertEquals(
-            Collections.singletonList(org.opensearch.common.collect.Map.of("lt", "1990/12/29", "gte", "1988/12/06")),
-            fetchSourceValue(dateMapper, dateRange)
-        );
+        Map<String, Object> dateRange = Map.of("lt", "1990/12/29", "gte", 597429487111L);
+        assertEquals(Collections.singletonList(Map.of("lt", "1990/12/29", "gte", "1988/12/06")), fetchSourceValue(dateMapper, dateRange));
     }
 
     public void testParseSourceValueWithFormat() throws IOException {
@@ -560,23 +554,14 @@ public void testParseSourceValueWithFormat() throws IOException {
 
         MappedFieldType longMapper = new RangeFieldMapper.Builder("field", RangeType.LONG, true, Version.V_EMPTY).build(context)
             .fieldType();
-        Map<String, Object> longRange = org.opensearch.common.collect.Map.of("gte", 3.14, "lt", "42.9");
-        assertEquals(
-            Collections.singletonList(org.opensearch.common.collect.Map.of("gte", 3L, "lt", 42L)),
-            fetchSourceValue(longMapper, longRange)
-        );
+        Map<String, Object> longRange = Map.of("gte", 3.14, "lt", "42.9");
+        assertEquals(Collections.singletonList(Map.of("gte", 3L, "lt", 42L)), fetchSourceValue(longMapper, longRange));
 
         MappedFieldType dateMapper = new RangeFieldMapper.Builder("field", RangeType.DATE, true, Version.V_EMPTY).format("strict_date_time")
             .build(context)
             .fieldType();
-        Map<String, Object> dateRange = org.opensearch.common.collect.Map.of("lt", "1990-12-29T00:00:00.000Z");
-        assertEquals(
-            Collections.singletonList(org.opensearch.common.collect.Map.of("lt", "1990/12/29")),
-            fetchSourceValue(dateMapper, dateRange, "yyy/MM/dd")
-        );
-        assertEquals(
-            Collections.singletonList(org.opensearch.common.collect.Map.of("lt", "662428800000")),
-            fetchSourceValue(dateMapper, dateRange, "epoch_millis")
-        );
+        Map<String, Object> dateRange = Map.of("lt", "1990-12-29T00:00:00.000Z");
+        assertEquals(Collections.singletonList(Map.of("lt", "1990/12/29")), fetchSourceValue(dateMapper, dateRange, "yyy/MM/dd"));
+        assertEquals(Collections.singletonList(Map.of("lt", "662428800000")), fetchSourceValue(dateMapper, dateRange, "epoch_millis"));
     }
 }
diff --git a/server/src/test/java/org/opensearch/index/mapper/TextFieldMapperTests.java b/server/src/test/java/org/opensearch/index/mapper/TextFieldMapperTests.java
index a56ab2713d498..4148fe0bfea1b 100644
--- a/server/src/test/java/org/opensearch/index/mapper/TextFieldMapperTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/TextFieldMapperTests.java
@@ -230,20 +230,9 @@ public TokenStream create(TokenStream tokenStream) {
             )
         );
         return new IndexAnalyzers(
-            org.opensearch.common.collect.Map.of(
-                "default",
-                dflt,
-                "standard",
-                standard,
-                "keyword",
-                keyword,
-                "whitespace",
-                whitespace,
-                "my_stop_analyzer",
-                stop
-            ),
-            org.opensearch.common.collect.Map.of(),
-            org.opensearch.common.collect.Map.of()
+            Map.of("default", dflt, "standard", standard, "keyword", keyword, "whitespace", whitespace, "my_stop_analyzer", stop),
+            Map.of(),
+            Map.of()
         );
     }
 
@@ -512,10 +501,9 @@ public void testEagerGlobalOrdinals() throws IOException {
 
     public void testFielddata() throws IOException {
         MapperService disabledMapper = createMapperService(fieldMapping(this::minimalMapping));
-        Exception e = expectThrows(
-            IllegalArgumentException.class,
-            () -> disabledMapper.fieldType("field").fielddataBuilder("test", () -> { throw new UnsupportedOperationException(); })
-        );
+        Exception e = expectThrows(IllegalArgumentException.class, () -> disabledMapper.fieldType("field").fielddataBuilder("test", () -> {
+            throw new UnsupportedOperationException();
+        }));
         assertThat(e.getMessage(), containsString("Text fields are not optimised for operations that require per-document field data"));
 
         MapperService enabledMapper = createMapperService(fieldMapping(b -> b.field("type", "text").field("fielddata", true)));
diff --git a/server/src/test/java/org/opensearch/index/mapper/TextFieldTypeTests.java b/server/src/test/java/org/opensearch/index/mapper/TextFieldTypeTests.java
index b9ec5a07b207d..206be8c8352ef 100644
--- a/server/src/test/java/org/opensearch/index/mapper/TextFieldTypeTests.java
+++ b/server/src/test/java/org/opensearch/index/mapper/TextFieldTypeTests.java
@@ -207,18 +207,18 @@ public void testFetchSourceValue() throws IOException {
         TextFieldType fieldType = createFieldType();
         fieldType.setIndexAnalyzer(Lucene.STANDARD_ANALYZER);
 
-        assertEquals(org.opensearch.common.collect.List.of("value"), fetchSourceValue(fieldType, "value"));
-        assertEquals(org.opensearch.common.collect.List.of("42"), fetchSourceValue(fieldType, 42L));
-        assertEquals(org.opensearch.common.collect.List.of("true"), fetchSourceValue(fieldType, true));
+        assertEquals(List.of("value"), fetchSourceValue(fieldType, "value"));
+        assertEquals(List.of("42"), fetchSourceValue(fieldType, 42L));
+        assertEquals(List.of("true"), fetchSourceValue(fieldType, true));
 
         TextFieldMapper.PrefixFieldType prefixFieldType = new TextFieldMapper.PrefixFieldType(fieldType, "field._index_prefix", 2, 10);
-        assertEquals(org.opensearch.common.collect.List.of("value"), fetchSourceValue(prefixFieldType, "value"));
-        assertEquals(org.opensearch.common.collect.List.of("42"), fetchSourceValue(prefixFieldType, 42L));
-        assertEquals(org.opensearch.common.collect.List.of("true"), fetchSourceValue(prefixFieldType, true));
+        assertEquals(List.of("value"), fetchSourceValue(prefixFieldType, "value"));
+        assertEquals(List.of("42"), fetchSourceValue(prefixFieldType, 42L));
+        assertEquals(List.of("true"), fetchSourceValue(prefixFieldType, true));
 
         TextFieldMapper.PhraseFieldType phraseFieldType = new TextFieldMapper.PhraseFieldType(fieldType);
-        assertEquals(org.opensearch.common.collect.List.of("value"), fetchSourceValue(phraseFieldType, "value"));
-        assertEquals(org.opensearch.common.collect.List.of("42"), fetchSourceValue(phraseFieldType, 42L));
-        assertEquals(org.opensearch.common.collect.List.of("true"), fetchSourceValue(phraseFieldType, true));
+        assertEquals(List.of("value"), fetchSourceValue(phraseFieldType, "value"));
+        assertEquals(List.of("42"), fetchSourceValue(phraseFieldType, 42L));
+        assertEquals(List.of("true"), fetchSourceValue(phraseFieldType, true));
     }
 }
diff --git a/server/src/test/java/org/opensearch/index/query/InnerHitBuilderTests.java b/server/src/test/java/org/opensearch/index/query/InnerHitBuilderTests.java
index bf5e7e30a1410..12bab30dc6285 100644
--- a/server/src/test/java/org/opensearch/index/query/InnerHitBuilderTests.java
+++ b/server/src/test/java/org/opensearch/index/query/InnerHitBuilderTests.java
@@ -237,12 +237,9 @@ static InnerHitBuilder mutate(InnerHitBuilder original) throws IOException {
         });
         modifiers.add(() -> {
             if (randomBoolean()) {
-                copy.setScriptFields(
-                    randomValueOtherThan(
-                        copy.getScriptFields(),
-                        () -> { return new HashSet<>(randomListStuff(16, InnerHitBuilderTests::randomScript)); }
-                    )
-                );
+                copy.setScriptFields(randomValueOtherThan(copy.getScriptFields(), () -> {
+                    return new HashSet<>(randomListStuff(16, InnerHitBuilderTests::randomScript));
+                }));
             } else {
                 SearchSourceBuilder.ScriptField script = randomScript();
                 copy.addScriptField(script.fieldName(), script.script());
diff --git a/server/src/test/java/org/opensearch/index/search/MultiMatchQueryTests.java b/server/src/test/java/org/opensearch/index/search/MultiMatchQueryTests.java
index f0a70b55e0fdd..48d04e2aaa3a6 100644
--- a/server/src/test/java/org/opensearch/index/search/MultiMatchQueryTests.java
+++ b/server/src/test/java/org/opensearch/index/search/MultiMatchQueryTests.java
@@ -111,12 +111,9 @@ public void setup() throws IOException {
     }
 
     public void testCrossFieldMultiMatchQuery() throws IOException {
-        QueryShardContext queryShardContext = indexService.newQueryShardContext(
-            randomInt(20),
-            null,
-            () -> { throw new UnsupportedOperationException(); },
-            null
-        );
+        QueryShardContext queryShardContext = indexService.newQueryShardContext(randomInt(20), null, () -> {
+            throw new UnsupportedOperationException();
+        }, null);
         queryShardContext.setAllowUnmappedFields(true);
         for (float tieBreaker : new float[] { 0.0f, 0.5f }) {
             Query parsedQuery = multiMatchQuery("banon").field("name.first", 2)
@@ -141,14 +138,9 @@ public void testBlendTerms() {
         Term[] terms = new Term[] { new Term("foo", "baz"), new Term("bar", "baz") };
         float[] boosts = new float[] { 2, 3 };
         Query expected = BlendedTermQuery.dismaxBlendedQuery(terms, boosts, 1.0f);
-        Query actual = MultiMatchQuery.blendTerm(
-            indexService.newQueryShardContext(randomInt(20), null, () -> { throw new UnsupportedOperationException(); }, null),
-            new BytesRef("baz"),
-            null,
-            1f,
-            false,
-            Arrays.asList(new FieldAndBoost(ft1, 2), new FieldAndBoost(ft2, 3))
-        );
+        Query actual = MultiMatchQuery.blendTerm(indexService.newQueryShardContext(randomInt(20), null, () -> {
+            throw new UnsupportedOperationException();
+        }, null), new BytesRef("baz"), null, 1f, false, Arrays.asList(new FieldAndBoost(ft1, 2), new FieldAndBoost(ft2, 3)));
         assertEquals(expected, actual);
     }
 
@@ -160,14 +152,9 @@ public void testBlendTermsWithFieldBoosts() {
         Term[] terms = new Term[] { new Term("foo", "baz"), new Term("bar", "baz") };
         float[] boosts = new float[] { 200, 30 };
         Query expected = BlendedTermQuery.dismaxBlendedQuery(terms, boosts, 1.0f);
-        Query actual = MultiMatchQuery.blendTerm(
-            indexService.newQueryShardContext(randomInt(20), null, () -> { throw new UnsupportedOperationException(); }, null),
-            new BytesRef("baz"),
-            null,
-            1f,
-            false,
-            Arrays.asList(new FieldAndBoost(ft1, 2), new FieldAndBoost(ft2, 3))
-        );
+        Query actual = MultiMatchQuery.blendTerm(indexService.newQueryShardContext(randomInt(20), null, () -> {
+            throw new UnsupportedOperationException();
+        }, null), new BytesRef("baz"), null, 1f, false, Arrays.asList(new FieldAndBoost(ft1, 2), new FieldAndBoost(ft2, 3)));
         assertEquals(expected, actual);
     }
 
@@ -188,14 +175,9 @@ public Query termQuery(Object value, QueryShardContext context) {
             ),
             1f
         );
-        Query actual = MultiMatchQuery.blendTerm(
-            indexService.newQueryShardContext(randomInt(20), null, () -> { throw new UnsupportedOperationException(); }, null),
-            new BytesRef("baz"),
-            null,
-            1f,
-            true,
-            Arrays.asList(new FieldAndBoost(ft1, 2), new FieldAndBoost(ft2, 3))
-        );
+        Query actual = MultiMatchQuery.blendTerm(indexService.newQueryShardContext(randomInt(20), null, () -> {
+            throw new UnsupportedOperationException();
+        }, null), new BytesRef("baz"), null, 1f, true, Arrays.asList(new FieldAndBoost(ft1, 2), new FieldAndBoost(ft2, 3)));
         assertEquals(expected, actual);
     }
 
@@ -208,14 +190,9 @@ public Query termQuery(Object value, QueryShardContext context) {
         };
         expectThrows(
             IllegalArgumentException.class,
-            () -> MultiMatchQuery.blendTerm(
-                indexService.newQueryShardContext(randomInt(20), null, () -> { throw new UnsupportedOperationException(); }, null),
-                new BytesRef("baz"),
-                null,
-                1f,
-                false,
-                Arrays.asList(new FieldAndBoost(ft, 1))
-            )
+            () -> MultiMatchQuery.blendTerm(indexService.newQueryShardContext(randomInt(20), null, () -> {
+                throw new UnsupportedOperationException();
+            }, null), new BytesRef("baz"), null, 1f, false, Arrays.asList(new FieldAndBoost(ft, 1)))
         );
     }
 
@@ -232,24 +209,16 @@ public Query termQuery(Object value, QueryShardContext context) {
         Query expectedDisjunct1 = BlendedTermQuery.dismaxBlendedQuery(terms, boosts, 1.0f);
         Query expectedDisjunct2 = new BoostQuery(new MatchAllDocsQuery(), 3);
         Query expected = new DisjunctionMaxQuery(Arrays.asList(expectedDisjunct2, expectedDisjunct1), 1.0f);
-        Query actual = MultiMatchQuery.blendTerm(
-            indexService.newQueryShardContext(randomInt(20), null, () -> { throw new UnsupportedOperationException(); }, null),
-            new BytesRef("baz"),
-            null,
-            1f,
-            false,
-            Arrays.asList(new FieldAndBoost(ft1, 2), new FieldAndBoost(ft2, 3))
-        );
+        Query actual = MultiMatchQuery.blendTerm(indexService.newQueryShardContext(randomInt(20), null, () -> {
+            throw new UnsupportedOperationException();
+        }, null), new BytesRef("baz"), null, 1f, false, Arrays.asList(new FieldAndBoost(ft1, 2), new FieldAndBoost(ft2, 3)));
         assertEquals(expected, actual);
     }
 
     public void testMultiMatchCrossFieldsWithSynonyms() throws IOException {
-        QueryShardContext queryShardContext = indexService.newQueryShardContext(
-            randomInt(20),
-            null,
-            () -> { throw new UnsupportedOperationException(); },
-            null
-        );
+        QueryShardContext queryShardContext = indexService.newQueryShardContext(randomInt(20), null, () -> {
+            throw new UnsupportedOperationException();
+        }, null);
 
         MultiMatchQuery parser = new MultiMatchQuery(queryShardContext);
         parser.setAnalyzer(new MockSynonymAnalyzer());
@@ -279,12 +248,9 @@ public void testMultiMatchCrossFieldsWithSynonyms() throws IOException {
     }
 
     public void testMultiMatchCrossFieldsWithSynonymsPhrase() throws IOException {
-        QueryShardContext queryShardContext = indexService.newQueryShardContext(
-            randomInt(20),
-            null,
-            () -> { throw new UnsupportedOperationException(); },
-            null
-        );
+        QueryShardContext queryShardContext = indexService.newQueryShardContext(randomInt(20), null, () -> {
+            throw new UnsupportedOperationException();
+        }, null);
         MultiMatchQuery parser = new MultiMatchQuery(queryShardContext);
         parser.setAnalyzer(new MockSynonymAnalyzer());
         Map<String, Float> fieldNames = new HashMap<>();
@@ -345,12 +311,9 @@ public void testKeywordSplitQueriesOnWhitespace() throws IOException {
                 .endObject()
         );
         mapperService.merge("type", new CompressedXContent(mapping), MapperService.MergeReason.MAPPING_UPDATE);
-        QueryShardContext queryShardContext = indexService.newQueryShardContext(
-            randomInt(20),
-            null,
-            () -> { throw new UnsupportedOperationException(); },
-            null
-        );
+        QueryShardContext queryShardContext = indexService.newQueryShardContext(randomInt(20), null, () -> {
+            throw new UnsupportedOperationException();
+        }, null);
         MultiMatchQuery parser = new MultiMatchQuery(queryShardContext);
         Map<String, Float> fieldNames = new HashMap<>();
         fieldNames.put("field", 1.0f);
diff --git a/server/src/test/java/org/opensearch/index/seqno/ReplicationTrackerTests.java b/server/src/test/java/org/opensearch/index/seqno/ReplicationTrackerTests.java
index 8ea64e71fb9dc..ee5307320cbfb 100644
--- a/server/src/test/java/org/opensearch/index/seqno/ReplicationTrackerTests.java
+++ b/server/src/test/java/org/opensearch/index/seqno/ReplicationTrackerTests.java
@@ -46,7 +46,10 @@
 import org.opensearch.common.settings.Settings;
 import org.opensearch.common.util.set.Sets;
 import org.opensearch.index.IndexSettings;
+import org.opensearch.index.SegmentReplicationShardStats;
 import org.opensearch.index.shard.ShardId;
+import org.opensearch.indices.replication.checkpoint.ReplicationCheckpoint;
+import org.opensearch.indices.replication.common.ReplicationType;
 import org.opensearch.test.IndexSettingsModule;
 
 import java.io.IOException;
@@ -72,6 +75,7 @@
 import java.util.stream.Stream;
 
 import static java.util.Collections.emptySet;
+import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_REPLICATION_TYPE;
 import static org.opensearch.index.seqno.SequenceNumbers.NO_OPS_PERFORMED;
 import static org.opensearch.index.seqno.SequenceNumbers.UNASSIGNED_SEQ_NO;
 import static org.hamcrest.Matchers.equalTo;
@@ -1770,6 +1774,78 @@ public void testUpdateAllocationIdsFromClusterManagerWithRemoteTranslogEnabled()
         assertFalse(tracker.pendingInSync.contains(newSyncingAllocationId.getId()));
     }
 
+    public void testSegmentReplicationCheckpointTracking() {
+        Settings settings = Settings.builder().put(SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT).build();
+        final long initialClusterStateVersion = randomNonNegativeLong();
+        final int numberOfActiveAllocationsIds = randomIntBetween(2, 16);
+        final int numberOfInitializingIds = randomIntBetween(2, 16);
+        final Tuple<Set<AllocationId>, Set<AllocationId>> activeAndInitializingAllocationIds = randomActiveAndInitializingAllocationIds(
+            numberOfActiveAllocationsIds,
+            numberOfInitializingIds
+        );
+        final Set<AllocationId> activeAllocationIds = activeAndInitializingAllocationIds.v1();
+        final Set<AllocationId> initializingIds = activeAndInitializingAllocationIds.v2();
+        AllocationId primaryId = activeAllocationIds.iterator().next();
+        IndexShardRoutingTable routingTable = routingTable(initializingIds, primaryId);
+        final ReplicationTracker tracker = newTracker(primaryId, settings);
+        tracker.updateFromClusterManager(initialClusterStateVersion, ids(activeAllocationIds), routingTable);
+        tracker.activatePrimaryMode(NO_OPS_PERFORMED);
+        assertThat(tracker.getReplicationGroup().getInSyncAllocationIds(), equalTo(ids(activeAllocationIds)));
+        assertThat(tracker.getReplicationGroup().getRoutingTable(), equalTo(routingTable));
+        assertTrue(activeAllocationIds.stream().allMatch(a -> tracker.getTrackedLocalCheckpointForShard(a.getId()).inSync));
+        // get insync ids, filter out the primary.
+        final Set<String> inSyncAllocationIds = tracker.getReplicationGroup()
+            .getInSyncAllocationIds()
+            .stream()
+            .filter(id -> tracker.shardAllocationId.equals(id) == false)
+            .collect(Collectors.toSet());
+
+        final ReplicationCheckpoint initialCheckpoint = new ReplicationCheckpoint(tracker.shardId(), 0L, 1, 1, 1L);
+        final ReplicationCheckpoint secondCheckpoint = new ReplicationCheckpoint(tracker.shardId(), 0L, 2, 2, 50L);
+        final ReplicationCheckpoint thirdCheckpoint = new ReplicationCheckpoint(tracker.shardId(), 0L, 2, 3, 100L);
+
+        tracker.setLatestReplicationCheckpoint(initialCheckpoint);
+        tracker.setLatestReplicationCheckpoint(secondCheckpoint);
+        tracker.setLatestReplicationCheckpoint(thirdCheckpoint);
+
+        Set<SegmentReplicationShardStats> groupStats = tracker.getSegmentReplicationStats();
+        assertEquals(inSyncAllocationIds.size(), groupStats.size());
+        for (SegmentReplicationShardStats shardStat : groupStats) {
+            assertEquals(3, shardStat.getCheckpointsBehindCount());
+            assertEquals(100L, shardStat.getBytesBehindCount());
+        }
+
+        // simulate replicas moved up to date.
+        final Map<String, ReplicationTracker.CheckpointState> checkpoints = tracker.checkpoints;
+        for (String id : inSyncAllocationIds) {
+            final ReplicationTracker.CheckpointState checkpointState = checkpoints.get(id);
+            assertEquals(3, checkpointState.checkpointTimers.size());
+            tracker.updateVisibleCheckpointForShard(id, initialCheckpoint);
+            assertEquals(2, checkpointState.checkpointTimers.size());
+        }
+
+        groupStats = tracker.getSegmentReplicationStats();
+        assertEquals(inSyncAllocationIds.size(), groupStats.size());
+        for (SegmentReplicationShardStats shardStat : groupStats) {
+            assertEquals(2, shardStat.getCheckpointsBehindCount());
+            assertEquals(99L, shardStat.getBytesBehindCount());
+        }
+
+        for (String id : inSyncAllocationIds) {
+            final ReplicationTracker.CheckpointState checkpointState = checkpoints.get(id);
+            assertEquals(2, checkpointState.checkpointTimers.size());
+            tracker.updateVisibleCheckpointForShard(id, thirdCheckpoint);
+            assertEquals(0, checkpointState.checkpointTimers.size());
+        }
+
+        groupStats = tracker.getSegmentReplicationStats();
+        assertEquals(inSyncAllocationIds.size(), groupStats.size());
+        for (SegmentReplicationShardStats shardStat : groupStats) {
+            assertEquals(0, shardStat.getCheckpointsBehindCount());
+            assertEquals(0L, shardStat.getBytesBehindCount());
+        }
+    }
+
     public void testPrimaryContextHandoffWithRemoteTranslogEnabled() throws IOException {
         Settings settings = Settings.builder().put("index.remote_store.translog.enabled", "true").build();
         final IndexSettings indexSettings = IndexSettingsModule.newIndexSettings("test", settings);
diff --git a/server/src/test/java/org/opensearch/index/shard/GlobalCheckpointListenersTests.java b/server/src/test/java/org/opensearch/index/shard/GlobalCheckpointListenersTests.java
index 28e29ec0d0249..1b7bdaf710de4 100644
--- a/server/src/test/java/org/opensearch/index/shard/GlobalCheckpointListenersTests.java
+++ b/server/src/test/java/org/opensearch/index/shard/GlobalCheckpointListenersTests.java
@@ -625,11 +625,9 @@ public void testFailingListenerAfterTimeout() throws InterruptedException {
         }).when(mockLogger).warn(any(String.class), any(RuntimeException.class));
         final GlobalCheckpointListeners globalCheckpointListeners = new GlobalCheckpointListeners(shardId, scheduler, mockLogger);
         final TimeValue timeout = TimeValue.timeValueMillis(randomIntBetween(1, 50));
-        globalCheckpointListeners.add(
-            NO_OPS_PERFORMED,
-            maybeMultipleInvocationProtectingListener((g, e) -> { throw new RuntimeException("failure"); }),
-            timeout
-        );
+        globalCheckpointListeners.add(NO_OPS_PERFORMED, maybeMultipleInvocationProtectingListener((g, e) -> {
+            throw new RuntimeException("failure");
+        }), timeout);
         latch.await();
         final ArgumentCaptor<String> message = ArgumentCaptor.forClass(String.class);
         final ArgumentCaptor<RuntimeException> t = ArgumentCaptor.forClass(RuntimeException.class);
diff --git a/server/src/test/java/org/opensearch/index/shard/IndexShardOperationPermitsTests.java b/server/src/test/java/org/opensearch/index/shard/IndexShardOperationPermitsTests.java
index 9d73fa3524a8c..6e130c1938b4f 100644
--- a/server/src/test/java/org/opensearch/index/shard/IndexShardOperationPermitsTests.java
+++ b/server/src/test/java/org/opensearch/index/shard/IndexShardOperationPermitsTests.java
@@ -226,18 +226,12 @@ public void testOperationsIfClosed() {
 
     public void testBlockIfClosed() {
         permits.close();
-        expectThrows(
-            IndexShardClosedException.class,
-            () -> permits.blockOperations(randomInt(10), TimeUnit.MINUTES, () -> { throw new IllegalArgumentException("fake error"); })
-        );
-        expectThrows(
-            IndexShardClosedException.class,
-            () -> permits.asyncBlockOperations(
-                wrap(() -> { throw new IllegalArgumentException("fake error"); }),
-                randomInt(10),
-                TimeUnit.MINUTES
-            )
-        );
+        expectThrows(IndexShardClosedException.class, () -> permits.blockOperations(randomInt(10), TimeUnit.MINUTES, () -> {
+            throw new IllegalArgumentException("fake error");
+        }));
+        expectThrows(IndexShardClosedException.class, () -> permits.asyncBlockOperations(wrap(() -> {
+            throw new IllegalArgumentException("fake error");
+        }), randomInt(10), TimeUnit.MINUTES));
     }
 
     public void testOperationsDelayedIfBlock() throws ExecutionException, InterruptedException, TimeoutException {
diff --git a/server/src/test/java/org/opensearch/index/shard/IndexShardTests.java b/server/src/test/java/org/opensearch/index/shard/IndexShardTests.java
index e9d22dfe4b4d6..4926b9dcd6f9b 100644
--- a/server/src/test/java/org/opensearch/index/shard/IndexShardTests.java
+++ b/server/src/test/java/org/opensearch/index/shard/IndexShardTests.java
@@ -2113,11 +2113,9 @@ public void testRelocatedSegRepError() throws IOException, InterruptedException
         IndexShardTestCase.updateRoutingEntry(shard, routing);
         ReplicationFailedException segRepException = expectThrows(
             ReplicationFailedException.class,
-            () -> shard.relocated(
-                routing.getTargetRelocatingShard().allocationId().getId(),
-                primaryContext -> {},
-                () -> { throw new ReplicationFailedException("Segment replication failed"); }
-            )
+            () -> shard.relocated(routing.getTargetRelocatingShard().allocationId().getId(), primaryContext -> {}, () -> {
+                throw new ReplicationFailedException("Segment replication failed");
+            })
         );
         assertTrue(segRepException.getMessage().equals("Segment replication failed"));
         closeShards(shard);
@@ -2900,11 +2898,9 @@ public void testReaderWrapperWorksWithGlobalOrdinals() throws IOException {
             new NoneCircuitBreakerService(),
             shard.mapperService()
         );
-        IndexFieldData.Global ifd = indexFieldDataService.getForField(
-            foo,
-            "test",
-            () -> { throw new UnsupportedOperationException("search lookup not available"); }
-        );
+        IndexFieldData.Global ifd = indexFieldDataService.getForField(foo, "test", () -> {
+            throw new UnsupportedOperationException("search lookup not available");
+        });
         FieldDataStats before = shard.fieldData().stats("foo");
         assertThat(before.getMemorySizeInBytes(), equalTo(0L));
         FieldDataStats after = null;
diff --git a/server/src/test/java/org/opensearch/index/shard/SearchOperationListenerTests.java b/server/src/test/java/org/opensearch/index/shard/SearchOperationListenerTests.java
index 8d89cc2383aeb..98f86758ea2ca 100644
--- a/server/src/test/java/org/opensearch/index/shard/SearchOperationListenerTests.java
+++ b/server/src/test/java/org/opensearch/index/shard/SearchOperationListenerTests.java
@@ -138,7 +138,9 @@ public void validateReaderContext(ReaderContext readerContext, TransportRequest
         SearchOperationListener throwingListener = (SearchOperationListener) Proxy.newProxyInstance(
             SearchOperationListener.class.getClassLoader(),
             new Class[] { SearchOperationListener.class },
-            (a, b, c) -> { throw new RuntimeException(); }
+            (a, b, c) -> {
+                throw new RuntimeException();
+            }
         );
         int throwingListeners = 0;
         final List<SearchOperationListener> indexingOperationListeners = new ArrayList<>(Arrays.asList(listener, listener));
diff --git a/server/src/test/java/org/opensearch/index/shard/SegmentReplicationIndexShardTests.java b/server/src/test/java/org/opensearch/index/shard/SegmentReplicationIndexShardTests.java
index d554af0ffc488..014a37249612b 100644
--- a/server/src/test/java/org/opensearch/index/shard/SegmentReplicationIndexShardTests.java
+++ b/server/src/test/java/org/opensearch/index/shard/SegmentReplicationIndexShardTests.java
@@ -8,7 +8,6 @@
 
 package org.opensearch.index.shard;
 
-import org.apache.lucene.index.IndexCommit;
 import org.apache.lucene.index.SegmentInfos;
 import org.junit.Assert;
 import org.opensearch.ExceptionsHelper;
@@ -155,7 +154,6 @@ public void testSegmentInfosAndReplicationCheckpointTuple() throws Exception {
     private void assertReplicationCheckpoint(IndexShard shard, SegmentInfos segmentInfos, ReplicationCheckpoint checkpoint)
         throws IOException {
         assertNotNull(segmentInfos);
-        assertEquals(checkpoint.getSeqNo(), shard.getEngine().getMaxSeqNoFromSegmentInfos(segmentInfos));
         assertEquals(checkpoint.getSegmentInfosVersion(), segmentInfos.getVersion());
         assertEquals(checkpoint.getSegmentsGen(), segmentInfos.getGeneration());
     }
@@ -259,7 +257,7 @@ public void testPublishCheckpointOnPrimaryMode() throws IOException {
         refreshListener.afterRefresh(true);
 
         // verify checkpoint is published
-        verify(mock, times(1)).publish(any());
+        verify(mock, times(1)).publish(any(), any());
         closeShards(shard);
     }
 
@@ -281,7 +279,7 @@ public void testPublishCheckpointAfterRelocationHandOff() throws IOException {
         refreshListener.afterRefresh(true);
 
         // verify checkpoint is not published
-        verify(mock, times(0)).publish(any());
+        verify(mock, times(0)).publish(any(), any());
         closeShards(shard);
     }
 
@@ -308,7 +306,7 @@ public void testRejectCheckpointOnShardRoutingPrimary() throws IOException {
         assertEquals(false, primaryShard.getReplicationTracker().isPrimaryMode());
         assertEquals(true, primaryShard.routingEntry().primary());
 
-        spy.onNewCheckpoint(new ReplicationCheckpoint(primaryShard.shardId(), 0L, 0L, 0L, 0L), spyShard);
+        spy.onNewCheckpoint(new ReplicationCheckpoint(primaryShard.shardId(), 0L, 0L, 0L), spyShard);
 
         // Verify that checkpoint is not processed as shard routing is primary.
         verify(spy, times(0)).startReplication(any(), any(), any());
@@ -570,21 +568,15 @@ public void testReplicaReceivesLowerGeneration() throws Exception {
             numDocs = randomIntBetween(numDocs + 1, numDocs + 10);
             shards.indexDocs(numDocs);
             flushShard(primary, false);
-            assertLatestCommitGen(4, primary);
             replicateSegments(primary, List.of(replica_1));
 
             assertEqualCommittedSegments(primary, replica_1);
-            assertLatestCommitGen(4, primary);
-            assertLatestCommitGen(5, replica_1);
-            assertLatestCommitGen(3, replica_2);
 
             shards.promoteReplicaToPrimary(replica_2).get();
             primary.close("demoted", false);
             primary.store().close();
             IndexShard oldPrimary = shards.addReplicaWithExistingPath(primary.shardPath(), primary.routingEntry().currentNodeId());
             shards.recoverReplica(oldPrimary);
-            assertLatestCommitGen(5, oldPrimary);
-            assertLatestCommitGen(5, replica_2);
 
             numDocs = randomIntBetween(numDocs + 1, numDocs + 10);
             shards.indexDocs(numDocs);
@@ -1024,8 +1016,6 @@ private void assertDocCounts(IndexShard indexShard, int expectedPersistedDocCoun
         // assigned seqNos start at 0, so assert max & local seqNos are 1 less than our persisted doc count.
         assertEquals(expectedPersistedDocCount - 1, indexShard.seqNoStats().getMaxSeqNo());
         assertEquals(expectedPersistedDocCount - 1, indexShard.seqNoStats().getLocalCheckpoint());
-        // processed cp should be 1 less than our searchable doc count.
-        assertEquals(expectedSearchableDocCount - 1, indexShard.getProcessedLocalCheckpoint());
     }
 
     private void resolveCheckpointInfoResponseListener(ActionListener<CheckpointInfoResponse> listener, IndexShard primary) {
@@ -1081,14 +1071,6 @@ private IndexShard failAndPromoteRandomReplica(ReplicationGroup shards) throws I
         return newPrimary;
     }
 
-    private void assertLatestCommitGen(long expected, IndexShard... shards) throws IOException {
-        for (IndexShard indexShard : shards) {
-            try (final GatedCloseable<IndexCommit> commit = indexShard.acquireLastIndexCommit(false)) {
-                assertEquals(expected, commit.get().getGeneration());
-            }
-        }
-    }
-
     private void assertEqualCommittedSegments(IndexShard primary, IndexShard... replicas) throws IOException {
         for (IndexShard replica : replicas) {
             final SegmentInfos replicaInfos = replica.store().readLastCommittedSegmentsInfo();
diff --git a/server/src/test/java/org/opensearch/index/shard/ShardPathTests.java b/server/src/test/java/org/opensearch/index/shard/ShardPathTests.java
index 443325b8716c0..e445d4b78de9d 100644
--- a/server/src/test/java/org/opensearch/index/shard/ShardPathTests.java
+++ b/server/src/test/java/org/opensearch/index/shard/ShardPathTests.java
@@ -148,7 +148,7 @@ public void testGetRootPaths() throws IOException {
     }
 
     public void testLoadFileCachePath() throws IOException {
-        Settings searchNodeSettings = Settings.builder().put("node.roles", "search").put(PATH_SHARED_DATA_SETTING.getKey(), "").build();
+        Settings searchNodeSettings = Settings.builder().put("node.roles", "search").build();
 
         try (NodeEnvironment env = newNodeEnvironment(searchNodeSettings)) {
             ShardId shardId = new ShardId("foo", "0xDEADBEEF", 0);
diff --git a/server/src/test/java/org/opensearch/index/similarity/ScriptedSimilarityTests.java b/server/src/test/java/org/opensearch/index/similarity/ScriptedSimilarityTests.java
index ef935ba64f1ca..f4282b8221c05 100644
--- a/server/src/test/java/org/opensearch/index/similarity/ScriptedSimilarityTests.java
+++ b/server/src/test/java/org/opensearch/index/similarity/ScriptedSimilarityTests.java
@@ -111,10 +111,9 @@ public double execute(
                 ) {
 
                     StackTraceElement[] stackTraceElements = Thread.currentThread().getStackTrace();
-                    if (Arrays.stream(stackTraceElements)
-                        .anyMatch(
-                            ste -> { return ste.getClassName().endsWith(".TermScorer") && ste.getMethodName().equals("score"); }
-                        ) == false) {
+                    if (Arrays.stream(stackTraceElements).anyMatch(ste -> {
+                        return ste.getClassName().endsWith(".TermScorer") && ste.getMethodName().equals("score");
+                    }) == false) {
                         // this might happen when computing max scores
                         return Float.MAX_VALUE;
                     }
@@ -210,10 +209,9 @@ public double execute(
                 ) {
 
                     StackTraceElement[] stackTraceElements = Thread.currentThread().getStackTrace();
-                    if (Arrays.stream(stackTraceElements)
-                        .anyMatch(
-                            ste -> { return ste.getClassName().endsWith(".TermScorer") && ste.getMethodName().equals("score"); }
-                        ) == false) {
+                    if (Arrays.stream(stackTraceElements).anyMatch(ste -> {
+                        return ste.getClassName().endsWith(".TermScorer") && ste.getMethodName().equals("score");
+                    }) == false) {
                         // this might happen when computing max scores
                         return Float.MAX_VALUE;
                     }
diff --git a/server/src/test/java/org/opensearch/index/store/RemoteDirectoryTests.java b/server/src/test/java/org/opensearch/index/store/RemoteDirectoryTests.java
index 97575248b4ad3..15f1585bd1477 100644
--- a/server/src/test/java/org/opensearch/index/store/RemoteDirectoryTests.java
+++ b/server/src/test/java/org/opensearch/index/store/RemoteDirectoryTests.java
@@ -15,7 +15,6 @@
 import org.opensearch.common.blobstore.BlobContainer;
 import org.opensearch.common.blobstore.BlobMetadata;
 import org.opensearch.common.blobstore.support.PlainBlobMetadata;
-import org.opensearch.common.collect.Set;
 import org.opensearch.test.OpenSearchTestCase;
 
 import java.io.IOException;
@@ -25,6 +24,7 @@
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.Set;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
diff --git a/server/src/test/java/org/opensearch/index/store/RemoteSegmentStoreDirectoryTests.java b/server/src/test/java/org/opensearch/index/store/RemoteSegmentStoreDirectoryTests.java
index 8b7a2e8e06207..956279c3ea048 100644
--- a/server/src/test/java/org/opensearch/index/store/RemoteSegmentStoreDirectoryTests.java
+++ b/server/src/test/java/org/opensearch/index/store/RemoteSegmentStoreDirectoryTests.java
@@ -21,7 +21,6 @@
 import org.junit.Before;
 import org.opensearch.common.UUIDs;
 import org.opensearch.common.bytes.BytesReference;
-import org.opensearch.common.collect.Set;
 import org.opensearch.common.io.stream.BytesStreamOutput;
 import org.opensearch.common.lucene.store.ByteArrayIndexInput;
 import org.opensearch.index.store.remote.metadata.RemoteSegmentMetadata;
@@ -34,6 +33,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 import static org.mockito.Mockito.any;
 import static org.mockito.Mockito.doReturn;
@@ -162,7 +162,7 @@ private Map<String, String> getDummyMetadata(String prefix, int commitGeneration
      * Prepares metadata file bytes with header and footer
      * @param segmentFilesMap: actual metadata content
      * @return ByteArrayIndexInput: metadata file bytes with header and footer
-     * @throws IOException
+     * @throws IOException IOException
      */
     private ByteArrayIndexInput createMetadataFileBytes(Map<String, String> segmentFilesMap) throws IOException {
         BytesStreamOutput output = new BytesStreamOutput();
diff --git a/server/src/test/java/org/opensearch/index/store/remote/filecache/FileCacheTests.java b/server/src/test/java/org/opensearch/index/store/remote/filecache/FileCacheTests.java
index 997f8702c836d..72ac9837537e1 100644
--- a/server/src/test/java/org/opensearch/index/store/remote/filecache/FileCacheTests.java
+++ b/server/src/test/java/org/opensearch/index/store/remote/filecache/FileCacheTests.java
@@ -10,15 +10,16 @@
 
 import org.apache.lucene.store.IndexInput;
 import org.junit.Before;
+import org.opensearch.common.SuppressForbidden;
+import org.opensearch.env.NodeEnvironment;
+import org.opensearch.index.store.remote.directory.RemoteSnapshotDirectoryFactory;
 import org.opensearch.index.store.remote.utils.cache.CacheUsage;
 import org.opensearch.test.OpenSearchTestCase;
 
 import java.io.IOException;
+import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.ArrayList;
-import java.util.HashMap;
 import java.util.List;
-import java.util.Map;
 
 public class FileCacheTests extends OpenSearchTestCase {
     // need concurrency level to be static to make these tests more deterministic because capacity per segment is dependent on
@@ -35,14 +36,27 @@ public void init() throws Exception {
         path = createTempDir("FileCacheTests");
     }
 
-    private FileCache createFileCache(long capaticy) {
-        return FileCacheFactory.createConcurrentLRUFileCache(capaticy, CONCURRENCY_LEVEL);
+    private FileCache createFileCache(long capacity) {
+        return FileCacheFactory.createConcurrentLRUFileCache(capacity, CONCURRENCY_LEVEL);
     }
 
     private Path createPath(String middle) {
         return path.resolve(middle).resolve(FAKE_PATH_SUFFIX);
     }
 
+    @SuppressForbidden(reason = "creating a test file for cache")
+    private void createFile(String nodeId, String indexName, String shardId, String fileName) throws IOException {
+        Path folderPath = path.resolve(NodeEnvironment.CACHE_FOLDER)
+            .resolve(nodeId)
+            .resolve(indexName)
+            .resolve(shardId)
+            .resolve(RemoteSnapshotDirectoryFactory.LOCAL_STORE_LOCATION);
+        Path filePath = folderPath.resolve(fileName);
+        Files.createDirectories(folderPath);
+        Files.createFile(filePath);
+        Files.write(filePath, "test-data".getBytes());
+    }
+
     public void testCreateCacheWithSmallSegments() {
         assertThrows(IllegalStateException.class, () -> { FileCacheFactory.createConcurrentLRUFileCache(1000, CONCURRENCY_LEVEL); });
     }
@@ -73,36 +87,23 @@ public void testPutThrowException() {
         });
     }
 
-    public void testComputeIfPresent() {
+    public void testCompute() {
         FileCache fileCache = createFileCache(GIGA_BYTES);
         Path path = createPath("0");
         fileCache.put(path, new FakeIndexInput(8 * MEGA_BYTES));
         fileCache.incRef(path);
-        fileCache.computeIfPresent(path, (p, i) -> null);
+        fileCache.compute(path, (p, i) -> null);
         // item will be removed
         assertEquals(fileCache.size(), 0);
     }
 
-    public void testComputeIfPresentThrowException() {
+    public void testComputeThrowException() {
         assertThrows(NullPointerException.class, () -> {
             FileCache fileCache = createFileCache(GIGA_BYTES);
-            fileCache.computeIfPresent(null, null);
+            fileCache.compute(null, null);
         });
     }
 
-    public void testPutAll() {
-        FileCache fileCache = createFileCache(GIGA_BYTES);
-        Map<Path, CachedIndexInput> blockMaps = new HashMap<>();
-        for (int i = 0; i < 4; i++) {
-            blockMaps.put(createPath(Integer.toString(i)), new FakeIndexInput(8 * MEGA_BYTES));
-        }
-        fileCache.putAll(blockMaps);
-        // verify all blocks are put into file cache
-        for (int i = 0; i < 4; i++) {
-            assertNotNull(fileCache.get(createPath(Integer.toString(i))));
-        }
-    }
-
     public void testRemove() {
         FileCache fileCache = createFileCache(GIGA_BYTES);
         for (int i = 0; i < 4; i++) {
@@ -124,33 +125,21 @@ public void testRemoveThrowException() {
         });
     }
 
-    public void testRemoveAll() {
-        FileCache fileCache = createFileCache(GIGA_BYTES);
-        List<Path> blockPathList = new ArrayList<>();
-        for (int i = 0; i < 4; i++) {
-            Path blockPath = createPath(Integer.toString(i));
-            fileCache.put(blockPath, new FakeIndexInput(8 * MEGA_BYTES));
-            blockPathList.add(blockPath);
-        }
-        fileCache.removeAll(blockPathList);
-        assertEquals(fileCache.size(), 0);
-    }
-
     public void testIncDecRef() {
         FileCache fileCache = createFileCache(GIGA_BYTES);
         for (int i = 0; i < 4; i++) {
             fileCache.put(createPath(Integer.toString(i)), new FakeIndexInput(8 * MEGA_BYTES));
-            fileCache.incRef(createPath(Integer.toString(i)));
         }
 
         // try to evict previous IndexInput
         for (int i = 1000; i < 3000; i++) {
-            fileCache.put(createPath(Integer.toString(i)), new FakeIndexInput(8 * MEGA_BYTES));
+            putAndDecRef(fileCache, i, 8 * MEGA_BYTES);
         }
 
         // IndexInput with refcount greater than 0 will not be evicted
         for (int i = 0; i < 4; i++) {
             assertNotNull(fileCache.get(createPath(Integer.toString(i))));
+            fileCache.decRef(createPath(Integer.toString(i)));
         }
 
         // decrease ref
@@ -160,7 +149,7 @@ public void testIncDecRef() {
 
         // try to evict previous IndexInput again
         for (int i = 3000; i < 5000; i++) {
-            fileCache.put(createPath(Integer.toString(i)), new FakeIndexInput(8 * MEGA_BYTES));
+            putAndDecRef(fileCache, i, 8 * MEGA_BYTES);
         }
 
         for (int i = 0; i < 4; i++) {
@@ -201,7 +190,7 @@ public void testSize() {
     public void testPrune() {
         FileCache fileCache = createFileCache(GIGA_BYTES);
         for (int i = 0; i < 4; i++) {
-            fileCache.put(createPath(Integer.toString(i)), new FakeIndexInput(8 * MEGA_BYTES));
+            putAndDecRef(fileCache, i, 8 * MEGA_BYTES);
         }
         // before prune
         assertEquals(fileCache.size(), 4);
@@ -212,11 +201,10 @@ public void testPrune() {
     }
 
     public void testUsage() {
-        // edge case, all Indexinput will be evicted as soon as they are put into file cache
-        FileCache fileCache = createFileCache(MEGA_BYTES);
-        fileCache.put(createPath("0"), new FakeIndexInput(8 * MEGA_BYTES));
+        FileCache fileCache = FileCacheFactory.createConcurrentLRUFileCache(16 * MEGA_BYTES, 1);
+        putAndDecRef(fileCache, 0, 16 * MEGA_BYTES);
 
-        CacheUsage expectedCacheUsage = new CacheUsage(0, 0);
+        CacheUsage expectedCacheUsage = new CacheUsage(16 * MEGA_BYTES, 0);
         CacheUsage realCacheUsage = fileCache.usage();
         assertEquals(expectedCacheUsage.activeUsage(), realCacheUsage.activeUsage());
         assertEquals(expectedCacheUsage.usage(), realCacheUsage.usage());
@@ -238,13 +226,31 @@ public void testStats() {
 
         // do some eviction here
         for (int i = 0; i < 2000; i++) {
-            fileCache.put(createPath(Integer.toString(i)), new FakeIndexInput(8 * MEGA_BYTES));
+            putAndDecRef(fileCache, i, 8 * MEGA_BYTES);
         }
         assertTrue(fileCache.stats().evictionCount() > 0);
         assertTrue(fileCache.stats().evictionWeight() > 0);
 
     }
 
+    public void testCacheRestore() throws IOException {
+        String nodeId = "0";
+        String indexName = "test-index";
+        String shardId = "0";
+        createFile(nodeId, indexName, shardId, "test.0");
+        FileCache fileCache = createFileCache(GIGA_BYTES);
+        assertEquals(0, fileCache.usage().usage());
+        Path fileCachePath = path.resolve(NodeEnvironment.CACHE_FOLDER).resolve(nodeId).resolve(indexName).resolve(shardId);
+        fileCache.restoreFromDirectory(List.of(fileCachePath));
+        assertTrue(fileCache.usage().usage() > 0);
+    }
+
+    private void putAndDecRef(FileCache cache, int path, long indexInputSize) {
+        final Path key = createPath(Integer.toString(path));
+        cache.put(key, new FakeIndexInput(indexInputSize));
+        cache.decRef(key);
+    }
+
     final class FakeIndexInput extends CachedIndexInput {
 
         private final long length;
diff --git a/server/src/test/java/org/opensearch/index/store/remote/utils/ConcurrentInvocationLinearizerTests.java b/server/src/test/java/org/opensearch/index/store/remote/utils/ConcurrentInvocationLinearizerTests.java
deleted file mode 100644
index 5538b77184604..0000000000000
--- a/server/src/test/java/org/opensearch/index/store/remote/utils/ConcurrentInvocationLinearizerTests.java
+++ /dev/null
@@ -1,122 +0,0 @@
-/*
- * SPDX-License-Identifier: Apache-2.0
- *
- * The OpenSearch Contributors require contributions made to
- * this file be licensed under the Apache-2.0 license or a
- * compatible open source license.
- */
-
-package org.opensearch.index.store.remote.utils;
-
-import org.hamcrest.MatcherAssert;
-import org.junit.After;
-import org.junit.Before;
-import org.opensearch.test.OpenSearchTestCase;
-
-import java.io.IOException;
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-import java.util.concurrent.Future;
-
-import static org.hamcrest.Matchers.anEmptyMap;
-import static org.hamcrest.Matchers.equalTo;
-import static org.hamcrest.Matchers.instanceOf;
-import static org.hamcrest.Matchers.is;
-
-public class ConcurrentInvocationLinearizerTests extends OpenSearchTestCase {
-    private ExecutorService executorService;
-
-    @Before
-    public void setup() {
-        executorService = Executors.newSingleThreadExecutor();
-    }
-
-    public void testLinearizeShouldNotInvokeMethodMoreThanOnce() throws Exception {
-        final ConcurrentInvocationLinearizer<String, String> invocationLinearizer = new ConcurrentInvocationLinearizer<>();
-        final CountDownLatch startLatch = new CountDownLatch(1);
-        final CountDownLatch finishLatch = new CountDownLatch(1);
-
-        final Future<Future<String>> first = executorService.submit(() -> invocationLinearizer.linearizeInternal("input", s -> {
-            startLatch.countDown();
-            try {
-                finishLatch.await();
-            } catch (InterruptedException e) {
-                throw new AssertionError(e);
-            }
-            return "expected";
-        }));
-
-        startLatch.await(); // Wait for first caller to start work
-        final Future<String> second = invocationLinearizer.linearizeInternal("input", s -> { throw new AssertionError(); });
-        final Future<String> third = invocationLinearizer.linearizeInternal("input", s -> { throw new AssertionError(); });
-        finishLatch.countDown(); // Unblock first caller
-        MatcherAssert.assertThat(first.get().get(), equalTo("expected"));
-        MatcherAssert.assertThat(second.get(), equalTo("expected"));
-        MatcherAssert.assertThat(third.get(), equalTo("expected"));
-        MatcherAssert.assertThat(invocationLinearizer.getInvokeOnceCache(), is(anEmptyMap()));
-    }
-
-    public void testLinearizeSharesFailures() throws Exception {
-        final ConcurrentInvocationLinearizer<String, String> invocationLinearizer = new ConcurrentInvocationLinearizer<>();
-        final CountDownLatch startLatch = new CountDownLatch(1);
-        final CountDownLatch finishLatch = new CountDownLatch(1);
-
-        final Future<Future<String>> first = executorService.submit(() -> invocationLinearizer.linearizeInternal("input", s -> {
-            startLatch.countDown();
-            try {
-                finishLatch.await();
-            } catch (InterruptedException e) {
-                throw new AssertionError(e);
-            }
-            throw new IOException("io exception");
-        }));
-
-        startLatch.await(); // Wait for first caller to start work
-        final Future<String> second = invocationLinearizer.linearizeInternal("input", s -> { throw new AssertionError(); });
-        finishLatch.countDown(); // Unblock first caller
-        final ExecutionException e1 = assertThrows(ExecutionException.class, () -> first.get().get());
-        MatcherAssert.assertThat(e1.getCause(), instanceOf(IOException.class));
-        final ExecutionException e2 = assertThrows(ExecutionException.class, second::get);
-        MatcherAssert.assertThat(e2.getCause(), instanceOf(IOException.class));
-        MatcherAssert.assertThat(invocationLinearizer.getInvokeOnceCache(), is(anEmptyMap()));
-    }
-
-    public void testLinearizeShouldLeaveCacheEmptyEvenWhenFutureFail() {
-        ConcurrentInvocationLinearizer<String, String> invocationLinearizer = new ConcurrentInvocationLinearizer<>();
-        assertThrows(
-            RuntimeException.class,
-            () -> invocationLinearizer.linearize("input", s -> { throw new RuntimeException("exception"); })
-        );
-        MatcherAssert.assertThat("Expected nothing to be cached on failure", invocationLinearizer.getInvokeOnceCache(), is(anEmptyMap()));
-    }
-
-    public void testExceptionHandling() {
-        final ConcurrentInvocationLinearizer<String, String> invocationLinearizer = new ConcurrentInvocationLinearizer<>();
-        assertThrows(
-            RuntimeException.class,
-            () -> invocationLinearizer.linearize("input", s -> { throw new RuntimeException("exception"); })
-        );
-        assertThrows(IOException.class, () -> invocationLinearizer.linearize("input", s -> { throw new IOException("exception"); }));
-        assertThrows(AssertionError.class, () -> invocationLinearizer.linearize("input", s -> { throw new AssertionError("exception"); }));
-        final RuntimeException e = assertThrows(
-            RuntimeException.class,
-            () -> invocationLinearizer.linearize("input", s -> { throw sneakyThrow(new TestCheckedException()); })
-        );
-        MatcherAssert.assertThat(e.getCause(), instanceOf(TestCheckedException.class));
-    }
-
-    @After
-    public void cleanUp() {
-        executorService.shutdownNow();
-        terminate(executorService);
-    }
-
-    // Some unholy hackery with generics to trick the compiler into throwing an undeclared checked exception
-    private static <E extends Throwable> E sneakyThrow(Throwable e) throws E {
-        throw (E) e;
-    }
-
-    private static class TestCheckedException extends Exception {}
-}
diff --git a/server/src/test/java/org/opensearch/index/store/remote/utils/TransferManagerTests.java b/server/src/test/java/org/opensearch/index/store/remote/utils/TransferManagerTests.java
index 4e607cb587cc6..f3049c504f295 100644
--- a/server/src/test/java/org/opensearch/index/store/remote/utils/TransferManagerTests.java
+++ b/server/src/test/java/org/opensearch/index/store/remote/utils/TransferManagerTests.java
@@ -32,12 +32,17 @@
 import com.carrotsearch.randomizedtesting.annotations.ThreadLeakFilters;
 
 import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.greaterThan;
+import static org.mockito.ArgumentMatchers.anyLong;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.mock;
 
 @ThreadLeakFilters(filters = CleanerDaemonThreadLeakFilter.class)
 public class TransferManagerTests extends OpenSearchTestCase {
-    private final FileCache fileCache = FileCacheFactory.createConcurrentLRUFileCache(1024 * 1024, 8);
+    private static final int EIGHT_MB = 1024 * 1024 * 8;
+    private final FileCache fileCache = FileCacheFactory.createConcurrentLRUFileCache(EIGHT_MB * 2, 1);
     private MMapDirectory directory;
     private BlobContainer blobContainer;
     private TransferManager transferManager;
@@ -47,7 +52,7 @@ public void setUp() throws Exception {
         super.setUp();
         directory = new MMapDirectory(createTempDir(), SimpleFSLockFactory.INSTANCE);
         blobContainer = mock(BlobContainer.class);
-        doAnswer(i -> new ByteArrayInputStream(new byte[] { 0, 1, 2, 3, 4, 5, 6, 7 })).when(blobContainer).readBlob("blob", 0, 8);
+        doAnswer(i -> new ByteArrayInputStream(createData())).when(blobContainer).readBlob(eq("blob"), anyLong(), anyLong());
         transferManager = new TransferManager(blobContainer, fileCache);
     }
 
@@ -56,20 +61,29 @@ public void tearDown() throws Exception {
         super.tearDown();
     }
 
+    private static byte[] createData() {
+        final byte[] data = new byte[EIGHT_MB];
+        data[EIGHT_MB - 1] = 7;
+        return data;
+    }
+
     public void testSingleAccess() throws Exception {
-        try (IndexInput i = fetchBlob()) {
-            i.seek(7);
-            MatcherAssert.assertThat(i.readByte(), equalTo((byte) 7));
+        try (IndexInput i = fetchBlobWithName("file")) {
+            assertIndexInputIsFunctional(i);
+            MatcherAssert.assertThat(fileCache.usage().activeUsage(), equalTo((long) EIGHT_MB));
         }
+        MatcherAssert.assertThat(fileCache.usage().activeUsage(), equalTo(0L));
+        MatcherAssert.assertThat(fileCache.usage().usage(), equalTo((long) EIGHT_MB));
     }
 
     public void testConcurrentAccess() throws Exception {
         // Kick off multiple threads that all concurrently request the same resource
+        final String blobname = "file";
         final ExecutorService testRunner = Executors.newFixedThreadPool(8);
         try {
             final List<Future<IndexInput>> futures = new ArrayList<>();
             for (int i = 0; i < 8; i++) {
-                futures.add(testRunner.submit(this::fetchBlob));
+                futures.add(testRunner.submit(() -> fetchBlobWithName(blobname)));
             }
             // Wait for all threads to complete
             for (Future<IndexInput> future : futures) {
@@ -80,19 +94,92 @@ public void testConcurrentAccess() throws Exception {
             // result in EOFExceptions and/or NPEs.
             for (Future<IndexInput> future : futures) {
                 try (IndexInput i = future.get()) {
-                    i.seek(7);
-                    MatcherAssert.assertThat(i.readByte(), equalTo((byte) 7));
+                    assertIndexInputIsFunctional(i);
                 }
             }
         } finally {
-            testRunner.shutdown();
-            assertTrue(testRunner.awaitTermination(1, TimeUnit.SECONDS));
+            assertTrue(terminate(testRunner));
+        }
+    }
+
+    public void testFetchBlobWithConcurrentCacheEvictions() throws Exception {
+        // Submit 256 tasks to an executor with 16 threads that will each randomly
+        // request one of eight blobs. Given that the cache can only hold two
+        // blobs this will lead to a huge amount of contention and thrashing.
+        final ExecutorService testRunner = Executors.newFixedThreadPool(16);
+        try {
+            final List<Future<?>> futures = new ArrayList<>();
+            for (int i = 0; i < 256; i++) {
+                // request an index input and immediately close it
+                final String blobname = "blob-" + randomIntBetween(0, 7);
+                futures.add(testRunner.submit(() -> {
+                    try {
+                        try (IndexInput indexInput = fetchBlobWithName(blobname)) {
+                            assertIndexInputIsFunctional(indexInput);
+                        }
+                    } catch (Exception e) {
+                        throw new AssertionError(e);
+                    }
+                }));
+            }
+            // Wait for all threads to complete
+            for (Future<?> future : futures) {
+                future.get(10, TimeUnit.SECONDS);
+            }
+        } finally {
+            assertTrue(terminate(testRunner));
         }
+        MatcherAssert.assertThat("Expected many evictions to happen", fileCache.stats().evictionCount(), greaterThan(0L));
     }
 
-    private IndexInput fetchBlob() throws InterruptedException, IOException {
+    public void testUsageExceedsCapacity() throws Exception {
+        // Fetch resources that exceed the configured capacity of the cache and assert that the
+        // returned IndexInputs are still functional.
+        try (IndexInput i1 = fetchBlobWithName("1"); IndexInput i2 = fetchBlobWithName("2"); IndexInput i3 = fetchBlobWithName("3")) {
+            assertIndexInputIsFunctional(i1);
+            assertIndexInputIsFunctional(i2);
+            assertIndexInputIsFunctional(i3);
+            MatcherAssert.assertThat(fileCache.usage().activeUsage(), equalTo((long) EIGHT_MB * 3));
+            MatcherAssert.assertThat(fileCache.usage().usage(), equalTo((long) EIGHT_MB * 3));
+        }
+        MatcherAssert.assertThat(fileCache.usage().activeUsage(), equalTo(0L));
+        MatcherAssert.assertThat(fileCache.usage().usage(), equalTo((long) EIGHT_MB * 3));
+        // Fetch another resource which will trigger an eviction
+        try (IndexInput i1 = fetchBlobWithName("1")) {
+            assertIndexInputIsFunctional(i1);
+            MatcherAssert.assertThat(fileCache.usage().activeUsage(), equalTo((long) EIGHT_MB));
+            MatcherAssert.assertThat(fileCache.usage().usage(), equalTo((long) EIGHT_MB));
+        }
+        MatcherAssert.assertThat(fileCache.usage().activeUsage(), equalTo(0L));
+        MatcherAssert.assertThat(fileCache.usage().usage(), equalTo((long) EIGHT_MB));
+    }
+
+    public void testDownloadFails() throws Exception {
+        doThrow(new IOException("Expected test exception")).when(blobContainer).readBlob(eq("failure-blob"), anyLong(), anyLong());
+        expectThrows(
+            IOException.class,
+            () -> transferManager.fetchBlob(
+                BlobFetchRequest.builder()
+                    .blobName("failure-blob")
+                    .position(0)
+                    .fileName("file")
+                    .directory(directory)
+                    .length(EIGHT_MB)
+                    .build()
+            )
+        );
+        MatcherAssert.assertThat(fileCache.usage().activeUsage(), equalTo(0L));
+        MatcherAssert.assertThat(fileCache.usage().usage(), equalTo(0L));
+    }
+
+    private IndexInput fetchBlobWithName(String blobname) throws IOException {
         return transferManager.fetchBlob(
-            BlobFetchRequest.builder().blobName("blob").position(0).fileName("file").directory(directory).length(8).build()
+            BlobFetchRequest.builder().blobName("blob").position(0).fileName(blobname).directory(directory).length(EIGHT_MB).build()
         );
     }
+
+    private static void assertIndexInputIsFunctional(IndexInput indexInput) throws IOException {
+        indexInput.seek(EIGHT_MB - 1);
+        MatcherAssert.assertThat(indexInput.readByte(), equalTo((byte) 7));
+    }
 }
diff --git a/server/src/test/java/org/opensearch/index/store/remote/utils/cache/LRUCacheTests.java b/server/src/test/java/org/opensearch/index/store/remote/utils/cache/LRUCacheTests.java
new file mode 100644
index 0000000000000..47cb8000b6c83
--- /dev/null
+++ b/server/src/test/java/org/opensearch/index/store/remote/utils/cache/LRUCacheTests.java
@@ -0,0 +1,15 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.index.store.remote.utils.cache;
+
+public class LRUCacheTests extends RefCountedCacheTestCase {
+    public LRUCacheTests() {
+        super(new LRUCache<>(CAPACITY, n -> {}, value -> value));
+    }
+}
diff --git a/server/src/test/java/org/opensearch/index/store/remote/utils/cache/RefCountedCacheTestCase.java b/server/src/test/java/org/opensearch/index/store/remote/utils/cache/RefCountedCacheTestCase.java
new file mode 100644
index 0000000000000..59657eebc4480
--- /dev/null
+++ b/server/src/test/java/org/opensearch/index/store/remote/utils/cache/RefCountedCacheTestCase.java
@@ -0,0 +1,203 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.index.store.remote.utils.cache;
+
+import org.opensearch.test.OpenSearchTestCase;
+
+abstract class RefCountedCacheTestCase extends OpenSearchTestCase {
+    static final int CAPACITY = 100;
+
+    private final RefCountedCache<String, Long> refCountedCache;
+
+    protected RefCountedCacheTestCase(RefCountedCache<String, Long> refCountedCache) {
+        this.refCountedCache = refCountedCache;
+    }
+
+    public void testBasicGetAndPutAndRemove() {
+        assertNull(refCountedCache.get("1"));
+        refCountedCache.put("1", 10L);
+        assertEquals(10L, (long) refCountedCache.get("1"));
+        refCountedCache.remove("1");
+        assertNull(refCountedCache.get("1"));
+    }
+
+    public void testUsageWithIncrementAndDecrement() {
+        refCountedCache.put("1", 10L);
+        assertEquals(10L, refCountedCache.usage().usage());
+        assertEquals(10L, refCountedCache.usage().activeUsage());
+
+        refCountedCache.decRef("1");
+        assertEquals(10L, refCountedCache.usage().usage());
+        assertEquals(0L, refCountedCache.usage().activeUsage());
+
+        refCountedCache.incRef("1");
+        assertEquals(10L, refCountedCache.usage().usage());
+        assertEquals(10L, refCountedCache.usage().activeUsage());
+    }
+
+    public void testEviction() {
+        for (int i = 1; i <= 5; i++) {
+            final String key = Integer.toString(i);
+            refCountedCache.put(key, 25L);
+            refCountedCache.decRef(key);
+        }
+        assertNull(refCountedCache.get("1"));
+        assertNull(refCountedCache.get("2"));
+        assertNotNull(refCountedCache.get("3"));
+        assertNotNull(refCountedCache.get("4"));
+        assertNotNull(refCountedCache.get("5"));
+
+        assertEquals(75L, refCountedCache.usage().usage());
+        assertEquals(75L, refCountedCache.usage().activeUsage());
+    }
+
+    public void testComputeRemoveWhenExists() {
+        refCountedCache.put("1", 25L);
+        refCountedCache.decRef("1");
+        assertEquals(0, refCountedCache.usage().activeUsage());
+        assertEquals(25L, refCountedCache.usage().usage());
+
+        assertNull(refCountedCache.compute("1", (k, v) -> null));
+        assertNull(refCountedCache.get("1"));
+        assertEquals(0, refCountedCache.usage().activeUsage());
+        assertEquals(0L, refCountedCache.usage().usage());
+    }
+
+    public void testComputeRemoveWhenNotExists() {
+        assertUsage(0, 0);
+        assertNull(refCountedCache.compute("1", (k, v) -> null));
+        assertNull(refCountedCache.get("1"));
+        assertUsage(0, 0);
+    }
+
+    public void testComputeRemapExists() {
+        assertUsage(0, 0);
+        refCountedCache.put("1", 25L);
+        refCountedCache.decRef("1");
+        assertUsage(25, 0);
+
+        final long newValue = refCountedCache.compute("1", (k, v) -> v + 5);
+        assertEquals(30L, newValue);
+        assertUsage(30, 30);
+
+        refCountedCache.decRef("1");
+        assertUsage(30, 0);
+
+        assertEquals(30L, (long) refCountedCache.get("1"));
+    }
+
+    public void testComputeRemapNotExists() {
+        assertUsage(0, 0);
+        final long newValue = refCountedCache.compute("1", (k, v) -> 30L);
+        assertEquals(30L, newValue);
+        assertUsage(30, 30);
+
+        refCountedCache.decRef("1");
+        assertUsage(30, 0);
+
+        assertEquals(30L, (long) refCountedCache.get("1"));
+    }
+
+    public void testActiveUsageGreaterThanCapacity() {
+        for (int i = 1; i <= 5; i++) {
+            final String key = Integer.toString(i);
+            refCountedCache.put(key, 25L);
+        }
+        assertEquals(125L, refCountedCache.usage().usage());
+        assertEquals(125L, refCountedCache.usage().activeUsage());
+    }
+
+    public void testReferenceCountingItemsThatDoNotExist() {
+        assertNull(refCountedCache.get("1"));
+        assertUsage(0, 0);
+        refCountedCache.incRef("1");
+        assertNull(refCountedCache.get("1"));
+        assertUsage(0, 0);
+        refCountedCache.decRef("1");
+        assertNull(refCountedCache.get("1"));
+        assertEquals(0L, refCountedCache.usage().usage());
+        assertEquals(0L, refCountedCache.usage().activeUsage());
+    }
+
+    public void testPrune() {
+        refCountedCache.put("1", 10L);
+        refCountedCache.decRef("1");
+        refCountedCache.put("2", 10L);
+        refCountedCache.decRef("2");
+        refCountedCache.put("3", 10L);
+
+        assertEquals(20L, refCountedCache.prune());
+        assertNull(refCountedCache.get("1"));
+        assertNull(refCountedCache.get("2"));
+        assertEquals(10L, (long) refCountedCache.get("3"));
+    }
+
+    public void testStats() {
+        assertEquals(0, refCountedCache.stats().hitCount());
+        refCountedCache.put("1", 1L);
+        refCountedCache.get("1");
+        assertEquals(1, refCountedCache.stats().hitCount());
+
+        assertEquals(0, refCountedCache.stats().replaceCount());
+        refCountedCache.put("1", 2L);
+        assertEquals(1, refCountedCache.stats().replaceCount());
+        assertEquals(1, refCountedCache.stats().hitCount());
+
+        assertEquals(0, refCountedCache.stats().evictionCount());
+        refCountedCache.put("2", 80L);
+        refCountedCache.decRef("2");
+        refCountedCache.put("3", 80L);
+        assertEquals(1, refCountedCache.stats().evictionCount());
+
+        assertEquals(0, refCountedCache.stats().missCount());
+        assertNull(refCountedCache.get("2"));
+        assertEquals(1, refCountedCache.stats().missCount());
+
+        assertEquals(0, refCountedCache.stats().removeCount());
+        refCountedCache.remove("3");
+        assertEquals(1, refCountedCache.stats().removeCount());
+    }
+
+    public void testComputeStats() {
+        refCountedCache.compute("1", (k, v) -> null);
+        assertEquals(0, refCountedCache.stats().missCount());
+        assertEquals(0, refCountedCache.stats().hitCount());
+        assertEquals(0, refCountedCache.stats().replaceCount());
+        assertEquals(0, refCountedCache.stats().removeCount());
+
+        refCountedCache.compute("1", (k, v) -> 10L);
+        assertEquals(1, refCountedCache.stats().missCount());
+        assertEquals(0, refCountedCache.stats().hitCount());
+        assertEquals(0, refCountedCache.stats().replaceCount());
+        assertEquals(0, refCountedCache.stats().removeCount());
+
+        refCountedCache.compute("1", (k, v) -> 10L);
+        assertEquals(1, refCountedCache.stats().missCount());
+        assertEquals(1, refCountedCache.stats().hitCount());
+        assertEquals(0, refCountedCache.stats().replaceCount());
+        assertEquals(0, refCountedCache.stats().removeCount());
+
+        refCountedCache.compute("1", (k, v) -> 20L);
+        assertEquals(1, refCountedCache.stats().missCount());
+        assertEquals(2, refCountedCache.stats().hitCount());
+        assertEquals(1, refCountedCache.stats().replaceCount());
+        assertEquals(0, refCountedCache.stats().removeCount());
+
+        refCountedCache.compute("1", (k, v) -> null);
+        assertEquals(1, refCountedCache.stats().missCount());
+        assertEquals(2, refCountedCache.stats().hitCount());
+        assertEquals(1, refCountedCache.stats().replaceCount());
+        assertEquals(1, refCountedCache.stats().removeCount());
+    }
+
+    private void assertUsage(long usage, long activeUsage) {
+        assertEquals(usage, refCountedCache.usage().usage());
+        assertEquals(activeUsage, refCountedCache.usage().activeUsage());
+    }
+}
diff --git a/server/src/test/java/org/opensearch/index/store/remote/utils/cache/RefCountedCacheTests.java b/server/src/test/java/org/opensearch/index/store/remote/utils/cache/RefCountedCacheTests.java
deleted file mode 100644
index 044e1e99627c0..0000000000000
--- a/server/src/test/java/org/opensearch/index/store/remote/utils/cache/RefCountedCacheTests.java
+++ /dev/null
@@ -1,130 +0,0 @@
-/*
- * SPDX-License-Identifier: Apache-2.0
- *
- * The OpenSearch Contributors require contributions made to
- * this file be licensed under the Apache-2.0 license or a
- * compatible open source license.
- */
-
-package org.opensearch.index.store.remote.utils.cache;
-
-import org.junit.Before;
-import org.mockito.Mockito;
-import org.opensearch.common.cache.RemovalListener;
-import org.opensearch.test.OpenSearchTestCase;
-
-import java.util.Arrays;
-import java.util.HashMap;
-import java.util.Map;
-
-public class RefCountedCacheTests extends OpenSearchTestCase {
-    private static final long SIZE = 100;
-    private RemovalListener<String, Long> removalListener;
-
-    @Before
-    public void setUp() throws Exception {
-        super.setUp();
-        this.removalListener = Mockito.mock(RemovalListener.class);
-    }
-
-    public void testLRUCache() {
-        executeRefCountedCacheTests(new LRUCache<>(SIZE, removalListener, value -> value));
-    }
-
-    public void testSegmentedCache() {
-        executeRefCountedCacheTests(
-            SegmentedCache.<String, Long>builder()
-                .capacity(SIZE)
-                .weigher(value -> value)
-                .listener(removalListener)
-                .concurrencyLevel(1)
-                .build()
-        );
-    }
-
-    void executeRefCountedCacheTests(RefCountedCache<String, Long> refCountedCache) {
-        // basic get and put operation
-        assertNull(refCountedCache.get("1"));
-        refCountedCache.put("1", 10L);
-        assertEquals(10L, (long) refCountedCache.get("1"));
-
-        // cache usage with ref ++ and --
-        assertEquals(10L, refCountedCache.usage().usage());
-        assertEquals(0L, refCountedCache.usage().activeUsage());
-        refCountedCache.incRef("1");
-        assertEquals(10L, refCountedCache.usage().usage());
-        assertEquals(10L, refCountedCache.usage().activeUsage());
-        refCountedCache.decRef("1");
-        assertEquals(10L, refCountedCache.usage().usage());
-        assertEquals(0L, refCountedCache.usage().activeUsage());
-
-        // put all delegation
-        Map<String, Long> toPutIntoCache = new HashMap<>() {
-            {
-                put("2", 20L);
-                put("3", 30L);
-            }
-        };
-        refCountedCache.putAll(toPutIntoCache);
-        toPutIntoCache.forEach((k, v) -> { assertEquals(v, refCountedCache.get(k)); });
-        assertEquals(60L, refCountedCache.usage().usage());
-        assertEquals(0L, refCountedCache.usage().activeUsage());
-
-        // since all entries has ref count = 0 first added one will be evicted first once usage >= capacity
-        refCountedCache.put("4", 40L);
-        refCountedCache.put("5", 10L);
-        assertNull(refCountedCache.get("1"));
-        assertNull(refCountedCache.get("2"));
-        Arrays.asList("3", "4", "5").forEach(k -> assertNotNull(refCountedCache.get(k)));
-        assertEquals(80L, refCountedCache.usage().usage());
-        assertEquals(0L, refCountedCache.usage().activeUsage());
-
-        // simple compute if present when present
-        refCountedCache.computeIfPresent("3", (k, v) -> { return v + 5; });
-        assertEquals(35L, (long) refCountedCache.get("3"));
-        assertEquals(85L, refCountedCache.usage().usage());
-        assertEquals(0L, refCountedCache.usage().activeUsage());
-
-        // simple compute if present when not present
-        refCountedCache.computeIfPresent("1", (k, v) -> {
-            fail("should not reach here");
-            return v + 5;
-        });
-        assertNull(refCountedCache.get("1"));
-
-        // inc ref all entries to prevent cache evictions
-        refCountedCache.incRef("3");
-        refCountedCache.incRef("4");
-        refCountedCache.incRef("5");
-        assertEquals(85L, refCountedCache.usage().usage());
-        assertEquals(85L, refCountedCache.usage().activeUsage());
-
-        // adding cache entry while > capacity won't put entry to cache
-        refCountedCache.put("6", 15L);
-        assertNull(refCountedCache.get("6"));
-        assertEquals(85L, refCountedCache.usage().usage());
-        assertEquals(85L, refCountedCache.usage().activeUsage());
-
-        // dec ref to add 6 instead of 3
-        refCountedCache.decRef("3");
-        refCountedCache.put("6", 15L);
-        assertNull(refCountedCache.get("3"));
-        assertEquals(15L, (long) refCountedCache.get("6"));
-        assertEquals(65L, refCountedCache.usage().usage());
-        assertEquals(50L, refCountedCache.usage().activeUsage());
-
-        // check stats
-        assertEquals(4, refCountedCache.stats().evictionCount());
-        assertEquals(9, refCountedCache.stats().hitCount());
-        assertEquals(7, refCountedCache.stats().missCount());
-        assertEquals(0, refCountedCache.stats().removeCount());
-        assertEquals(1, refCountedCache.stats().replaceCount());
-
-        // remove one entry
-        refCountedCache.remove("6");
-        assertNull(refCountedCache.get("6"));
-        assertEquals(50L, refCountedCache.usage().usage());
-        assertEquals(50L, refCountedCache.usage().activeUsage());
-        assertEquals(1, refCountedCache.stats().removeCount());
-    }
-}
diff --git a/server/src/test/java/org/opensearch/index/store/remote/utils/cache/SegmentedCacheTests.java b/server/src/test/java/org/opensearch/index/store/remote/utils/cache/SegmentedCacheTests.java
new file mode 100644
index 0000000000000..4081bf4d61907
--- /dev/null
+++ b/server/src/test/java/org/opensearch/index/store/remote/utils/cache/SegmentedCacheTests.java
@@ -0,0 +1,17 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.index.store.remote.utils.cache;
+
+public class SegmentedCacheTests extends RefCountedCacheTestCase {
+    public SegmentedCacheTests() {
+        super(
+            SegmentedCache.<String, Long>builder().capacity(CAPACITY).weigher(value -> value).listener(n -> {}).concurrencyLevel(1).build()
+        );
+    }
+}
diff --git a/server/src/test/java/org/opensearch/index/translog/listener/TranslogListenerTests.java b/server/src/test/java/org/opensearch/index/translog/listener/TranslogListenerTests.java
index 1f28e32a6dbec..3a27d26a630d6 100644
--- a/server/src/test/java/org/opensearch/index/translog/listener/TranslogListenerTests.java
+++ b/server/src/test/java/org/opensearch/index/translog/listener/TranslogListenerTests.java
@@ -98,7 +98,9 @@ public void onFailure(String reason, Exception ex) {
         TranslogEventListener throwingListener = (TranslogEventListener) Proxy.newProxyInstance(
             TranslogEventListener.class.getClassLoader(),
             new Class[] { TranslogEventListener.class },
-            (a, b, c) -> { throw new RuntimeException(); }
+            (a, b, c) -> {
+                throw new RuntimeException();
+            }
         );
 
         final List<TranslogEventListener> translogEventListeners = new LinkedList<>(Arrays.asList(listener, throwingListener, listener));
diff --git a/server/src/test/java/org/opensearch/indices/recovery/PeerRecoveryTargetServiceTests.java b/server/src/test/java/org/opensearch/indices/recovery/PeerRecoveryTargetServiceTests.java
index a50089831b3e9..ff4058f953642 100644
--- a/server/src/test/java/org/opensearch/indices/recovery/PeerRecoveryTargetServiceTests.java
+++ b/server/src/test/java/org/opensearch/indices/recovery/PeerRecoveryTargetServiceTests.java
@@ -148,7 +148,9 @@ public void testWriteFileChunksConcurrently() throws Exception {
                             r.content(),
                             r.lastChunk(),
                             r.totalTranslogOps(),
-                            ActionListener.wrap(ignored -> {}, e -> { throw new AssertionError(e); })
+                            ActionListener.wrap(ignored -> {}, e -> {
+                                throw new AssertionError(e);
+                            })
                         );
                     }
                 } catch (Exception e) {
diff --git a/server/src/test/java/org/opensearch/indices/replication/OngoingSegmentReplicationsTests.java b/server/src/test/java/org/opensearch/indices/replication/OngoingSegmentReplicationsTests.java
index bd3106454f49b..8cb7a5f6d8929 100644
--- a/server/src/test/java/org/opensearch/indices/replication/OngoingSegmentReplicationsTests.java
+++ b/server/src/test/java/org/opensearch/indices/replication/OngoingSegmentReplicationsTests.java
@@ -9,7 +9,6 @@
 package org.opensearch.indices.replication;
 
 import org.junit.Assert;
-import org.opensearch.OpenSearchException;
 import org.opensearch.action.ActionListener;
 import org.opensearch.cluster.metadata.IndexMetadata;
 import org.opensearch.cluster.node.DiscoveryNode;
@@ -33,8 +32,7 @@
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.TimeUnit;
+import java.util.Set;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
 
@@ -76,13 +74,7 @@ public void setUp() throws Exception {
         ShardId testShardId = primary.shardId();
 
         // This mirrors the creation of the ReplicationCheckpoint inside CopyState
-        testCheckpoint = new ReplicationCheckpoint(
-            testShardId,
-            primary.getOperationPrimaryTerm(),
-            0L,
-            primary.getProcessedLocalCheckpoint(),
-            0L
-        );
+        testCheckpoint = new ReplicationCheckpoint(testShardId, primary.getOperationPrimaryTerm(), 0L, 0L);
         IndexService mockIndexService = mock(IndexService.class);
         when(mockIndicesService.indexService(testShardId.getIndex())).thenReturn(mockIndexService);
         when(mockIndexService.getShard(testShardId.id())).thenReturn(primary);
@@ -284,7 +276,8 @@ public void testShardAlreadyReplicatingToNode() throws IOException {
             listener.onResponse(null);
         };
         replications.prepareForReplication(request, segmentSegmentFileChunkWriter);
-        assertThrows(OpenSearchException.class, () -> { replications.prepareForReplication(request, segmentSegmentFileChunkWriter); });
+        CopyState copyState = replications.prepareForReplication(request, segmentSegmentFileChunkWriter);
+        assertEquals(1, copyState.refCount());
     }
 
     public void testStartReplicationWithNoFilesToFetch() throws IOException {
@@ -365,4 +358,45 @@ public void testCancelAllReplicationsForShard() throws IOException {
         assertEquals(0, replications.cachedCopyStateSize());
         closeShards(replica_2);
     }
+
+    public void testCancelForMissingIds() throws IOException {
+        // This tests when primary has multiple ongoing replications.
+        IndexShard replica_2 = newShard(primary.shardId(), false);
+        recoverReplica(replica_2, primary, true);
+
+        OngoingSegmentReplications replications = new OngoingSegmentReplications(mockIndicesService, recoverySettings);
+        final String replicaAllocationId = replica.routingEntry().allocationId().getId();
+        final CheckpointInfoRequest request = new CheckpointInfoRequest(1L, replicaAllocationId, primaryDiscoveryNode, testCheckpoint);
+
+        final CopyState copyState = replications.prepareForReplication(request, mock(FileChunkWriter.class));
+        assertEquals(1, copyState.refCount());
+
+        final String replica_2AllocationId = replica_2.routingEntry().allocationId().getId();
+        final CheckpointInfoRequest secondRequest = new CheckpointInfoRequest(
+            1L,
+            replica_2AllocationId,
+            replicaDiscoveryNode,
+            testCheckpoint
+        );
+        replications.prepareForReplication(secondRequest, mock(FileChunkWriter.class));
+
+        assertEquals(2, copyState.refCount());
+        assertEquals(2, replications.size());
+        assertTrue(replications.getHandlers().containsKey(replicaAllocationId));
+        assertTrue(replications.getHandlers().containsKey(replica_2AllocationId));
+        assertEquals(1, replications.cachedCopyStateSize());
+
+        replications.clearOutOfSyncIds(primary.shardId(), Set.of(replica_2AllocationId));
+        assertEquals(1, copyState.refCount());
+        assertEquals(1, replications.size());
+        assertTrue(replications.getHandlers().containsKey(replica_2AllocationId));
+        assertEquals(1, replications.cachedCopyStateSize());
+
+        // cancel the primary's ongoing replications.
+        replications.clearOutOfSyncIds(primary.shardId(), Collections.emptySet());
+        assertEquals(0, copyState.refCount());
+        assertEquals(0, replications.size());
+        assertEquals(0, replications.cachedCopyStateSize());
+        closeShards(replica_2);
+    }
 }
diff --git a/server/src/test/java/org/opensearch/indices/replication/PrimaryShardReplicationSourceTests.java b/server/src/test/java/org/opensearch/indices/replication/PrimaryShardReplicationSourceTests.java
index 323445bee1274..d925956bd95ef 100644
--- a/server/src/test/java/org/opensearch/indices/replication/PrimaryShardReplicationSourceTests.java
+++ b/server/src/test/java/org/opensearch/indices/replication/PrimaryShardReplicationSourceTests.java
@@ -50,6 +50,8 @@ public class PrimaryShardReplicationSourceTests extends IndexShardTestCase {
     private IndexShard indexShard;
     private DiscoveryNode sourceNode;
 
+    private RecoverySettings recoverySettings;
+
     @Override
     public void setUp() throws Exception {
         super.setUp();
@@ -73,6 +75,7 @@ public void setUp() throws Exception {
 
         indexShard = newStartedShard(true);
 
+        this.recoverySettings = recoverySettings;
         replicationSource = new PrimaryShardReplicationSource(
             localNode,
             indexShard.routingEntry().allocationId().toString(),
@@ -90,13 +93,7 @@ public void tearDown() throws Exception {
     }
 
     public void testGetCheckpointMetadata() {
-        final ReplicationCheckpoint checkpoint = new ReplicationCheckpoint(
-            indexShard.shardId(),
-            PRIMARY_TERM,
-            SEGMENTS_GEN,
-            SEQ_NO,
-            VERSION
-        );
+        final ReplicationCheckpoint checkpoint = new ReplicationCheckpoint(indexShard.shardId(), PRIMARY_TERM, SEGMENTS_GEN, VERSION);
         replicationSource.getCheckpointMetadata(REPLICATION_ID, checkpoint, mock(ActionListener.class));
         CapturingTransport.CapturedRequest[] requestList = transport.getCapturedRequestsAndClear();
         assertEquals(1, requestList.length);
@@ -107,13 +104,7 @@ public void testGetCheckpointMetadata() {
     }
 
     public void testGetSegmentFiles() {
-        final ReplicationCheckpoint checkpoint = new ReplicationCheckpoint(
-            indexShard.shardId(),
-            PRIMARY_TERM,
-            SEGMENTS_GEN,
-            SEQ_NO,
-            VERSION
-        );
+        final ReplicationCheckpoint checkpoint = new ReplicationCheckpoint(indexShard.shardId(), PRIMARY_TERM, SEGMENTS_GEN, VERSION);
         StoreFileMetadata testMetadata = new StoreFileMetadata("testFile", 1L, "checksum", Version.LATEST);
         replicationSource.getSegmentFiles(
             REPLICATION_ID,
@@ -130,15 +121,31 @@ public void testGetSegmentFiles() {
         assertTrue(capturedRequest.request instanceof GetSegmentFilesRequest);
     }
 
+    /**
+     * This test verifies the transport request timeout value for fetching the segment files.
+     */
+    public void testTransportTimeoutForGetSegmentFilesAction() {
+        long fileSize = (long) (Math.pow(10, 9));
+        final ReplicationCheckpoint checkpoint = new ReplicationCheckpoint(indexShard.shardId(), PRIMARY_TERM, SEGMENTS_GEN, VERSION);
+        StoreFileMetadata testMetadata = new StoreFileMetadata("testFile", fileSize, "checksum", Version.LATEST);
+        replicationSource.getSegmentFiles(
+            REPLICATION_ID,
+            checkpoint,
+            Arrays.asList(testMetadata),
+            mock(Store.class),
+            mock(ActionListener.class)
+        );
+        CapturingTransport.CapturedRequest[] requestList = transport.getCapturedRequestsAndClear();
+        assertEquals(1, requestList.length);
+        CapturingTransport.CapturedRequest capturedRequest = requestList[0];
+        assertEquals(SegmentReplicationSourceService.Actions.GET_SEGMENT_FILES, capturedRequest.action);
+        assertEquals(sourceNode, capturedRequest.node);
+        assertEquals(recoverySettings.internalActionLongTimeout(), capturedRequest.options.timeout());
+    }
+
     public void testGetSegmentFiles_CancelWhileRequestOpen() throws InterruptedException {
         CountDownLatch latch = new CountDownLatch(1);
-        final ReplicationCheckpoint checkpoint = new ReplicationCheckpoint(
-            indexShard.shardId(),
-            PRIMARY_TERM,
-            SEGMENTS_GEN,
-            SEQ_NO,
-            VERSION
-        );
+        final ReplicationCheckpoint checkpoint = new ReplicationCheckpoint(indexShard.shardId(), PRIMARY_TERM, SEGMENTS_GEN, VERSION);
         StoreFileMetadata testMetadata = new StoreFileMetadata("testFile", 1L, "checksum", Version.LATEST);
         replicationSource.getSegmentFiles(
             REPLICATION_ID,
diff --git a/server/src/test/java/org/opensearch/indices/replication/SegmentFileTransferHandlerTests.java b/server/src/test/java/org/opensearch/indices/replication/SegmentFileTransferHandlerTests.java
index 63dab4f8883e8..26c55c30e2af3 100644
--- a/server/src/test/java/org/opensearch/indices/replication/SegmentFileTransferHandlerTests.java
+++ b/server/src/test/java/org/opensearch/indices/replication/SegmentFileTransferHandlerTests.java
@@ -245,16 +245,13 @@ public void testSendFiles_CorruptIndexException() throws Exception {
         );
 
         doNothing().when(shard).failShard(anyString(), any());
-        assertThrows(
-            CorruptIndexException.class,
-            () -> {
-                handler.handleErrorOnSendFiles(
-                    shard.store(),
-                    new CorruptIndexException("test", "test"),
-                    new StoreFileMetadata[] { SEGMENTS_FILE }
-                );
-            }
-        );
+        assertThrows(CorruptIndexException.class, () -> {
+            handler.handleErrorOnSendFiles(
+                shard.store(),
+                new CorruptIndexException("test", "test"),
+                new StoreFileMetadata[] { SEGMENTS_FILE }
+            );
+        });
 
         verify(shard, times(1)).failShard(any(), any());
     }
diff --git a/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationSourceHandlerTests.java b/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationSourceHandlerTests.java
index b5d8b2baf40dc..607f9dd91e35e 100644
--- a/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationSourceHandlerTests.java
+++ b/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationSourceHandlerTests.java
@@ -73,7 +73,7 @@ public void testSendFiles() throws IOException {
             chunkWriter,
             threadPool,
             copyState,
-            primary.routingEntry().allocationId().getId(),
+            replica.routingEntry().allocationId().getId(),
             5000,
             1
         );
@@ -111,7 +111,7 @@ public void testSendFiles_emptyRequest() throws IOException {
             chunkWriter,
             threadPool,
             copyState,
-            primary.routingEntry().allocationId().getId(),
+            replica.routingEntry().allocationId().getId(),
             5000,
             1
         );
@@ -191,7 +191,7 @@ public void testReplicationAlreadyRunning() throws IOException {
             chunkWriter,
             threadPool,
             copyState,
-            primary.routingEntry().allocationId().getId(),
+            replica.routingEntry().allocationId().getId(),
             5000,
             1
         );
diff --git a/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationSourceServiceTests.java b/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationSourceServiceTests.java
index 6183f1e5d9dfb..66df13b89b4c3 100644
--- a/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationSourceServiceTests.java
+++ b/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationSourceServiceTests.java
@@ -55,13 +55,7 @@ public void setUp() throws Exception {
         when(mockIndexService.getShard(testShardId.id())).thenReturn(mockIndexShard);
 
         // This mirrors the creation of the ReplicationCheckpoint inside CopyState
-        testCheckpoint = new ReplicationCheckpoint(
-            testShardId,
-            mockIndexShard.getOperationPrimaryTerm(),
-            0L,
-            mockIndexShard.getProcessedLocalCheckpoint(),
-            0L
-        );
+        testCheckpoint = new ReplicationCheckpoint(testShardId, mockIndexShard.getOperationPrimaryTerm(), 0L, 0L);
         testThreadPool = new TestThreadPool("test", Settings.EMPTY);
         CapturingTransport transport = new CapturingTransport();
         localNode = new DiscoveryNode("local", buildNewFakeTransportAddress(), Version.CURRENT);
diff --git a/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationTargetServiceTests.java b/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationTargetServiceTests.java
index 69e1e6f8de09b..bae0afb5bcc3b 100644
--- a/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationTargetServiceTests.java
+++ b/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationTargetServiceTests.java
@@ -65,7 +65,7 @@ public void setUp() throws Exception {
         primaryShard = newStartedShard(true, settings);
         replicaShard = newShard(false, settings, new NRTReplicationEngineFactory());
         recoverReplica(replicaShard, primaryShard, true, getReplicationFunc(replicaShard));
-        checkpoint = new ReplicationCheckpoint(replicaShard.shardId(), 0L, 0L, 0L, 0L);
+        checkpoint = new ReplicationCheckpoint(replicaShard.shardId(), 0L, 0L, 0L);
         SegmentReplicationSourceFactory replicationSourceFactory = mock(SegmentReplicationSourceFactory.class);
         replicationSource = mock(SegmentReplicationSource.class);
         when(replicationSourceFactory.get(replicaShard)).thenReturn(replicationSource);
@@ -76,14 +76,12 @@ public void setUp() throws Exception {
             initialCheckpoint.getShardId(),
             initialCheckpoint.getPrimaryTerm(),
             initialCheckpoint.getSegmentsGen(),
-            initialCheckpoint.getSeqNo(),
             initialCheckpoint.getSegmentInfosVersion() + 1
         );
         newPrimaryCheckpoint = new ReplicationCheckpoint(
             initialCheckpoint.getShardId(),
             initialCheckpoint.getPrimaryTerm() + 1,
             initialCheckpoint.getSegmentsGen(),
-            initialCheckpoint.getSeqNo(),
             initialCheckpoint.getSegmentInfosVersion() + 1
         );
     }
diff --git a/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationTargetTests.java b/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationTargetTests.java
index 7e3fca9008bfb..599e73b548ddb 100644
--- a/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationTargetTests.java
+++ b/server/src/test/java/org/opensearch/indices/replication/SegmentReplicationTargetTests.java
@@ -55,7 +55,6 @@
 import java.util.Arrays;
 
 import static org.mockito.ArgumentMatchers.any;
-import static org.mockito.ArgumentMatchers.anyLong;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.spy;
@@ -97,7 +96,7 @@ public void setUp() throws Exception {
         indexShard = newStartedShard(false, indexSettings, new NRTReplicationEngineFactory());
         spyIndexShard = spy(indexShard);
 
-        Mockito.doNothing().when(spyIndexShard).finalizeReplication(any(SegmentInfos.class), anyLong());
+        Mockito.doNothing().when(spyIndexShard).finalizeReplication(any(SegmentInfos.class));
         testSegmentInfos = spyIndexShard.store().readLastCommittedSegmentsInfo();
         buffer = new ByteBuffersDataOutput();
         try (ByteBuffersIndexOutput indexOutput = new ByteBuffersIndexOutput(buffer, "", null)) {
@@ -107,7 +106,6 @@ public void setUp() throws Exception {
             spyIndexShard.shardId(),
             spyIndexShard.getPendingPrimaryTerm(),
             testSegmentInfos.getGeneration(),
-            spyIndexShard.seqNoStats().getLocalCheckpoint(),
             testSegmentInfos.version
         );
     }
@@ -147,7 +145,7 @@ public void getSegmentFiles(
             @Override
             public void onResponse(Void replicationResponse) {
                 try {
-                    verify(spyIndexShard, times(1)).finalizeReplication(any(), anyLong());
+                    verify(spyIndexShard, times(1)).finalizeReplication(any());
                     segrepTarget.markAsDone();
                 } catch (IOException ex) {
                     Assert.fail();
@@ -277,7 +275,7 @@ public void getSegmentFiles(
         );
         segrepTarget = new SegmentReplicationTarget(repCheckpoint, spyIndexShard, segrepSource, segRepListener);
 
-        doThrow(exception).when(spyIndexShard).finalizeReplication(any(), anyLong());
+        doThrow(exception).when(spyIndexShard).finalizeReplication(any());
 
         segrepTarget.startReplication(new ActionListener<Void>() {
             @Override
@@ -322,7 +320,7 @@ public void getSegmentFiles(
         );
         segrepTarget = new SegmentReplicationTarget(repCheckpoint, spyIndexShard, segrepSource, segRepListener);
 
-        doThrow(exception).when(spyIndexShard).finalizeReplication(any(), anyLong());
+        doThrow(exception).when(spyIndexShard).finalizeReplication(any());
 
         segrepTarget.startReplication(new ActionListener<Void>() {
             @Override
@@ -374,8 +372,8 @@ public void onResponse(Void replicationResponse) {
 
             @Override
             public void onFailure(Exception e) {
-                assert (e instanceof IllegalStateException);
-                segrepTarget.fail(new ReplicationFailedException(e), false);
+                assert (e instanceof ReplicationFailedException);
+                assert (e.getMessage().contains("different segment files"));
             }
         });
     }
diff --git a/server/src/test/java/org/opensearch/indices/replication/checkpoint/PublishCheckpointActionTests.java b/server/src/test/java/org/opensearch/indices/replication/checkpoint/PublishCheckpointActionTests.java
index 704b40b05c49d..2c05fbc9328e5 100644
--- a/server/src/test/java/org/opensearch/indices/replication/checkpoint/PublishCheckpointActionTests.java
+++ b/server/src/test/java/org/opensearch/indices/replication/checkpoint/PublishCheckpointActionTests.java
@@ -8,9 +8,9 @@
 
 package org.opensearch.indices.replication.checkpoint;
 
-import org.opensearch.OpenSearchException;
 import org.opensearch.action.ActionListener;
 import org.opensearch.action.support.ActionFilters;
+import org.opensearch.action.support.ActionTestUtils;
 import org.opensearch.action.support.PlainActionFuture;
 import org.opensearch.action.support.replication.ReplicationMode;
 import org.opensearch.action.support.replication.TransportReplicationAction;
@@ -33,6 +33,7 @@
 import java.util.Collections;
 import java.util.concurrent.atomic.AtomicBoolean;
 
+import static org.hamcrest.Matchers.sameInstance;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 import static org.mockito.Mockito.verify;
@@ -103,10 +104,13 @@ public void testPublishCheckpointActionOnPrimary() {
             mockTargetService
         );
 
-        final ReplicationCheckpoint checkpoint = new ReplicationCheckpoint(indexShard.shardId(), 1111, 111, 11, 1);
+        final ReplicationCheckpoint checkpoint = new ReplicationCheckpoint(indexShard.shardId(), 1111, 11, 1);
         final PublishCheckpointRequest request = new PublishCheckpointRequest(checkpoint);
 
-        expectThrows(OpenSearchException.class, () -> { action.shardOperationOnPrimary(request, indexShard, mock(ActionListener.class)); });
+        action.shardOperationOnPrimary(request, indexShard, ActionTestUtils.assertNoFailureListener(result -> {
+            // we should forward the request containing the current publish checkpoint to the replica
+            assertThat(result.replicaRequest(), sameInstance(request));
+        }));
     }
 
     public void testPublishCheckpointActionOnReplica() {
@@ -135,7 +139,7 @@ public void testPublishCheckpointActionOnReplica() {
             mockTargetService
         );
 
-        final ReplicationCheckpoint checkpoint = new ReplicationCheckpoint(indexShard.shardId(), 1111, 111, 11, 1);
+        final ReplicationCheckpoint checkpoint = new ReplicationCheckpoint(indexShard.shardId(), 1111, 11, 1);
 
         final PublishCheckpointRequest request = new PublishCheckpointRequest(checkpoint);
 
diff --git a/server/src/test/java/org/opensearch/indices/replication/common/CopyStateTests.java b/server/src/test/java/org/opensearch/indices/replication/common/CopyStateTests.java
index 6f2be9db6b2dd..a87a8de206a39 100644
--- a/server/src/test/java/org/opensearch/indices/replication/common/CopyStateTests.java
+++ b/server/src/test/java/org/opensearch/indices/replication/common/CopyStateTests.java
@@ -12,7 +12,6 @@
 import org.apache.lucene.index.IndexFileNames;
 import org.apache.lucene.index.SegmentInfos;
 import org.apache.lucene.util.Version;
-import org.opensearch.common.collect.Map;
 import org.opensearch.common.collect.Tuple;
 import org.opensearch.common.concurrent.GatedCloseable;
 import org.opensearch.index.shard.IndexShard;
@@ -23,6 +22,7 @@
 import org.opensearch.indices.replication.checkpoint.ReplicationCheckpoint;
 
 import java.io.IOException;
+import java.util.Map;
 
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
@@ -67,13 +67,7 @@ public static IndexShard createMockIndexShard() throws IOException {
         when(mockShard.store()).thenReturn(mockStore);
 
         SegmentInfos testSegmentInfos = new SegmentInfos(Version.LATEST.major);
-        ReplicationCheckpoint testCheckpoint = new ReplicationCheckpoint(
-            mockShard.shardId(),
-            mockShard.getOperationPrimaryTerm(),
-            0L,
-            mockShard.getProcessedLocalCheckpoint(),
-            0L
-        );
+        ReplicationCheckpoint testCheckpoint = new ReplicationCheckpoint(mockShard.shardId(), mockShard.getOperationPrimaryTerm(), 0L, 0L);
         final Tuple<GatedCloseable<SegmentInfos>, ReplicationCheckpoint> gatedCloseableReplicationCheckpointTuple = new Tuple<>(
             new GatedCloseable<>(testSegmentInfos, () -> {}),
             testCheckpoint
diff --git a/server/src/test/java/org/opensearch/ingest/CompoundProcessorTests.java b/server/src/test/java/org/opensearch/ingest/CompoundProcessorTests.java
index fb0c55fce28f1..b299ac4d66996 100644
--- a/server/src/test/java/org/opensearch/ingest/CompoundProcessorTests.java
+++ b/server/src/test/java/org/opensearch/ingest/CompoundProcessorTests.java
@@ -75,9 +75,9 @@ public void testEmpty() throws Exception {
     public void testSingleProcessor() throws Exception {
         LongSupplier relativeTimeProvider = mock(LongSupplier.class);
         when(relativeTimeProvider.getAsLong()).thenReturn(0L, TimeUnit.MILLISECONDS.toNanos(1));
-        TestProcessor processor = new TestProcessor(
-            ingestDocument -> { assertStats(0, ingestDocument.getFieldValue("compoundProcessor", CompoundProcessor.class), 1, 0, 0, 0); }
-        );
+        TestProcessor processor = new TestProcessor(ingestDocument -> {
+            assertStats(0, ingestDocument.getFieldValue("compoundProcessor", CompoundProcessor.class), 1, 0, 0, 0);
+        });
         CompoundProcessor compoundProcessor = new CompoundProcessor(relativeTimeProvider, processor);
         ingestDocument.setFieldValue("compoundProcessor", compoundProcessor); // ugly hack to assert current count = 1
         assertThat(compoundProcessor.getProcessors().size(), equalTo(1));
diff --git a/server/src/test/java/org/opensearch/ingest/ConditionalProcessorTests.java b/server/src/test/java/org/opensearch/ingest/ConditionalProcessorTests.java
index 1550dd65442a4..a383ab9b97918 100644
--- a/server/src/test/java/org/opensearch/ingest/ConditionalProcessorTests.java
+++ b/server/src/test/java/org/opensearch/ingest/ConditionalProcessorTests.java
@@ -164,21 +164,10 @@ public void testActsOnImmutableData() throws Exception {
     }
 
     public void testPrecompiledError() {
-        ScriptService scriptService = MockScriptService.singleContext(
-            IngestConditionalScript.CONTEXT,
-            code -> {
-                throw new ScriptException(
-                    "bad script",
-                    new ParseException("error", 0),
-                    org.opensearch.common.collect.List.of(),
-                    "",
-                    "lang",
-                    null
-                );
-            },
-            org.opensearch.common.collect.Map.of()
-        );
-        Script script = new Script(ScriptType.INLINE, "lang", "foo", org.opensearch.common.collect.Map.of());
+        ScriptService scriptService = MockScriptService.singleContext(IngestConditionalScript.CONTEXT, code -> {
+            throw new ScriptException("bad script", new ParseException("error", 0), List.of(), "", "lang", null);
+        }, Map.of());
+        Script script = new Script(ScriptType.INLINE, "lang", "foo", Map.of());
         ScriptException e = expectThrows(ScriptException.class, () -> new ConditionalProcessor(null, null, script, scriptService, null));
         assertThat(e.getMessage(), equalTo("bad script"));
     }
@@ -186,17 +175,10 @@ public void testPrecompiledError() {
     public void testRuntimeCompileError() {
         AtomicBoolean fail = new AtomicBoolean(false);
         Map<String, StoredScriptSource> storedScripts = new HashMap<>();
-        storedScripts.put("foo", new StoredScriptSource("lang", "", org.opensearch.common.collect.Map.of()));
+        storedScripts.put("foo", new StoredScriptSource("lang", "", Map.of()));
         ScriptService scriptService = MockScriptService.singleContext(IngestConditionalScript.CONTEXT, code -> {
             if (fail.get()) {
-                throw new ScriptException(
-                    "bad script",
-                    new ParseException("error", 0),
-                    org.opensearch.common.collect.List.of(),
-                    "",
-                    "lang",
-                    null
-                );
+                throw new ScriptException("bad script", new ParseException("error", 0), List.of(), "", "lang", null);
             } else {
                 return params -> new IngestConditionalScript(params) {
                     @Override
@@ -206,12 +188,12 @@ public boolean execute(Map<String, Object> ctx) {
                 };
             }
         }, storedScripts);
-        Script script = new Script(ScriptType.STORED, null, "foo", org.opensearch.common.collect.Map.of());
+        Script script = new Script(ScriptType.STORED, null, "foo", Map.of());
         ConditionalProcessor processor = new ConditionalProcessor(null, null, script, scriptService, null);
         fail.set(true);
         // must change the script source or the cached version will be used
-        storedScripts.put("foo", new StoredScriptSource("lang", "changed", org.opensearch.common.collect.Map.of()));
-        IngestDocument ingestDoc = new IngestDocument(org.opensearch.common.collect.Map.of(), org.opensearch.common.collect.Map.of());
+        storedScripts.put("foo", new StoredScriptSource("lang", "changed", Map.of()));
+        IngestDocument ingestDoc = new IngestDocument(Map.of(), Map.of());
         processor.execute(ingestDoc, (doc, e) -> { assertThat(e.getMessage(), equalTo("bad script")); });
     }
 
@@ -224,11 +206,11 @@ public boolean execute(Map<String, Object> ctx) {
                     throw new IllegalArgumentException("runtime problem");
                 }
             },
-            org.opensearch.common.collect.Map.of()
+            Map.of()
         );
-        Script script = new Script(ScriptType.INLINE, "lang", "foo", org.opensearch.common.collect.Map.of());
+        Script script = new Script(ScriptType.INLINE, "lang", "foo", Map.of());
         ConditionalProcessor processor = new ConditionalProcessor(null, null, script, scriptService, null);
-        IngestDocument ingestDoc = new IngestDocument(org.opensearch.common.collect.Map.of(), org.opensearch.common.collect.Map.of());
+        IngestDocument ingestDoc = new IngestDocument(Map.of(), Map.of());
         processor.execute(ingestDoc, (doc, e) -> { assertThat(e.getMessage(), equalTo("runtime problem")); });
     }
 
diff --git a/server/src/test/java/org/opensearch/ingest/IngestDocumentTests.java b/server/src/test/java/org/opensearch/ingest/IngestDocumentTests.java
index a6ea02a5423c4..8358dadf9cc3a 100644
--- a/server/src/test/java/org/opensearch/ingest/IngestDocumentTests.java
+++ b/server/src/test/java/org/opensearch/ingest/IngestDocumentTests.java
@@ -471,7 +471,7 @@ public void testListAppendFieldValueWithDuplicate() {
         @SuppressWarnings("unchecked")
         List<Object> list = (List<Object>) object;
         assertThat(list.size(), equalTo(3));
-        assertThat(list, equalTo(org.opensearch.common.collect.List.of("foo", "bar", "baz")));
+        assertThat(list, equalTo(List.of("foo", "bar", "baz")));
     }
 
     public void testListAppendFieldValueWithoutDuplicate() {
@@ -481,7 +481,7 @@ public void testListAppendFieldValueWithoutDuplicate() {
         @SuppressWarnings("unchecked")
         List<Object> list = (List<Object>) object;
         assertThat(list.size(), equalTo(4));
-        assertThat(list, equalTo(org.opensearch.common.collect.List.of("foo", "bar", "baz", "foo2")));
+        assertThat(list, equalTo(List.of("foo", "bar", "baz", "foo2")));
     }
 
     public void testListAppendFieldValues() {
@@ -499,7 +499,7 @@ public void testListAppendFieldValues() {
     }
 
     public void testListAppendFieldValuesWithoutDuplicates() {
-        ingestDocument.appendFieldValue("list2", org.opensearch.common.collect.List.of("foo", "bar", "baz", "foo2"), false);
+        ingestDocument.appendFieldValue("list2", List.of("foo", "bar", "baz", "foo2"), false);
         Object object = ingestDocument.getSourceAndMetadata().get("list2");
         assertThat(object, instanceOf(List.class));
         @SuppressWarnings("unchecked")
diff --git a/server/src/test/java/org/opensearch/ingest/PipelineProcessorTests.java b/server/src/test/java/org/opensearch/ingest/PipelineProcessorTests.java
index 86e4dd261d408..9f8dda15eeb65 100644
--- a/server/src/test/java/org/opensearch/ingest/PipelineProcessorTests.java
+++ b/server/src/test/java/org/opensearch/ingest/PipelineProcessorTests.java
@@ -172,25 +172,16 @@ public void testPipelineProcessorWithPipelineChain() throws Exception {
             pipeline2Id,
             null,
             null,
-            new CompoundProcessor(
-                true,
-                Arrays.asList(
-                    new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key1, randomInt()); }),
-                    pipeline2Processor
-                ),
-                Collections.emptyList()
-            ),
+            new CompoundProcessor(true, Arrays.asList(new TestProcessor(ingestDocument -> {
+                ingestDocument.setFieldValue(key1, randomInt());
+            }), pipeline2Processor), Collections.emptyList()),
             relativeTimeProvider
         );
         relativeTimeProvider = mock(LongSupplier.class);
         when(relativeTimeProvider.getAsLong()).thenReturn(0L, TimeUnit.MILLISECONDS.toNanos(2));
-        Pipeline pipeline3 = new Pipeline(
-            pipeline3Id,
-            null,
-            null,
-            new CompoundProcessor(new TestProcessor(ingestDocument -> { throw new RuntimeException("error"); })),
-            relativeTimeProvider
-        );
+        Pipeline pipeline3 = new Pipeline(pipeline3Id, null, null, new CompoundProcessor(new TestProcessor(ingestDocument -> {
+            throw new RuntimeException("error");
+        })), relativeTimeProvider);
         when(ingestService.getPipeline(pipeline1Id)).thenReturn(pipeline1);
         when(ingestService.getPipeline(pipeline2Id)).thenReturn(pipeline2);
         when(ingestService.getPipeline(pipeline3Id)).thenReturn(pipeline3);
diff --git a/server/src/test/java/org/opensearch/ingest/TrackingResultProcessorTests.java b/server/src/test/java/org/opensearch/ingest/TrackingResultProcessorTests.java
index 343b82e7c034b..16e60cec8c941 100644
--- a/server/src/test/java/org/opensearch/ingest/TrackingResultProcessorTests.java
+++ b/server/src/test/java/org/opensearch/ingest/TrackingResultProcessorTests.java
@@ -280,14 +280,17 @@ public void testActualCompoundProcessorWithFalseConditional() throws Exception {
             new HashMap<>(ScriptModule.CORE_CONTEXTS)
         );
 
-        CompoundProcessor compoundProcessor = new CompoundProcessor(
-            new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key1, randomInt()); }),
+        CompoundProcessor compoundProcessor = new CompoundProcessor(new TestProcessor(ingestDocument -> {
+            ingestDocument.setFieldValue(key1, randomInt());
+        }),
             new ConditionalProcessor(
                 randomAlphaOfLength(10),
                 null,
                 new Script(ScriptType.INLINE, Script.DEFAULT_SCRIPT_LANG, scriptName, Collections.emptyMap()),
                 scriptService,
-                new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key2, randomInt()); })
+                new TestProcessor(ingestDocument -> {
+                    ingestDocument.setFieldValue(key2, randomInt());
+                })
             ),
             new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key3, randomInt()); })
         );
@@ -331,16 +334,11 @@ public void testActualPipelineProcessor() throws Exception {
         String key2 = randomAlphaOfLength(10);
         String key3 = randomAlphaOfLength(10);
 
-        Pipeline pipeline = new Pipeline(
-            pipelineId,
-            null,
-            null,
-            new CompoundProcessor(
-                new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key1, randomInt()); }),
-                new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key2, randomInt()); }),
-                new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key3, randomInt()); })
-            )
-        );
+        Pipeline pipeline = new Pipeline(pipelineId, null, null, new CompoundProcessor(new TestProcessor(ingestDocument -> {
+            ingestDocument.setFieldValue(key1, randomInt());
+        }), new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key2, randomInt()); }), new TestProcessor(ingestDocument -> {
+            ingestDocument.setFieldValue(key3, randomInt());
+        })));
         when(ingestService.getPipeline(pipelineId)).thenReturn(pipeline);
 
         PipelineProcessor pipelineProcessor = factory.create(Collections.emptyMap(), null, null, pipelineConfig);
@@ -406,29 +404,24 @@ public void testActualPipelineProcessorWithTrueConditional() throws Exception {
             new HashMap<>(ScriptModule.CORE_CONTEXTS)
         );
 
-        Pipeline pipeline1 = new Pipeline(
-            pipelineId1,
-            null,
-            null,
-            new CompoundProcessor(
-                new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key1, randomInt()); }),
-                new ConditionalProcessor(
-                    randomAlphaOfLength(10),
-                    null,
-                    new Script(ScriptType.INLINE, Script.DEFAULT_SCRIPT_LANG, scriptName, Collections.emptyMap()),
-                    scriptService,
-                    factory.create(Collections.emptyMap(), "pipeline1", null, pipelineConfig2)
-                ),
-                new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key3, randomInt()); })
-            )
-        );
+        Pipeline pipeline1 = new Pipeline(pipelineId1, null, null, new CompoundProcessor(new TestProcessor(ingestDocument -> {
+            ingestDocument.setFieldValue(key1, randomInt());
+        }),
+            new ConditionalProcessor(
+                randomAlphaOfLength(10),
+                null,
+                new Script(ScriptType.INLINE, Script.DEFAULT_SCRIPT_LANG, scriptName, Collections.emptyMap()),
+                scriptService,
+                factory.create(Collections.emptyMap(), "pipeline1", null, pipelineConfig2)
+            ),
+            new TestProcessor(ingestDocument -> {
+                ingestDocument.setFieldValue(key3, randomInt());
+            })
+        ));
 
-        Pipeline pipeline2 = new Pipeline(
-            pipelineId2,
-            null,
-            null,
-            new CompoundProcessor(new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key2, randomInt()); }))
-        );
+        Pipeline pipeline2 = new Pipeline(pipelineId2, null, null, new CompoundProcessor(new TestProcessor(ingestDocument -> {
+            ingestDocument.setFieldValue(key2, randomInt());
+        })));
 
         when(ingestService.getPipeline(pipelineId1)).thenReturn(pipeline1);
         when(ingestService.getPipeline(pipelineId2)).thenReturn(pipeline2);
@@ -503,29 +496,24 @@ public void testActualPipelineProcessorWithFalseConditional() throws Exception {
             new HashMap<>(ScriptModule.CORE_CONTEXTS)
         );
 
-        Pipeline pipeline1 = new Pipeline(
-            pipelineId1,
-            null,
-            null,
-            new CompoundProcessor(
-                new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key1, randomInt()); }),
-                new ConditionalProcessor(
-                    randomAlphaOfLength(10),
-                    null,
-                    new Script(ScriptType.INLINE, Script.DEFAULT_SCRIPT_LANG, scriptName, Collections.emptyMap()),
-                    scriptService,
-                    factory.create(Collections.emptyMap(), null, null, pipelineConfig2)
-                ),
-                new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key3, randomInt()); })
-            )
-        );
+        Pipeline pipeline1 = new Pipeline(pipelineId1, null, null, new CompoundProcessor(new TestProcessor(ingestDocument -> {
+            ingestDocument.setFieldValue(key1, randomInt());
+        }),
+            new ConditionalProcessor(
+                randomAlphaOfLength(10),
+                null,
+                new Script(ScriptType.INLINE, Script.DEFAULT_SCRIPT_LANG, scriptName, Collections.emptyMap()),
+                scriptService,
+                factory.create(Collections.emptyMap(), null, null, pipelineConfig2)
+            ),
+            new TestProcessor(ingestDocument -> {
+                ingestDocument.setFieldValue(key3, randomInt());
+            })
+        ));
 
-        Pipeline pipeline2 = new Pipeline(
-            pipelineId2,
-            null,
-            null,
-            new CompoundProcessor(new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key2, randomInt()); }))
-        );
+        Pipeline pipeline2 = new Pipeline(pipelineId2, null, null, new CompoundProcessor(new TestProcessor(ingestDocument -> {
+            ingestDocument.setFieldValue(key2, randomInt());
+        })));
 
         when(ingestService.getPipeline(pipelineId1)).thenReturn(pipeline1);
         when(ingestService.getPipeline(pipelineId2)).thenReturn(pipeline2);
@@ -579,20 +567,18 @@ public void testActualPipelineProcessorWithHandledFailure() throws Exception {
         String key2 = randomAlphaOfLength(10);
         String key3 = randomAlphaOfLength(10);
 
-        Pipeline pipeline = new Pipeline(
-            pipelineId,
-            null,
-            null,
+        Pipeline pipeline = new Pipeline(pipelineId, null, null, new CompoundProcessor(new TestProcessor(ingestDocument -> {
+            ingestDocument.setFieldValue(key1, randomInt());
+        }),
             new CompoundProcessor(
-                new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key1, randomInt()); }),
-                new CompoundProcessor(
-                    false,
-                    Collections.singletonList(new TestProcessor(ingestDocument -> { throw exception; })),
-                    Collections.singletonList(new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key2, randomInt()); }))
-                ),
-                new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key3, randomInt()); })
-            )
-        );
+                false,
+                Collections.singletonList(new TestProcessor(ingestDocument -> { throw exception; })),
+                Collections.singletonList(new TestProcessor(ingestDocument -> {
+                    ingestDocument.setFieldValue(key2, randomInt());
+                }))
+            ),
+            new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key3, randomInt()); })
+        ));
         when(ingestService.getPipeline(pipelineId)).thenReturn(pipeline);
 
         PipelineProcessor pipelineProcessor = factory.create(Collections.emptyMap(), null, null, pipelineConfig);
@@ -650,7 +636,9 @@ public void testActualPipelineProcessorWithUnhandledFailure() throws Exception {
             null,
             new CompoundProcessor(
                 new TestProcessor(ingestDocument -> ingestDocument.setFieldValue(key1, randomInt())),
-                new TestProcessor(ingestDocument -> { throw exception; })
+                new TestProcessor(ingestDocument -> {
+                    throw exception;
+                })
             )
         );
         when(ingestService.getPipeline(pipelineId)).thenReturn(pipeline);
@@ -730,12 +718,9 @@ public void testActualPipelineProcessorRepeatedInvocation() throws Exception {
 
         String key1 = randomAlphaOfLength(10);
         PipelineProcessor pipelineProcessor = factory.create(Collections.emptyMap(), null, null, pipelineConfig);
-        Pipeline pipeline = new Pipeline(
-            pipelineId,
-            null,
-            null,
-            new CompoundProcessor(new TestProcessor(ingestDocument -> { ingestDocument.setFieldValue(key1, randomInt()); }))
-        );
+        Pipeline pipeline = new Pipeline(pipelineId, null, null, new CompoundProcessor(new TestProcessor(ingestDocument -> {
+            ingestDocument.setFieldValue(key1, randomInt());
+        })));
         when(ingestService.getPipeline(pipelineId)).thenReturn(pipeline);
 
         // calls the same pipeline twice
diff --git a/server/src/test/java/org/opensearch/lucene/misc/search/similarity/LegacyBM25SimilarityTests.java b/server/src/test/java/org/opensearch/lucene/misc/search/similarity/LegacyBM25SimilarityTests.java
index 209b0d959c8b0..c58847bb56a3b 100644
--- a/server/src/test/java/org/opensearch/lucene/misc/search/similarity/LegacyBM25SimilarityTests.java
+++ b/server/src/test/java/org/opensearch/lucene/misc/search/similarity/LegacyBM25SimilarityTests.java
@@ -36,10 +36,9 @@
 public class LegacyBM25SimilarityTests extends BaseSimilarityTestCase {
 
     public void testIllegalK1() {
-        IllegalArgumentException expected = expectThrows(
-            IllegalArgumentException.class,
-            () -> { new LegacyBM25Similarity(Float.POSITIVE_INFINITY, 0.75f); }
-        );
+        IllegalArgumentException expected = expectThrows(IllegalArgumentException.class, () -> {
+            new LegacyBM25Similarity(Float.POSITIVE_INFINITY, 0.75f);
+        });
         assertTrue(expected.getMessage().contains("illegal k1 value"));
 
         expected = expectThrows(IllegalArgumentException.class, () -> { new LegacyBM25Similarity(-1, 0.75f); });
diff --git a/server/src/test/java/org/opensearch/plugins/PluginsServiceTests.java b/server/src/test/java/org/opensearch/plugins/PluginsServiceTests.java
index c7586777387b8..1787d21af38ea 100644
--- a/server/src/test/java/org/opensearch/plugins/PluginsServiceTests.java
+++ b/server/src/test/java/org/opensearch/plugins/PluginsServiceTests.java
@@ -922,10 +922,9 @@ public void testNoExtensionConstructors() {
         class TestExtension implements TestExtensionPoint {
             private TestExtension() {}
         }
-        IllegalStateException e = expectThrows(
-            IllegalStateException.class,
-            () -> { PluginsService.createExtension(TestExtension.class, TestExtensionPoint.class, plugin); }
-        );
+        IllegalStateException e = expectThrows(IllegalStateException.class, () -> {
+            PluginsService.createExtension(TestExtension.class, TestExtensionPoint.class, plugin);
+        });
 
         assertThat(
             e,
@@ -950,10 +949,9 @@ public TestExtension(TestPlugin plugin) {
 
             }
         }
-        IllegalStateException e = expectThrows(
-            IllegalStateException.class,
-            () -> { PluginsService.createExtension(TestExtension.class, TestExtensionPoint.class, plugin); }
-        );
+        IllegalStateException e = expectThrows(IllegalStateException.class, () -> {
+            PluginsService.createExtension(TestExtension.class, TestExtensionPoint.class, plugin);
+        });
 
         assertThat(
             e,
@@ -971,10 +969,9 @@ public TestExtension(TestPlugin plugin) {
 
     public void testBadSingleParameterConstructor() {
         TestPlugin plugin = new TestPlugin();
-        IllegalStateException e = expectThrows(
-            IllegalStateException.class,
-            () -> { PluginsService.createExtension(BadSingleParameterConstructorExtension.class, TestExtensionPoint.class, plugin); }
-        );
+        IllegalStateException e = expectThrows(IllegalStateException.class, () -> {
+            PluginsService.createExtension(BadSingleParameterConstructorExtension.class, TestExtensionPoint.class, plugin);
+        });
 
         assertThat(
             e,
@@ -996,10 +993,9 @@ public void testBadSingleParameterConstructor() {
 
     public void testTooManyParametersExtensionConstructors() {
         TestPlugin plugin = new TestPlugin();
-        IllegalStateException e = expectThrows(
-            IllegalStateException.class,
-            () -> { PluginsService.createExtension(TooManyParametersConstructorExtension.class, TestExtensionPoint.class, plugin); }
-        );
+        IllegalStateException e = expectThrows(IllegalStateException.class, () -> {
+            PluginsService.createExtension(TooManyParametersConstructorExtension.class, TestExtensionPoint.class, plugin);
+        });
 
         assertThat(
             e,
@@ -1019,10 +1015,9 @@ public void testTooManyParametersExtensionConstructors() {
 
     public void testThrowingConstructor() {
         TestPlugin plugin = new TestPlugin();
-        IllegalStateException e = expectThrows(
-            IllegalStateException.class,
-            () -> { PluginsService.createExtension(ThrowingConstructorExtension.class, TestExtensionPoint.class, plugin); }
-        );
+        IllegalStateException e = expectThrows(IllegalStateException.class, () -> {
+            PluginsService.createExtension(ThrowingConstructorExtension.class, TestExtensionPoint.class, plugin);
+        });
 
         assertThat(
             e,
diff --git a/server/src/test/java/org/opensearch/repositories/RepositoriesServiceTests.java b/server/src/test/java/org/opensearch/repositories/RepositoriesServiceTests.java
index 6a8999a205be2..2ceab293f1320 100644
--- a/server/src/test/java/org/opensearch/repositories/RepositoriesServiceTests.java
+++ b/server/src/test/java/org/opensearch/repositories/RepositoriesServiceTests.java
@@ -101,7 +101,7 @@ public void setUp() throws Exception {
         when(clusterApplierService.threadPool()).thenReturn(threadPool);
         final ClusterService clusterService = mock(ClusterService.class);
         when(clusterService.getClusterApplierService()).thenReturn(clusterApplierService);
-        Map<String, Repository.Factory> typesRegistry = org.opensearch.common.collect.Map.of(
+        Map<String, Repository.Factory> typesRegistry = Map.of(
             TestRepository.TYPE,
             TestRepository::new,
             MeteredRepositoryTypeA.TYPE,
@@ -391,7 +391,7 @@ public void close() {
 
     private static class MeteredRepositoryTypeA extends MeteredBlobStoreRepository {
         private static final String TYPE = "type-a";
-        private static final RepositoryStats STATS = new RepositoryStats(org.opensearch.common.collect.Map.of("GET", 10L));
+        private static final RepositoryStats STATS = new RepositoryStats(Map.of("GET", 10L));
 
         private MeteredRepositoryTypeA(RepositoryMetadata metadata, ClusterService clusterService) {
             super(
@@ -400,7 +400,7 @@ private MeteredRepositoryTypeA(RepositoryMetadata metadata, ClusterService clust
                 mock(NamedXContentRegistry.class),
                 clusterService,
                 mock(RecoverySettings.class),
-                org.opensearch.common.collect.Map.of("bucket", "bucket-a")
+                Map.of("bucket", "bucket-a")
             );
         }
 
@@ -422,7 +422,7 @@ public BlobPath basePath() {
 
     private static class MeteredRepositoryTypeB extends MeteredBlobStoreRepository {
         private static final String TYPE = "type-b";
-        private static final RepositoryStats STATS = new RepositoryStats(org.opensearch.common.collect.Map.of("LIST", 20L));
+        private static final RepositoryStats STATS = new RepositoryStats(Map.of("LIST", 20L));
 
         private MeteredRepositoryTypeB(RepositoryMetadata metadata, ClusterService clusterService) {
             super(
@@ -431,7 +431,7 @@ private MeteredRepositoryTypeB(RepositoryMetadata metadata, ClusterService clust
                 mock(NamedXContentRegistry.class),
                 clusterService,
                 mock(RecoverySettings.class),
-                org.opensearch.common.collect.Map.of("bucket", "bucket-b")
+                Map.of("bucket", "bucket-b")
             );
         }
 
diff --git a/server/src/test/java/org/opensearch/repositories/RepositoriesStatsArchiveTests.java b/server/src/test/java/org/opensearch/repositories/RepositoriesStatsArchiveTests.java
index 4ad3e1ef85f70..cf0b06a3f7d16 100644
--- a/server/src/test/java/org/opensearch/repositories/RepositoriesStatsArchiveTests.java
+++ b/server/src/test/java/org/opensearch/repositories/RepositoriesStatsArchiveTests.java
@@ -37,6 +37,7 @@
 import org.opensearch.test.OpenSearchTestCase;
 
 import java.util.List;
+import java.util.Map;
 import java.util.concurrent.atomic.AtomicLong;
 
 import static org.hamcrest.Matchers.equalTo;
@@ -60,19 +61,14 @@ public void testStatsAreEvictedOnceTheyAreOlderThanRetentionPeriod() {
         fakeRelativeClock.set(retentionTimeInMillis * 2);
         int statsToBeRetainedCount = randomInt(10);
         for (int i = 0; i < statsToBeRetainedCount; i++) {
-            RepositoryStatsSnapshot repoStats = createRepositoryStats(
-                new RepositoryStats(org.opensearch.common.collect.Map.of("GET", 10L))
-            );
+            RepositoryStatsSnapshot repoStats = createRepositoryStats(new RepositoryStats(Map.of("GET", 10L)));
             repositoriesStatsArchive.archive(repoStats);
         }
 
         List<RepositoryStatsSnapshot> archivedStats = repositoriesStatsArchive.getArchivedStats();
         assertThat(archivedStats.size(), equalTo(statsToBeRetainedCount));
         for (RepositoryStatsSnapshot repositoryStatsSnapshot : archivedStats) {
-            assertThat(
-                repositoryStatsSnapshot.getRepositoryStats().requestCounts,
-                equalTo(org.opensearch.common.collect.Map.of("GET", 10L))
-            );
+            assertThat(repositoryStatsSnapshot.getRepositoryStats().requestCounts, equalTo(Map.of("GET", 10L)));
         }
     }
 
@@ -129,7 +125,7 @@ private RepositoryStatsSnapshot createRepositoryStats(RepositoryStats repository
             UUIDs.randomBase64UUID(),
             randomAlphaOfLength(10),
             randomAlphaOfLength(10),
-            org.opensearch.common.collect.Map.of("bucket", randomAlphaOfLength(10)),
+            Map.of("bucket", randomAlphaOfLength(10)),
             System.currentTimeMillis(),
             null
         );
diff --git a/server/src/test/java/org/opensearch/repositories/fs/FsRepositoryTests.java b/server/src/test/java/org/opensearch/repositories/fs/FsRepositoryTests.java
index 53f124a91f0ac..58ea86dc569d5 100644
--- a/server/src/test/java/org/opensearch/repositories/fs/FsRepositoryTests.java
+++ b/server/src/test/java/org/opensearch/repositories/fs/FsRepositoryTests.java
@@ -104,6 +104,7 @@ public void testSnapshotAndRestore() throws IOException, InterruptedException {
                 .put("location", repo)
                 .put("compress", randomBoolean())
                 .put("chunk_size", randomIntBetween(100, 1000), ByteSizeUnit.BYTES)
+                .put(FsRepository.BASE_PATH_SETTING.getKey(), "my_base_path")
                 .build();
 
             int numDocs = indexDocs(directory);
diff --git a/server/src/test/java/org/opensearch/rest/RestControllerTests.java b/server/src/test/java/org/opensearch/rest/RestControllerTests.java
index bd4c7c9a4f824..c6f013985dea9 100644
--- a/server/src/test/java/org/opensearch/rest/RestControllerTests.java
+++ b/server/src/test/java/org/opensearch/rest/RestControllerTests.java
@@ -118,11 +118,9 @@ public void setup() {
                 new BytesRestResponse(RestStatus.OK, BytesRestResponse.TEXT_CONTENT_TYPE, BytesArray.EMPTY)
             )
         );
-        restController.registerHandler(
-            RestRequest.Method.GET,
-            "/error",
-            (request, channel, client) -> { throw new IllegalArgumentException("test error"); }
-        );
+        restController.registerHandler(RestRequest.Method.GET, "/error", (request, channel, client) -> {
+            throw new IllegalArgumentException("test error");
+        });
 
         httpServerTransport.start();
     }
diff --git a/server/src/test/java/org/opensearch/rest/action/cat/RestCatSegmentReplicationActionTests.java b/server/src/test/java/org/opensearch/rest/action/cat/RestCatSegmentReplicationActionTests.java
index ec2b635d2d608..7a0d80d9538ad 100644
--- a/server/src/test/java/org/opensearch/rest/action/cat/RestCatSegmentReplicationActionTests.java
+++ b/server/src/test/java/org/opensearch/rest/action/cat/RestCatSegmentReplicationActionTests.java
@@ -11,43 +11,56 @@
 import org.opensearch.action.admin.indices.replication.SegmentReplicationStatsResponse;
 import org.opensearch.action.support.DefaultShardOperationFailedException;
 import org.opensearch.cluster.node.DiscoveryNode;
+import org.opensearch.cluster.routing.AllocationId;
 import org.opensearch.cluster.routing.ShardRouting;
 import org.opensearch.common.Randomness;
 import org.opensearch.common.Table;
+import org.opensearch.common.unit.ByteSizeValue;
 import org.opensearch.common.unit.TimeValue;
 import org.opensearch.index.Index;
+import org.opensearch.index.SegmentReplicationPerGroupStats;
+import org.opensearch.index.SegmentReplicationShardStats;
 import org.opensearch.index.shard.ShardId;
 import org.opensearch.indices.replication.SegmentReplicationState;
 import org.opensearch.indices.replication.common.ReplicationLuceneIndex;
 import org.opensearch.indices.replication.common.ReplicationTimer;
 import org.opensearch.test.OpenSearchTestCase;
 
+import java.io.IOException;
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Set;
+import java.util.UUID;
 
+import static java.util.Arrays.asList;
 import static org.hamcrest.CoreMatchers.equalTo;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
 public class RestCatSegmentReplicationActionTests extends OpenSearchTestCase {
-    public void testSegmentReplicationAction() {
+    public void testSegmentReplicationAction() throws IOException {
         final RestCatSegmentReplicationAction action = new RestCatSegmentReplicationAction();
         final int totalShards = randomIntBetween(1, 32);
         final int successfulShards = Math.max(0, totalShards - randomIntBetween(1, 2));
         final int failedShards = totalShards - successfulShards;
-        final Map<String, List<SegmentReplicationState>> shardSegmentReplicationStates = new HashMap<>();
-        final List<SegmentReplicationState> segmentReplicationStates = new ArrayList<>();
+        final Map<String, List<SegmentReplicationPerGroupStats>> shardSegmentReplicationStates = new HashMap<>();
+        final List<SegmentReplicationPerGroupStats> groupStats = new ArrayList<>();
+        final long rejectedRequestCount = 5L;
 
         for (int i = 0; i < successfulShards; i++) {
+            final ShardId shardId = new ShardId(new Index("index", "_na_"), i);
             final SegmentReplicationState state = mock(SegmentReplicationState.class);
             final ShardRouting shardRouting = mock(ShardRouting.class);
             when(state.getShardRouting()).thenReturn(shardRouting);
-            when(shardRouting.shardId()).thenReturn(new ShardId(new Index("index", "_na_"), i));
+
+            when(shardRouting.shardId()).thenReturn(shardId);
+            final AllocationId aId = mock(AllocationId.class);
+            when(aId.getId()).thenReturn(UUID.randomUUID().toString());
+            when(shardRouting.allocationId()).thenReturn(aId);
             when(state.getReplicationId()).thenReturn(randomLongBetween(0, 1000));
             final ReplicationTimer timer = mock(ReplicationTimer.class);
             final long startTime = randomLongBetween(0, new Date().getTime());
@@ -60,19 +73,30 @@ public void testSegmentReplicationAction() {
             when(state.getSourceDescription()).thenReturn("Source");
             final DiscoveryNode targetNode = mock(DiscoveryNode.class);
             when(targetNode.getHostName()).thenReturn(randomAlphaOfLength(8));
+            when(targetNode.getName()).thenReturn(UUID.randomUUID().toString());
             when(state.getTargetNode()).thenReturn(targetNode);
 
             ReplicationLuceneIndex index = createTestIndex();
             when(state.getIndex()).thenReturn(index);
 
-            //
-
-            segmentReplicationStates.add(state);
+            final SegmentReplicationShardStats segmentReplicationShardStats = new SegmentReplicationShardStats(
+                state.getShardRouting().allocationId().getId(),
+                0L,
+                0L,
+                0L,
+                0L
+            );
+            segmentReplicationShardStats.setCurrentReplicationState(state);
+            final SegmentReplicationPerGroupStats perGroupStats = new SegmentReplicationPerGroupStats(
+                shardId,
+                Set.of(segmentReplicationShardStats),
+                rejectedRequestCount
+            );
+            groupStats.add(perGroupStats);
         }
 
-        final List<SegmentReplicationState> shuffle = new ArrayList<>(segmentReplicationStates);
-        Randomness.shuffle(shuffle);
-        shardSegmentReplicationStates.put("index", shuffle);
+        Randomness.shuffle(groupStats);
+        shardSegmentReplicationStates.put("index", groupStats);
 
         final List<DefaultShardOperationFailedException> shardFailures = new ArrayList<>();
         final SegmentReplicationStatsResponse response = new SegmentReplicationStatsResponse(
@@ -88,18 +112,15 @@ public void testSegmentReplicationAction() {
 
         List<Table.Cell> headers = table.getHeaders();
 
-        final List<String> expectedHeaders = Arrays.asList(
-            "index",
+        final List<String> expectedHeaders = asList(
             "shardId",
-            "time",
-            "stage",
-            "source_description",
-            "target_host",
             "target_node",
-            "files_fetched",
-            "files_percent",
-            "bytes_fetched",
-            "bytes_percent"
+            "target_host",
+            "checkpoints_behind",
+            "bytes_behind",
+            "current_lag",
+            "last_completed_lag",
+            "rejected_requests"
         );
 
         for (int i = 0; i < expectedHeaders.size(); i++) {
@@ -109,19 +130,20 @@ public void testSegmentReplicationAction() {
         assertThat(table.getRows().size(), equalTo(successfulShards));
 
         for (int i = 0; i < successfulShards; i++) {
-            final SegmentReplicationState state = segmentReplicationStates.get(i);
-            final List<Object> expectedValues = Arrays.asList(
-                "index",
-                i,
-                new TimeValue(state.getTimer().time()),
-                state.getStage().name().toLowerCase(Locale.ROOT),
-                state.getSourceDescription(),
-                state.getTargetNode().getHostName(),
-                state.getTargetNode().getName(),
-                state.getIndex().recoveredFileCount(),
-                percent(state.getIndex().recoveredFilesPercent()),
-                state.getIndex().recoveredBytes(),
-                percent(state.getIndex().recoveredBytesPercent())
+            final SegmentReplicationPerGroupStats perGroupStats = groupStats.get(i);
+            final Set<SegmentReplicationShardStats> replicaStats = perGroupStats.getReplicaStats();
+            assertEquals(1, replicaStats.size());
+            final SegmentReplicationShardStats shardStats = replicaStats.stream().findFirst().get();
+            final SegmentReplicationState currentReplicationState = shardStats.getCurrentReplicationState();
+            final List<Object> expectedValues = asList(
+                perGroupStats.getShardId(),
+                currentReplicationState.getTargetNode().getName(),
+                currentReplicationState.getTargetNode().getHostName(),
+                shardStats.getCheckpointsBehindCount(),
+                new ByteSizeValue(shardStats.getBytesBehindCount()),
+                new TimeValue(shardStats.getCurrentReplicationTimeMillis()),
+                new TimeValue(shardStats.getLastCompletedReplicationTimeMillis()),
+                rejectedRequestCount
             );
 
             final List<Table.Cell> cells = table.getRows().get(i);
diff --git a/server/src/test/java/org/opensearch/script/ScriptServiceTests.java b/server/src/test/java/org/opensearch/script/ScriptServiceTests.java
index f5fc62719564f..0485fc9935f15 100644
--- a/server/src/test/java/org/opensearch/script/ScriptServiceTests.java
+++ b/server/src/test/java/org/opensearch/script/ScriptServiceTests.java
@@ -391,10 +391,9 @@ public void testDeleteScript() throws Exception {
         assertNull(scriptMetadata.getStoredScript("_id"));
 
         ScriptMetadata errorMetadata = scriptMetadata;
-        ResourceNotFoundException e = expectThrows(
-            ResourceNotFoundException.class,
-            () -> { ScriptMetadata.deleteStoredScript(errorMetadata, "_id"); }
-        );
+        ResourceNotFoundException e = expectThrows(ResourceNotFoundException.class, () -> {
+            ScriptMetadata.deleteStoredScript(errorMetadata, "_id");
+        });
         assertEquals("stored script [_id] does not exist and cannot be deleted", e.getMessage());
     }
 
@@ -425,24 +424,17 @@ public void testGetStoredScript() throws Exception {
     public void testMaxSizeLimit() throws Exception {
         buildScriptService(Settings.builder().put(ScriptService.SCRIPT_MAX_SIZE_IN_BYTES.getKey(), 4).build());
         scriptService.compile(new Script(ScriptType.INLINE, "test", "1+1", Collections.emptyMap()), randomFrom(contexts.values()));
-        IllegalArgumentException iae = expectThrows(
-            IllegalArgumentException.class,
-            () -> {
-                scriptService.compile(
-                    new Script(ScriptType.INLINE, "test", "10+10", Collections.emptyMap()),
-                    randomFrom(contexts.values())
-                );
-            }
-        );
+        IllegalArgumentException iae = expectThrows(IllegalArgumentException.class, () -> {
+            scriptService.compile(new Script(ScriptType.INLINE, "test", "10+10", Collections.emptyMap()), randomFrom(contexts.values()));
+        });
         assertEquals("exceeded max allowed inline script size in bytes [4] with size [5] for script [10+10]", iae.getMessage());
         clusterSettings.applySettings(Settings.builder().put(ScriptService.SCRIPT_MAX_SIZE_IN_BYTES.getKey(), 6).build());
         scriptService.compile(new Script(ScriptType.INLINE, "test", "10+10", Collections.emptyMap()), randomFrom(contexts.values()));
         clusterSettings.applySettings(Settings.builder().put(ScriptService.SCRIPT_MAX_SIZE_IN_BYTES.getKey(), 5).build());
         scriptService.compile(new Script(ScriptType.INLINE, "test", "10+10", Collections.emptyMap()), randomFrom(contexts.values()));
-        iae = expectThrows(
-            IllegalArgumentException.class,
-            () -> { clusterSettings.applySettings(Settings.builder().put(ScriptService.SCRIPT_MAX_SIZE_IN_BYTES.getKey(), 2).build()); }
-        );
+        iae = expectThrows(IllegalArgumentException.class, () -> {
+            clusterSettings.applySettings(Settings.builder().put(ScriptService.SCRIPT_MAX_SIZE_IN_BYTES.getKey(), 2).build());
+        });
         assertEquals(
             "script.max_size_in_bytes cannot be set to [2], stored script [test1] exceeds the new value with a size of [3]",
             iae.getMessage()
@@ -537,10 +529,9 @@ public void testUseContextSettingValue() {
 
         assertEquals(ScriptService.SCRIPT_GENERAL_MAX_COMPILATIONS_RATE_SETTING.get(s), ScriptService.USE_CONTEXT_RATE_VALUE);
 
-        IllegalArgumentException illegal = expectThrows(
-            IllegalArgumentException.class,
-            () -> { ScriptService.SCRIPT_MAX_COMPILATIONS_RATE_SETTING.getAsMap(s); }
-        );
+        IllegalArgumentException illegal = expectThrows(IllegalArgumentException.class, () -> {
+            ScriptService.SCRIPT_MAX_COMPILATIONS_RATE_SETTING.getAsMap(s);
+        });
 
         assertEquals("parameter must contain a positive integer and a timevalue, i.e. 10/1m, but was [use-context]", illegal.getMessage());
         assertSettingDeprecationsAndWarnings(new Setting<?>[] { SCRIPT_GENERAL_MAX_COMPILATIONS_RATE_SETTING });
diff --git a/server/src/test/java/org/opensearch/search/DeletePitResponseTests.java b/server/src/test/java/org/opensearch/search/DeletePitResponseTests.java
index 5944e2a35b14a..60330f189362e 100644
--- a/server/src/test/java/org/opensearch/search/DeletePitResponseTests.java
+++ b/server/src/test/java/org/opensearch/search/DeletePitResponseTests.java
@@ -43,7 +43,7 @@ public void testDeletePitResponseToXContent() throws IOException {
     public void testDeletePitResponseToAndFromXContent() throws IOException {
         XContentType xContentType = randomFrom(XContentType.values());
         DeletePitResponse originalResponse = createDeletePitResponseTestItem();
-        ;
+
         BytesReference originalBytes = toShuffledXContent(originalResponse, xContentType, ToXContent.EMPTY_PARAMS, randomBoolean());
         DeletePitResponse parsedResponse;
         try (XContentParser parser = createParser(xContentType.xContent(), originalBytes)) {
diff --git a/server/src/test/java/org/opensearch/search/DocValueFormatTests.java b/server/src/test/java/org/opensearch/search/DocValueFormatTests.java
index bd0fbfe69960c..961b7bc3dec3f 100644
--- a/server/src/test/java/org/opensearch/search/DocValueFormatTests.java
+++ b/server/src/test/java/org/opensearch/search/DocValueFormatTests.java
@@ -76,6 +76,7 @@ public void testSerialization() throws Exception {
         DocValueFormat vf = in.readNamedWriteable(DocValueFormat.class);
         assertEquals(DocValueFormat.Decimal.class, vf.getClass());
         assertEquals("###.##", ((DocValueFormat.Decimal) vf).pattern);
+        assertEquals(decimalFormat, vf);
 
         DateFormatter formatter = DateFormatter.forPattern("epoch_second");
         DocValueFormat.DateTime dateFormat = new DocValueFormat.DateTime(formatter, ZoneOffset.ofHours(1), Resolution.MILLISECONDS);
@@ -87,6 +88,7 @@ public void testSerialization() throws Exception {
         assertEquals("epoch_second", ((DocValueFormat.DateTime) vf).formatter.pattern());
         assertEquals(ZoneOffset.ofHours(1), ((DocValueFormat.DateTime) vf).timeZone);
         assertEquals(Resolution.MILLISECONDS, ((DocValueFormat.DateTime) vf).resolution);
+        assertEquals(dateFormat, vf);
 
         DocValueFormat.DateTime nanosDateFormat = new DocValueFormat.DateTime(formatter, ZoneOffset.ofHours(1), Resolution.NANOSECONDS);
         out = new BytesStreamOutput();
@@ -97,6 +99,7 @@ public void testSerialization() throws Exception {
         assertEquals("epoch_second", ((DocValueFormat.DateTime) vf).formatter.pattern());
         assertEquals(ZoneOffset.ofHours(1), ((DocValueFormat.DateTime) vf).timeZone);
         assertEquals(Resolution.NANOSECONDS, ((DocValueFormat.DateTime) vf).resolution);
+        assertEquals(nanosDateFormat, vf);
 
         out = new BytesStreamOutput();
         out.writeNamedWriteable(DocValueFormat.GEOHASH);
@@ -230,4 +233,23 @@ public void testDecimalParse() {
         assertEquals(0.859d, parser.parseDouble("0.859", true, null), 0.0d);
         assertEquals(0.8598023539251286d, parser.parseDouble("0.8598023539251286", true, null), 0.0d);
     }
+
+    public void testLongParse() {
+        assertEquals(DocValueFormat.RAW.format(0), 0L);
+        assertEquals(DocValueFormat.RAW.format(-1), -1L);
+        assertEquals(DocValueFormat.RAW.format(1), 1L);
+        assertEquals(DocValueFormat.RAW.format(0d), 0d);
+        assertEquals(DocValueFormat.RAW.format(9.5d), 9.5d);
+        assertEquals(DocValueFormat.RAW.format(-1d), -1d);
+    }
+
+    public void testGeoTileParse() {
+        assertEquals(DocValueFormat.GEOTILE.format(longEncode(0, 0, 0)), "0/0/0");
+        assertEquals(DocValueFormat.GEOTILE.format(longEncode(30, 70, 15)), "15/19114/7333");
+        assertEquals(DocValueFormat.GEOTILE.format(longEncode(179.999, 89.999, 29)), "29/536869420/0");
+        assertEquals(DocValueFormat.GEOTILE.format(longEncode(-179.999, -89.999, 29)), "29/1491/536870911");
+        assertEquals(DocValueFormat.GEOTILE.format(longEncode(1, 1, 2)), "2/2/1");
+        assertEquals(DocValueFormat.GEOTILE.format(longEncode(13, 95, 1)), "1/1/0");
+        assertEquals(DocValueFormat.GEOTILE.format(longEncode(13, -95, 1)), "1/1/1");
+    }
 }
diff --git a/server/src/test/java/org/opensearch/search/SearchServiceTests.java b/server/src/test/java/org/opensearch/search/SearchServiceTests.java
index 1f824d40eb638..7c341c9d3cc43 100644
--- a/server/src/test/java/org/opensearch/search/SearchServiceTests.java
+++ b/server/src/test/java/org/opensearch/search/SearchServiceTests.java
@@ -740,13 +740,9 @@ public void testOpenScrollContextsConcurrently() throws Exception {
     public static class FailOnRewriteQueryPlugin extends Plugin implements SearchPlugin {
         @Override
         public List<QuerySpec<?>> getQueries() {
-            return singletonList(
-                new QuerySpec<>(
-                    "fail_on_rewrite_query",
-                    FailOnRewriteQueryBuilder::new,
-                    parseContext -> { throw new UnsupportedOperationException("No query parser for this plugin"); }
-                )
-            );
+            return singletonList(new QuerySpec<>("fail_on_rewrite_query", FailOnRewriteQueryBuilder::new, parseContext -> {
+                throw new UnsupportedOperationException("No query parser for this plugin");
+            }));
         }
     }
 
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/MergingBucketsDeferringCollectorTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/MergingBucketsDeferringCollectorTests.java
index 051056f7e0fdc..21e08b034f1d0 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/MergingBucketsDeferringCollectorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/MergingBucketsDeferringCollectorTests.java
@@ -73,16 +73,7 @@ public void collect(int doc, long owningBucketOrd) throws IOException {
         }, (deferringCollector, finalCollector) -> {
             deferringCollector.prepareSelectedBuckets(0, 8, 9);
 
-            equalTo(
-                org.opensearch.common.collect.Map.of(
-                    0L,
-                    org.opensearch.common.collect.List.of(0, 1, 2, 3, 4, 5, 6, 7),
-                    1L,
-                    org.opensearch.common.collect.List.of(8),
-                    2L,
-                    org.opensearch.common.collect.List.of(9)
-                )
-            );
+            equalTo(Map.of(0L, List.of(0, 1, 2, 3, 4, 5, 6, 7), 1L, List.of(8), 2L, List.of(9)));
         });
     }
 
@@ -99,19 +90,7 @@ public void collect(int doc, long owningBucketOrd) throws IOException {
         }, (deferringCollector, finalCollector) -> {
             deferringCollector.prepareSelectedBuckets(0, 8, 9);
 
-            assertThat(
-                finalCollector.collection,
-                equalTo(
-                    org.opensearch.common.collect.Map.of(
-                        0L,
-                        org.opensearch.common.collect.List.of(4, 5, 6, 7),
-                        1L,
-                        org.opensearch.common.collect.List.of(8),
-                        2L,
-                        org.opensearch.common.collect.List.of(9)
-                    )
-                )
-            );
+            assertThat(finalCollector.collection, equalTo(Map.of(0L, List.of(4, 5, 6, 7), 1L, List.of(8), 2L, List.of(9))));
         });
     }
 
@@ -129,19 +108,7 @@ public void collect(int doc, long owningBucketOrd) throws IOException {
         }, (deferringCollector, finalCollector) -> {
             deferringCollector.prepareSelectedBuckets(0, 8, 9);
 
-            assertThat(
-                finalCollector.collection,
-                equalTo(
-                    org.opensearch.common.collect.Map.of(
-                        0L,
-                        org.opensearch.common.collect.List.of(0, 1, 2, 3),
-                        1L,
-                        org.opensearch.common.collect.List.of(8),
-                        2L,
-                        org.opensearch.common.collect.List.of(9)
-                    )
-                )
-            );
+            assertThat(finalCollector.collection, equalTo(Map.of(0L, List.of(0, 1, 2, 3), 1L, List.of(8), 2L, List.of(9))));
         });
     }
 
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/composite/CompositeAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/composite/CompositeAggregatorTests.java
index 25003e0b84567..eabc4b7764eed 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/composite/CompositeAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/composite/CompositeAggregatorTests.java
@@ -89,7 +89,9 @@ public void testUnmappedFieldWithTerms() throws Exception {
             Arrays.asList(new MatchAllDocsQuery(), new DocValuesFieldExistsQuery("keyword")),
             dataset,
             () -> new CompositeAggregationBuilder("name", Arrays.asList(new TermsValuesSourceBuilder("unmapped").field("unmapped"))),
-            (result) -> { assertEquals(0, result.getBuckets().size()); }
+            (result) -> {
+                assertEquals(0, result.getBuckets().size());
+            }
         );
 
         testSearchCase(
@@ -114,7 +116,9 @@ public void testUnmappedFieldWithTerms() throws Exception {
                 "name",
                 Arrays.asList(new TermsValuesSourceBuilder("unmapped").field("unmapped").missingBucket(true))
             ).aggregateAfter(Collections.singletonMap("unmapped", null)),
-            (result) -> { assertEquals(0, result.getBuckets().size()); }
+            (result) -> {
+                assertEquals(0, result.getBuckets().size());
+            }
         );
 
         testSearchCase(
@@ -127,7 +131,9 @@ public void testUnmappedFieldWithTerms() throws Exception {
                     new TermsValuesSourceBuilder("unmapped").field("unmapped")
                 )
             ),
-            (result) -> { assertEquals(0, result.getBuckets().size()); }
+            (result) -> {
+                assertEquals(0, result.getBuckets().size());
+            }
         );
 
         testSearchCase(
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/filter/InternalFilterTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/filter/InternalFilterTests.java
index b856a81515b52..110773a82404d 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/filter/InternalFilterTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/filter/InternalFilterTests.java
@@ -92,7 +92,7 @@ public InternalAggregation reduce(InternalAggregation aggregation, ReduceContext
             }
         };
         PipelineTree tree = new PipelineTree(
-            org.opensearch.common.collect.Map.of(inner.getName(), new PipelineTree(emptyMap(), singletonList(mockPipeline))),
+            Map.of(inner.getName(), new PipelineTree(emptyMap(), singletonList(mockPipeline))),
             emptyList()
         );
         InternalFilter reduced = (InternalFilter) test.reducePipelines(test, emptyReduceContextBuilder().forFinalReduction(), tree);
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/filter/InternalFiltersTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/filter/InternalFiltersTests.java
index 176bfefdefc1e..038efc9f7c4f4 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/filter/InternalFiltersTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/filter/InternalFiltersTests.java
@@ -156,7 +156,7 @@ public InternalAggregation reduce(InternalAggregation aggregation, ReduceContext
             }
         };
         PipelineTree tree = new PipelineTree(
-            org.opensearch.common.collect.Map.of(inner.getName(), new PipelineTree(emptyMap(), singletonList(mockPipeline))),
+            Map.of(inner.getName(), new PipelineTree(emptyMap(), singletonList(mockPipeline))),
             emptyList()
         );
         InternalFilters reduced = (InternalFilters) test.reducePipelines(test, emptyReduceContextBuilder().forFinalReduction(), tree);
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/AutoDateHistogramAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/AutoDateHistogramAggregatorTests.java
index 0f49e02febabe..315f148ad5a02 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/AutoDateHistogramAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/AutoDateHistogramAggregatorTests.java
@@ -305,7 +305,7 @@ public void testAsSubAggWithIncreasedRounding() throws IOException {
             int n = 0;
             for (long d = start; d < end; d += anHour) {
                 docs.add(
-                    org.opensearch.common.collect.List.of(
+                    List.of(
                         new SortedNumericDocValuesField(AGGREGABLE_DATE, d),
                         new SortedSetDocValuesField("k1", aBytes),
                         new SortedSetDocValuesField("k1", d < useC ? bBytes : cBytes),
@@ -373,12 +373,7 @@ public void testAsSubAggInManyBuckets() throws IOException {
             List<List<IndexableField>> docs = new ArrayList<>();
             int n = 0;
             for (long d = start; d < end; d += anHour) {
-                docs.add(
-                    org.opensearch.common.collect.List.of(
-                        new SortedNumericDocValuesField(AGGREGABLE_DATE, d),
-                        new SortedNumericDocValuesField("n", n % 100)
-                    )
-                );
+                docs.add(List.of(new SortedNumericDocValuesField(AGGREGABLE_DATE, d), new SortedNumericDocValuesField("n", n % 100)));
                 n++;
             }
             /*
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregatorTestCase.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregatorTestCase.java
index ff9122aa42326..f3cda87342c18 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregatorTestCase.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregatorTestCase.java
@@ -48,6 +48,7 @@
 
 import java.io.IOException;
 import java.util.Collections;
+import java.util.List;
 import java.util.function.Consumer;
 
 public abstract class DateHistogramAggregatorTestCase extends AggregatorTestCase {
@@ -63,7 +64,7 @@ protected final <R extends InternalAggregation> void asSubAggTestCase(Aggregatio
         throws IOException {
         CheckedBiConsumer<RandomIndexWriter, DateFieldMapper.DateFieldType, IOException> buildIndex = (iw, dft) -> {
             iw.addDocument(
-                org.opensearch.common.collect.List.of(
+                List.of(
                     new SortedNumericDocValuesField(AGGREGABLE_DATE, dft.parse("2020-02-01T00:00:00Z")),
                     new SortedSetDocValuesField("k1", new BytesRef("a")),
                     new SortedSetDocValuesField("k2", new BytesRef("a")),
@@ -71,7 +72,7 @@ protected final <R extends InternalAggregation> void asSubAggTestCase(Aggregatio
                 )
             );
             iw.addDocument(
-                org.opensearch.common.collect.List.of(
+                List.of(
                     new SortedNumericDocValuesField(AGGREGABLE_DATE, dft.parse("2020-03-01T00:00:00Z")),
                     new SortedSetDocValuesField("k1", new BytesRef("a")),
                     new SortedSetDocValuesField("k2", new BytesRef("a")),
@@ -79,7 +80,7 @@ protected final <R extends InternalAggregation> void asSubAggTestCase(Aggregatio
                 )
             );
             iw.addDocument(
-                org.opensearch.common.collect.List.of(
+                List.of(
                     new SortedNumericDocValuesField(AGGREGABLE_DATE, dft.parse("2021-02-01T00:00:00Z")),
                     new SortedSetDocValuesField("k1", new BytesRef("a")),
                     new SortedSetDocValuesField("k2", new BytesRef("a")),
@@ -87,7 +88,7 @@ protected final <R extends InternalAggregation> void asSubAggTestCase(Aggregatio
                 )
             );
             iw.addDocument(
-                org.opensearch.common.collect.List.of(
+                List.of(
                     new SortedNumericDocValuesField(AGGREGABLE_DATE, dft.parse("2021-03-01T00:00:00Z")),
                     new SortedSetDocValuesField("k1", new BytesRef("a")),
                     new SortedSetDocValuesField("k2", new BytesRef("b")),
@@ -95,7 +96,7 @@ protected final <R extends InternalAggregation> void asSubAggTestCase(Aggregatio
                 )
             );
             iw.addDocument(
-                org.opensearch.common.collect.List.of(
+                List.of(
                     new SortedNumericDocValuesField(AGGREGABLE_DATE, dft.parse("2020-02-01T00:00:00Z")),
                     new SortedSetDocValuesField("k1", new BytesRef("b")),
                     new SortedSetDocValuesField("k2", new BytesRef("b")),
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregatorTests.java
index 597175d89bcfe..7bd39c72ae325 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/DateHistogramAggregatorTests.java
@@ -193,14 +193,14 @@ public void testAsSubAgg() throws IOException {
             InternalDateHistogram adh = a.getAggregations().get("dh");
             assertThat(
                 adh.getBuckets().stream().map(bucket -> bucket.getKey().toString()).collect(toList()),
-                equalTo(org.opensearch.common.collect.List.of("2020-01-01T00:00Z", "2021-01-01T00:00Z"))
+                equalTo(List.of("2020-01-01T00:00Z", "2021-01-01T00:00Z"))
             );
 
             StringTerms.Bucket b = terms.getBucketByKey("b");
             InternalDateHistogram bdh = b.getAggregations().get("dh");
             assertThat(
                 bdh.getBuckets().stream().map(bucket -> bucket.getKey().toString()).collect(toList()),
-                equalTo(org.opensearch.common.collect.List.of("2020-01-01T00:00Z"))
+                equalTo(List.of("2020-01-01T00:00Z"))
             );
         });
         builder = new TermsAggregationBuilder("k2").field("k2").subAggregation(builder);
@@ -211,7 +211,7 @@ public void testAsSubAgg() throws IOException {
             InternalDateHistogram ak1adh = ak1a.getAggregations().get("dh");
             assertThat(
                 ak1adh.getBuckets().stream().map(bucket -> bucket.getKey().toString()).collect(toList()),
-                equalTo(org.opensearch.common.collect.List.of("2020-01-01T00:00Z", "2021-01-01T00:00Z"))
+                equalTo(List.of("2020-01-01T00:00Z", "2021-01-01T00:00Z"))
             );
 
             StringTerms.Bucket b = terms.getBucketByKey("b");
@@ -220,13 +220,13 @@ public void testAsSubAgg() throws IOException {
             InternalDateHistogram bk1adh = bk1a.getAggregations().get("dh");
             assertThat(
                 bk1adh.getBuckets().stream().map(bucket -> bucket.getKey().toString()).collect(toList()),
-                equalTo(org.opensearch.common.collect.List.of("2021-01-01T00:00Z"))
+                equalTo(List.of("2021-01-01T00:00Z"))
             );
             StringTerms.Bucket bk1b = bk1.getBucketByKey("b");
             InternalDateHistogram bk1bdh = bk1b.getAggregations().get("dh");
             assertThat(
                 bk1bdh.getBuckets().stream().map(bucket -> bucket.getKey().toString()).collect(toList()),
-                equalTo(org.opensearch.common.collect.List.of("2020-01-01T00:00Z"))
+                equalTo(List.of("2020-01-01T00:00Z"))
             );
         });
     }
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/NumericHistogramAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/NumericHistogramAggregatorTests.java
index e7b22a9a57476..bb9ed263ca3f6 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/NumericHistogramAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/NumericHistogramAggregatorTests.java
@@ -303,10 +303,9 @@ public void testIncorrectFieldType() throws Exception {
             try (IndexReader reader = w.getReader()) {
                 IndexSearcher searcher = new IndexSearcher(reader);
 
-                expectThrows(
-                    IllegalArgumentException.class,
-                    () -> { searchAndReduce(searcher, new MatchAllDocsQuery(), aggBuilder, keywordField("field")); }
-                );
+                expectThrows(IllegalArgumentException.class, () -> {
+                    searchAndReduce(searcher, new MatchAllDocsQuery(), aggBuilder, keywordField("field"));
+                });
             }
         }
 
@@ -420,7 +419,7 @@ public void testAsSubAgg() throws IOException {
             List<List<IndexableField>> docs = new ArrayList<>();
             for (int n = 0; n < 10000; n++) {
                 docs.add(
-                    org.opensearch.common.collect.List.of(
+                    List.of(
                         new SortedNumericDocValuesField("outer", n % 100),
                         new SortedNumericDocValuesField("inner", n / 100),
                         new SortedNumericDocValuesField("n", n)
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/RangeHistogramAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/RangeHistogramAggregatorTests.java
index 41bd0d77bff00..3ee9765e445fd 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/RangeHistogramAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/RangeHistogramAggregatorTests.java
@@ -492,14 +492,14 @@ public void testAsSubAgg() throws IOException {
             List<List<IndexableField>> docs = new ArrayList<>();
             for (int n = 0; n < 10000; n++) {
                 BytesRef outerRange = RangeType.LONG.encodeRanges(
-                    org.opensearch.common.collect.Set.of(new RangeFieldMapper.Range(RangeType.LONG, n % 100, n % 100 + 10, true, true))
+                    Set.of(new RangeFieldMapper.Range(RangeType.LONG, n % 100, n % 100 + 10, true, true))
                 );
                 BytesRef innerRange = RangeType.LONG.encodeRanges(
-                    org.opensearch.common.collect.Set.of(new RangeFieldMapper.Range(RangeType.LONG, n / 100, n / 100 + 10, true, true))
+                    Set.of(new RangeFieldMapper.Range(RangeType.LONG, n / 100, n / 100 + 10, true, true))
                 );
 
                 docs.add(
-                    org.opensearch.common.collect.List.of(
+                    List.of(
                         new BinaryDocValuesField("outer", outerRange),
                         new BinaryDocValuesField("inner", innerRange),
                         new SortedNumericDocValuesField("n", n)
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/VariableWidthHistogramAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/VariableWidthHistogramAggregatorTests.java
index b1d62f3402bc3..33f2a0b56b5ba 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/VariableWidthHistogramAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/histogram/VariableWidthHistogramAggregatorTests.java
@@ -493,22 +493,12 @@ public void testAsSubAggregation() throws IOException {
         AggregationBuilder builder = new TermsAggregationBuilder("t").field("t")
             .subAggregation(new VariableWidthHistogramAggregationBuilder("v").field("v").setNumBuckets(2));
         CheckedConsumer<RandomIndexWriter, IOException> buildIndex = iw -> {
-            iw.addDocument(
-                org.opensearch.common.collect.List.of(new SortedNumericDocValuesField("t", 1), new SortedNumericDocValuesField("v", 1))
-            );
-            iw.addDocument(
-                org.opensearch.common.collect.List.of(new SortedNumericDocValuesField("t", 1), new SortedNumericDocValuesField("v", 10))
-            );
-            iw.addDocument(
-                org.opensearch.common.collect.List.of(new SortedNumericDocValuesField("t", 1), new SortedNumericDocValuesField("v", 11))
-            );
+            iw.addDocument(List.of(new SortedNumericDocValuesField("t", 1), new SortedNumericDocValuesField("v", 1)));
+            iw.addDocument(List.of(new SortedNumericDocValuesField("t", 1), new SortedNumericDocValuesField("v", 10)));
+            iw.addDocument(List.of(new SortedNumericDocValuesField("t", 1), new SortedNumericDocValuesField("v", 11)));
 
-            iw.addDocument(
-                org.opensearch.common.collect.List.of(new SortedNumericDocValuesField("t", 2), new SortedNumericDocValuesField("v", 20))
-            );
-            iw.addDocument(
-                org.opensearch.common.collect.List.of(new SortedNumericDocValuesField("t", 2), new SortedNumericDocValuesField("v", 30))
-            );
+            iw.addDocument(List.of(new SortedNumericDocValuesField("t", 2), new SortedNumericDocValuesField("v", 20)));
+            iw.addDocument(List.of(new SortedNumericDocValuesField("t", 2), new SortedNumericDocValuesField("v", 30)));
         };
         Consumer<LongTerms> verify = terms -> {
             /*
@@ -520,14 +510,14 @@ public void testAsSubAggregation() throws IOException {
             InternalVariableWidthHistogram v1 = t1.getAggregations().get("v");
             assertThat(
                 v1.getBuckets().stream().map(InternalVariableWidthHistogram.Bucket::centroid).collect(toList()),
-                equalTo(org.opensearch.common.collect.List.of(1.0, 10.5))
+                equalTo(List.of(1.0, 10.5))
             );
 
             LongTerms.Bucket t2 = terms.getBucketByKey("1");
             InternalVariableWidthHistogram v2 = t2.getAggregations().get("v");
             assertThat(
                 v2.getBuckets().stream().map(InternalVariableWidthHistogram.Bucket::centroid).collect(toList()),
-                equalTo(org.opensearch.common.collect.List.of(20.0, 30))
+                equalTo(List.of(20.0, 30))
             );
         };
         Exception e = expectThrows(
@@ -550,10 +540,12 @@ public void testSmallShardSize() throws Exception {
             IllegalArgumentException.class,
             () -> testSearchCase(
                 DEFAULT_QUERY,
-                org.opensearch.common.collect.List.of(),
+                List.of(),
                 true,
                 aggregation -> aggregation.field(NUMERIC_FIELD).setNumBuckets(2).setShardSize(2),
-                histogram -> { fail(); }
+                histogram -> {
+                    fail();
+                }
             )
         );
         assertThat(e.getMessage(), equalTo("3/4 of shard_size must be at least buckets but was [1<2] for [_name]"));
@@ -568,7 +560,7 @@ public void testHugeShardSize() throws Exception {
             aggregation -> aggregation.field(NUMERIC_FIELD).setShardSize(1000000000),
             histogram -> assertThat(
                 histogram.getBuckets().stream().map(InternalVariableWidthHistogram.Bucket::getKey).collect(toList()),
-                equalTo(org.opensearch.common.collect.List.of(1.0, 2.0, 3.0))
+                equalTo(List.of(1.0, 2.0, 3.0))
             )
         );
     }
@@ -578,10 +570,12 @@ public void testSmallInitialBuffer() throws Exception {
             IllegalArgumentException.class,
             () -> testSearchCase(
                 DEFAULT_QUERY,
-                org.opensearch.common.collect.List.of(),
+                List.of(),
                 true,
                 aggregation -> aggregation.field(NUMERIC_FIELD).setInitialBuffer(1),
-                histogram -> { fail(); }
+                histogram -> {
+                    fail();
+                }
             )
         );
         assertThat(e.getMessage(), equalTo("initial_buffer must be at least buckets but was [1<10] for [_name]"));
@@ -597,7 +591,7 @@ public void testOutOfOrderInitialBuffer() throws Exception {
             histogram -> {
                 assertThat(
                     histogram.getBuckets().stream().map(InternalVariableWidthHistogram.Bucket::getKey).collect(toList()),
-                    equalTo(org.opensearch.common.collect.List.of(1.0, 2.0, 3.0))
+                    equalTo(List.of(1.0, 2.0, 3.0))
                 );
             }
         );
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/missing/MissingAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/missing/MissingAggregatorTests.java
index e888972b8e447..c544dcce45cce 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/missing/MissingAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/missing/MissingAggregatorTests.java
@@ -120,7 +120,7 @@ public void testMatchAllDocs() throws IOException {
         }, internalMissing -> {
             assertEquals(numDocs, internalMissing.getDocCount());
             assertTrue(AggregationInspectionHelper.hasValue(internalMissing));
-        }, org.opensearch.common.collect.List.of(aggFieldType, anotherFieldType));
+        }, List.of(aggFieldType, anotherFieldType));
     }
 
     public void testMatchSparse() throws IOException {
@@ -145,7 +145,7 @@ public void testMatchSparse() throws IOException {
         testCase(newMatchAllQuery(), builder, writer -> writer.addDocuments(docs), internalMissing -> {
             assertEquals(finalDocsMissingAggField, internalMissing.getDocCount());
             assertTrue(AggregationInspectionHelper.hasValue(internalMissing));
-        }, org.opensearch.common.collect.List.of(aggFieldType, anotherFieldType));
+        }, List.of(aggFieldType, anotherFieldType));
     }
 
     public void testMatchSparseRangeField() throws IOException {
@@ -225,7 +225,7 @@ public void testMissingParam() throws IOException {
         }, internalMissing -> {
             assertEquals(0, internalMissing.getDocCount());
             assertFalse(AggregationInspectionHelper.hasValue(internalMissing));
-        }, org.opensearch.common.collect.List.of(aggFieldType, anotherFieldType));
+        }, List.of(aggFieldType, anotherFieldType));
     }
 
     public void testMultiValuedField() throws IOException {
@@ -241,7 +241,7 @@ public void testMultiValuedField() throws IOException {
             if (randomBoolean()) {
                 final long randomLong = randomLong();
                 docs.add(
-                    org.opensearch.common.collect.Set.of(
+                    Set.of(
                         new SortedNumericDocValuesField(aggFieldType.name(), randomLong),
                         new SortedNumericDocValuesField(aggFieldType.name(), randomLong + 1)
                     )
@@ -256,7 +256,7 @@ public void testMultiValuedField() throws IOException {
         testCase(newMatchAllQuery(), builder, writer -> writer.addDocuments(docs), internalMissing -> {
             assertEquals(finalDocsMissingAggField, internalMissing.getDocCount());
             assertTrue(AggregationInspectionHelper.hasValue(internalMissing));
-        }, org.opensearch.common.collect.List.of(aggFieldType, anotherFieldType));
+        }, List.of(aggFieldType, anotherFieldType));
     }
 
     public void testSingleValuedFieldWithValueScript() throws IOException {
@@ -289,12 +289,12 @@ private void valueScriptTestCase(Script script) throws IOException {
         testCase(newMatchAllQuery(), builder, writer -> writer.addDocuments(docs), internalMissing -> {
             assertEquals(finalDocsMissingField, internalMissing.getDocCount());
             assertTrue(AggregationInspectionHelper.hasValue(internalMissing));
-        }, org.opensearch.common.collect.List.of(aggFieldType, anotherFieldType));
+        }, List.of(aggFieldType, anotherFieldType));
     }
 
     public void testMultiValuedFieldWithFieldScriptWithParams() throws IOException {
         final long threshold = 10;
-        final Map<String, Object> params = org.opensearch.common.collect.Map.of("field", "agg_field", "threshold", threshold);
+        final Map<String, Object> params = Map.of("field", "agg_field", "threshold", threshold);
         fieldScriptTestCase(new Script(ScriptType.INLINE, MockScriptEngine.NAME, FIELD_SCRIPT_PARAMS, params), threshold);
     }
 
@@ -320,7 +320,7 @@ private void fieldScriptTestCase(Script script, long threshold) throws IOExcepti
                 docsBelowThreshold++;
             }
             docs.add(
-                org.opensearch.common.collect.Set.of(
+                Set.of(
                     new SortedNumericDocValuesField(aggFieldType.name(), firstValue),
                     new SortedNumericDocValuesField(aggFieldType.name(), secondValue)
                 )
@@ -362,7 +362,7 @@ protected AggregationBuilder createAggBuilderForTypeTest(MappedFieldType fieldTy
 
     @Override
     protected List<ValuesSourceType> getSupportedValuesSourceTypes() {
-        return org.opensearch.common.collect.List.of(
+        return List.of(
             CoreValuesSourceType.NUMERIC,
             CoreValuesSourceType.BYTES,
             CoreValuesSourceType.GEOPOINT,
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/range/DateRangeAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/range/DateRangeAggregatorTests.java
index e6d7230aa6cb0..9a2ef3de1dfe4 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/range/DateRangeAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/range/DateRangeAggregatorTests.java
@@ -220,13 +220,9 @@ public void testKeywordField() {
 
         IllegalArgumentException e = expectThrows(
             IllegalArgumentException.class,
-            () -> testCase(
-                aggregationBuilder,
-                new MatchAllDocsQuery(),
-                iw -> { iw.addDocument(singleton(new SortedSetDocValuesField("string", new BytesRef("foo")))); },
-                range -> fail("Should have thrown exception"),
-                fieldType
-            )
+            () -> testCase(aggregationBuilder, new MatchAllDocsQuery(), iw -> {
+                iw.addDocument(singleton(new SortedSetDocValuesField("string", new BytesRef("foo"))));
+            }, range -> fail("Should have thrown exception"), fieldType)
         );
         assertEquals("Field [not_a_number] of type [keyword] is not supported for aggregation [date_range]", e.getMessage());
     }
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/range/RangeAggregationBuilderTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/range/RangeAggregationBuilderTests.java
index ef5af0b496113..a88d96a7a7614 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/range/RangeAggregationBuilderTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/range/RangeAggregationBuilderTests.java
@@ -128,6 +128,6 @@ public void testNumericKeys() throws IOException {
         );
         assertThat(builder.getName(), equalTo("test"));
         assertThat(builder.field(), equalTo("f"));
-        assertThat(builder.ranges, equalTo(org.opensearch.common.collect.List.of(new RangeAggregator.Range("1", null, 0d))));
+        assertThat(builder.ranges, equalTo(List.of(new RangeAggregator.Range("1", null, 0d))));
     }
 }
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/range/RangeAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/range/RangeAggregatorTests.java
index f1be4d1ede930..8b9bd388eb641 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/range/RangeAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/range/RangeAggregatorTests.java
@@ -245,13 +245,9 @@ public void testUnsupportedType() {
 
         IllegalArgumentException e = expectThrows(
             IllegalArgumentException.class,
-            () -> testCase(
-                aggregationBuilder,
-                new MatchAllDocsQuery(),
-                iw -> { iw.addDocument(singleton(new SortedSetDocValuesField("string", new BytesRef("foo")))); },
-                range -> fail("Should have thrown exception"),
-                fieldType
-            )
+            () -> testCase(aggregationBuilder, new MatchAllDocsQuery(), iw -> {
+                iw.addDocument(singleton(new SortedSetDocValuesField("string", new BytesRef("foo"))));
+            }, range -> fail("Should have thrown exception"), fieldType)
         );
         assertEquals("Field [not_a_number] of type [keyword] is not supported for aggregation [range]", e.getMessage());
     }
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregationBuilderTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregationBuilderTests.java
index 505fb7382ab3b..c0b2b55fefeda 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregationBuilderTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregationBuilderTests.java
@@ -91,10 +91,9 @@ protected MultiTermsAggregationBuilder createTestAggregatorBuilder() {
     }
 
     public void testInvalidTermsParams() {
-        IllegalArgumentException exception = expectThrows(
-            IllegalArgumentException.class,
-            () -> { new MultiTermsAggregationBuilder("_name").terms(Collections.singletonList(randomFieldConfig())); }
-        );
+        IllegalArgumentException exception = expectThrows(IllegalArgumentException.class, () -> {
+            new MultiTermsAggregationBuilder("_name").terms(Collections.singletonList(randomFieldConfig()));
+        });
         assertEquals(
             "multi term aggregation must has at least 2 terms. Found [1] in [_name] Use terms aggregation for single term aggregation",
             exception.getMessage()
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregatorTests.java
index f3922a65ff264..75ad9e12e0776 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/terms/MultiTermsAggregatorTests.java
@@ -127,7 +127,7 @@ protected AggregationBuilder createAggBuilderForTypeTest(MappedFieldType fieldTy
 
     @Override
     protected ScriptService getMockScriptService() {
-        final Map<String, Function<Map<String, Object>, Object>> scripts = org.opensearch.common.collect.Map.of(
+        final Map<String, Function<Map<String, Object>, Object>> scripts = Map.of(
             VALUE_SCRIPT_NAME,
             vars -> ((Number) vars.get("_value")).doubleValue() + 1,
             FIELD_SCRIPT_NAME,
diff --git a/server/src/test/java/org/opensearch/search/aggregations/bucket/terms/RareTermsAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/bucket/terms/RareTermsAggregatorTests.java
index 678bc2fc6f536..debe4d343e874 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/bucket/terms/RareTermsAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/bucket/terms/RareTermsAggregatorTests.java
@@ -376,25 +376,13 @@ public void testInsideTerms() throws IOException {
 
             StringTerms.Bucket even = terms.getBucketByKey("even");
             InternalRareTerms<?, ?> evenRare = even.getAggregations().get("rare");
-            assertEquals(
-                evenRare.getBuckets().stream().map(InternalRareTerms.Bucket::getKeyAsString).collect(toList()),
-                org.opensearch.common.collect.List.of("2")
-            );
-            assertEquals(
-                evenRare.getBuckets().stream().map(InternalRareTerms.Bucket::getDocCount).collect(toList()),
-                org.opensearch.common.collect.List.of(2L)
-            );
+            assertEquals(evenRare.getBuckets().stream().map(InternalRareTerms.Bucket::getKeyAsString).collect(toList()), List.of("2"));
+            assertEquals(evenRare.getBuckets().stream().map(InternalRareTerms.Bucket::getDocCount).collect(toList()), List.of(2L));
 
             StringTerms.Bucket odd = terms.getBucketByKey("odd");
             InternalRareTerms<?, ?> oddRare = odd.getAggregations().get("rare");
-            assertEquals(
-                oddRare.getBuckets().stream().map(InternalRareTerms.Bucket::getKeyAsString).collect(toList()),
-                org.opensearch.common.collect.List.of("1")
-            );
-            assertEquals(
-                oddRare.getBuckets().stream().map(InternalRareTerms.Bucket::getDocCount).collect(toList()),
-                org.opensearch.common.collect.List.of(1L)
-            );
+            assertEquals(oddRare.getBuckets().stream().map(InternalRareTerms.Bucket::getKeyAsString).collect(toList()), List.of("1"));
+            assertEquals(oddRare.getBuckets().stream().map(InternalRareTerms.Bucket::getDocCount).collect(toList()), List.of(1L));
         }
     }
 
diff --git a/server/src/test/java/org/opensearch/search/aggregations/metrics/HDRPercentilesAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/metrics/HDRPercentilesAggregatorTests.java
index bbf7f6cfd9cc2..e08ac840e1785 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/metrics/HDRPercentilesAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/metrics/HDRPercentilesAggregatorTests.java
@@ -113,16 +113,9 @@ public void testRangeField() throws IOException {
         MappedFieldType fieldType = new RangeFieldMapper.RangeFieldType(fieldName, RangeType.DOUBLE);
         RangeFieldMapper.Range range = new RangeFieldMapper.Range(RangeType.DOUBLE, 1.0D, 5.0D, true, true);
         BytesRef encodedRange = RangeType.DOUBLE.encodeRanges(Collections.singleton(range));
-        expectThrows(
-            IllegalArgumentException.class,
-            () -> testCase(
-                new DocValuesFieldExistsQuery(fieldName),
-                iw -> { iw.addDocument(singleton(new BinaryDocValuesField(fieldName, encodedRange))); },
-                hdr -> {},
-                fieldType,
-                fieldName
-            )
-        );
+        expectThrows(IllegalArgumentException.class, () -> testCase(new DocValuesFieldExistsQuery(fieldName), iw -> {
+            iw.addDocument(singleton(new BinaryDocValuesField(fieldName, encodedRange)));
+        }, hdr -> {}, fieldType, fieldName));
     }
 
     public void testNoMatchingField() throws IOException {
diff --git a/server/src/test/java/org/opensearch/search/aggregations/metrics/InternalScriptedMetricTests.java b/server/src/test/java/org/opensearch/search/aggregations/metrics/InternalScriptedMetricTests.java
index 69c53d1a526e8..1a10a2fa35f84 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/metrics/InternalScriptedMetricTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/metrics/InternalScriptedMetricTests.java
@@ -279,12 +279,7 @@ protected InternalScriptedMetric mutateInstance(InternalScriptedMetric instance)
 
     public void testOldSerialization() throws IOException {
         // A single element list looks like a fully reduced agg
-        InternalScriptedMetric original = new InternalScriptedMetric(
-            "test",
-            org.opensearch.common.collect.List.of("foo"),
-            new Script("test"),
-            null
-        );
+        InternalScriptedMetric original = new InternalScriptedMetric("test", List.of("foo"), new Script("test"), null);
         original.mergePipelineTreeForBWCSerialization(PipelineTree.EMPTY);
         InternalScriptedMetric roundTripped = (InternalScriptedMetric) copyNamedWriteable(
             original,
@@ -295,12 +290,7 @@ public void testOldSerialization() throws IOException {
         assertThat(roundTripped, equalTo(original));
 
         // A multi-element list looks like a non-reduced agg
-        InternalScriptedMetric unreduced = new InternalScriptedMetric(
-            "test",
-            org.opensearch.common.collect.List.of("foo", "bar"),
-            new Script("test"),
-            null
-        );
+        InternalScriptedMetric unreduced = new InternalScriptedMetric("test", List.of("foo", "bar"), new Script("test"), null);
         unreduced.mergePipelineTreeForBWCSerialization(PipelineTree.EMPTY);
         Exception e = expectThrows(
             IllegalArgumentException.class,
diff --git a/server/src/test/java/org/opensearch/search/aggregations/metrics/MinAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/metrics/MinAggregatorTests.java
index 05b3c5c7e57db..f0273b46ef97e 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/metrics/MinAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/metrics/MinAggregatorTests.java
@@ -302,13 +302,9 @@ public void testUnsupportedType() {
 
         IllegalArgumentException e = expectThrows(
             IllegalArgumentException.class,
-            () -> testCase(
-                aggregationBuilder,
-                new MatchAllDocsQuery(),
-                iw -> { iw.addDocument(singleton(new SortedSetDocValuesField("string", new BytesRef("foo")))); },
-                (Consumer<InternalMin>) min -> { fail("Should have thrown exception"); },
-                fieldType
-            )
+            () -> testCase(aggregationBuilder, new MatchAllDocsQuery(), iw -> {
+                iw.addDocument(singleton(new SortedSetDocValuesField("string", new BytesRef("foo"))));
+            }, (Consumer<InternalMin>) min -> { fail("Should have thrown exception"); }, fieldType)
         );
         assertEquals("Field [not_a_number] of type [keyword] is not supported for aggregation [min]", e.getMessage());
     }
diff --git a/server/src/test/java/org/opensearch/search/aggregations/metrics/ScriptedMetricAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/metrics/ScriptedMetricAggregatorTests.java
index f2a61521eff1f..6a4ecf01577d8 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/metrics/ScriptedMetricAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/metrics/ScriptedMetricAggregatorTests.java
@@ -593,12 +593,9 @@ public void testInitScriptMakesArray() throws IOException {
             .mapScript(MAP_SCRIPT)
             .combineScript(COMBINE_SCRIPT)
             .reduceScript(REDUCE_SCRIPT);
-        testCase(
-            aggregationBuilder,
-            new MatchAllDocsQuery(),
-            iw -> { iw.addDocument(new Document()); },
-            (InternalScriptedMetric r) -> { assertEquals(1, r.aggregation()); }
-        );
+        testCase(aggregationBuilder, new MatchAllDocsQuery(), iw -> { iw.addDocument(new Document()); }, (InternalScriptedMetric r) -> {
+            assertEquals(1, r.aggregation());
+        });
     }
 
     public void testAsSubAgg() throws IOException {
diff --git a/server/src/test/java/org/opensearch/search/aggregations/metrics/StatsAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/metrics/StatsAggregatorTests.java
index d8d736595164a..c215c0959b342 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/metrics/StatsAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/metrics/StatsAggregatorTests.java
@@ -470,7 +470,7 @@ protected AggregationBuilder createAggBuilderForTypeTest(MappedFieldType fieldTy
 
     @Override
     protected ScriptService getMockScriptService() {
-        final Map<String, Function<Map<String, Object>, Object>> scripts = org.opensearch.common.collect.Map.of(
+        final Map<String, Function<Map<String, Object>, Object>> scripts = Map.of(
             VALUE_SCRIPT_NAME,
             vars -> ((Number) vars.get("_value")).doubleValue() + 1,
             FIELD_SCRIPT_NAME,
diff --git a/server/src/test/java/org/opensearch/search/aggregations/metrics/SumAggregatorTests.java b/server/src/test/java/org/opensearch/search/aggregations/metrics/SumAggregatorTests.java
index 8c0087ca0b87d..72b09d7509b02 100644
--- a/server/src/test/java/org/opensearch/search/aggregations/metrics/SumAggregatorTests.java
+++ b/server/src/test/java/org/opensearch/search/aggregations/metrics/SumAggregatorTests.java
@@ -418,7 +418,7 @@ protected AggregationBuilder createAggBuilderForTypeTest(MappedFieldType fieldTy
 
     @Override
     protected ScriptService getMockScriptService() {
-        final Map<String, Function<Map<String, Object>, Object>> scripts = org.opensearch.common.collect.Map.of(
+        final Map<String, Function<Map<String, Object>, Object>> scripts = Map.of(
             VALUE_SCRIPT_NAME,
             vars -> ((Number) vars.get("_value")).doubleValue() + 1,
             FIELD_SCRIPT_NAME,
diff --git a/server/src/test/java/org/opensearch/search/fetch/subphase/FieldFetcherTests.java b/server/src/test/java/org/opensearch/search/fetch/subphase/FieldFetcherTests.java
index 0aff1efff88ef..153ce14c0e385 100644
--- a/server/src/test/java/org/opensearch/search/fetch/subphase/FieldFetcherTests.java
+++ b/server/src/test/java/org/opensearch/search/fetch/subphase/FieldFetcherTests.java
@@ -49,6 +49,7 @@
 import java.io.IOException;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 import static org.hamcrest.Matchers.containsInAnyOrder;
 import static org.hamcrest.Matchers.equalTo;
@@ -66,10 +67,7 @@ public void testLeafValues() throws IOException {
             .endObject()
             .endObject();
 
-        List<FieldAndFormat> fieldAndFormats = org.opensearch.common.collect.List.of(
-            new FieldAndFormat("field", null),
-            new FieldAndFormat("object.field", null)
-        );
+        List<FieldAndFormat> fieldAndFormats = List.of(new FieldAndFormat("field", null), new FieldAndFormat("object.field", null));
         Map<String, DocumentField> fields = fetchFields(mapperService, source, fieldAndFormats);
         assertThat(fields.size(), equalTo(2));
 
@@ -100,7 +98,7 @@ public void testObjectValues() throws IOException {
         DocumentField rangeField = fields.get("float_range");
         assertNotNull(rangeField);
         assertThat(rangeField.getValues().size(), equalTo(1));
-        assertThat(rangeField.getValue(), equalTo(org.opensearch.common.collect.Map.of("gte", 0.0f, "lte", 2.718f)));
+        assertThat(rangeField.getValue(), equalTo(Map.of("gte", 0.0f, "lte", 2.718f)));
     }
 
     public void testNonExistentField() throws IOException {
@@ -255,7 +253,7 @@ public void testDateFormat() throws IOException {
         Map<String, DocumentField> fields = fetchFields(
             mapperService,
             source,
-            org.opensearch.common.collect.List.of(new FieldAndFormat("field", null), new FieldAndFormat("date_field", "yyyy/MM/dd"))
+            List.of(new FieldAndFormat("field", null), new FieldAndFormat("date_field", "yyyy/MM/dd"))
         );
         assertThat(fields.size(), equalTo(2));
 
@@ -440,7 +438,7 @@ public void testTextSubFields() throws IOException {
     private static Map<String, DocumentField> fetchFields(MapperService mapperService, XContentBuilder source, String fieldPattern)
         throws IOException {
 
-        List<FieldAndFormat> fields = org.opensearch.common.collect.List.of(new FieldAndFormat(fieldPattern, null));
+        List<FieldAndFormat> fields = List.of(new FieldAndFormat(fieldPattern, null));
         return fetchFields(mapperService, source, fields);
     }
 
@@ -451,7 +449,7 @@ private static Map<String, DocumentField> fetchFields(MapperService mapperServic
         sourceLookup.setSource(BytesReference.bytes(source));
 
         FieldFetcher fieldFetcher = FieldFetcher.create(createQueryShardContext(mapperService), null, fields);
-        return fieldFetcher.fetch(sourceLookup, org.opensearch.common.collect.Set.of());
+        return fieldFetcher.fetch(sourceLookup, Set.of());
     }
 
     public MapperService createMapperService() throws IOException {
diff --git a/server/src/test/java/org/opensearch/search/fetch/subphase/highlight/HighlightFieldTests.java b/server/src/test/java/org/opensearch/search/fetch/subphase/highlight/HighlightFieldTests.java
index 6fb53c2ed1da0..d3d7c1aa8d411 100644
--- a/server/src/test/java/org/opensearch/search/fetch/subphase/highlight/HighlightFieldTests.java
+++ b/server/src/test/java/org/opensearch/search/fetch/subphase/highlight/HighlightFieldTests.java
@@ -53,19 +53,32 @@ public class HighlightFieldTests extends OpenSearchTestCase {
 
     public static HighlightField createTestItem() {
         String name = frequently() ? randomAlphaOfLengthBetween(5, 20) : randomRealisticUnicodeOfCodepointLengthBetween(5, 20);
+        name = replaceUnicodeControlCharacters(name);
         Text[] fragments = null;
         if (frequently()) {
             int size = randomIntBetween(0, 5);
             fragments = new Text[size];
             for (int i = 0; i < size; i++) {
-                fragments[i] = new Text(
-                    frequently() ? randomAlphaOfLengthBetween(10, 30) : randomRealisticUnicodeOfCodepointLengthBetween(10, 30)
-                );
+                String fragmentText = frequently()
+                    ? randomAlphaOfLengthBetween(10, 30)
+                    : randomRealisticUnicodeOfCodepointLengthBetween(10, 30);
+                fragmentText = replaceUnicodeControlCharacters(fragmentText);
+                fragments[i] = new Text(fragmentText);
             }
         }
         return new HighlightField(name, fragments);
     }
 
+    public void testReplaceUnicodeControlCharacters() {
+        assertEquals("æÆ ¢¡Èýñ«Ò", replaceUnicodeControlCharacters("æÆ\u0000¢¡Èýñ«Ò"));
+        assertEquals("test_string_without_control_characters", replaceUnicodeControlCharacters("test_string_without_control_characters"));
+        assertEquals("æÆ@¢¡Èýñ«Ò", replaceUnicodeControlCharacters("æÆ\u0000¢¡Èýñ«Ò", "@"));
+        assertEquals(
+            "test_string_without_control_characters",
+            replaceUnicodeControlCharacters("test_string_without_control_characters", "@")
+        );
+    }
+
     public void testFromXContent() throws IOException {
         HighlightField highlightField = createTestItem();
         XContentType xcontentType = randomFrom(XContentType.values());
diff --git a/server/src/test/java/org/opensearch/search/profile/ProfileResultTests.java b/server/src/test/java/org/opensearch/search/profile/ProfileResultTests.java
index b24e8f31dd020..37d35586996d0 100644
--- a/server/src/test/java/org/opensearch/search/profile/ProfileResultTests.java
+++ b/server/src/test/java/org/opensearch/search/profile/ProfileResultTests.java
@@ -121,26 +121,8 @@ private void doFromXContentTestWithRandomFields(boolean addRandomFields) throws
 
     public void testToXContent() throws IOException {
         List<ProfileResult> children = new ArrayList<>();
-        children.add(
-            new ProfileResult(
-                "child1",
-                "desc1",
-                org.opensearch.common.collect.Map.of("key1", 100L),
-                org.opensearch.common.collect.Map.of(),
-                100L,
-                org.opensearch.common.collect.List.of()
-            )
-        );
-        children.add(
-            new ProfileResult(
-                "child2",
-                "desc2",
-                org.opensearch.common.collect.Map.of("key1", 123356L),
-                org.opensearch.common.collect.Map.of(),
-                123356L,
-                org.opensearch.common.collect.List.of()
-            )
-        );
+        children.add(new ProfileResult("child1", "desc1", Map.of("key1", 100L), Map.of(), 100L, List.of()));
+        children.add(new ProfileResult("child2", "desc2", Map.of("key1", 123356L), Map.of(), 123356L, List.of()));
         Map<String, Long> breakdown = new LinkedHashMap<>();
         breakdown.put("key1", 123456L);
         breakdown.put("stuff", 10000L);
@@ -225,14 +207,7 @@ public void testToXContent() throws IOException {
             Strings.toString(builder)
         );
 
-        result = new ProfileResult(
-            "profileName",
-            "some description",
-            org.opensearch.common.collect.Map.of("key1", 12345678L),
-            org.opensearch.common.collect.Map.of(),
-            12345678L,
-            org.opensearch.common.collect.List.of()
-        );
+        result = new ProfileResult("profileName", "some description", Map.of("key1", 12345678L), Map.of(), 12345678L, List.of());
         builder = XContentFactory.jsonBuilder().prettyPrint().humanReadable(true);
         result.toXContent(builder, ToXContent.EMPTY_PARAMS);
         assertEquals(
@@ -248,14 +223,7 @@ public void testToXContent() throws IOException {
             Strings.toString(builder)
         );
 
-        result = new ProfileResult(
-            "profileName",
-            "some description",
-            org.opensearch.common.collect.Map.of("key1", 1234567890L),
-            org.opensearch.common.collect.Map.of(),
-            1234567890L,
-            org.opensearch.common.collect.List.of()
-        );
+        result = new ProfileResult("profileName", "some description", Map.of("key1", 1234567890L), Map.of(), 1234567890L, List.of());
         builder = XContentFactory.jsonBuilder().prettyPrint().humanReadable(true);
         result.toXContent(builder, ToXContent.EMPTY_PARAMS);
         assertEquals(
diff --git a/server/src/test/java/org/opensearch/search/profile/aggregation/AggregationProfileShardResultTests.java b/server/src/test/java/org/opensearch/search/profile/aggregation/AggregationProfileShardResultTests.java
index 2827bcd098bcc..3c1f2e08cf3db 100644
--- a/server/src/test/java/org/opensearch/search/profile/aggregation/AggregationProfileShardResultTests.java
+++ b/server/src/test/java/org/opensearch/search/profile/aggregation/AggregationProfileShardResultTests.java
@@ -87,7 +87,7 @@ public void testToXContent() throws IOException {
         breakdown.put("timing2", 4000L);
         Map<String, Object> debug = new LinkedHashMap<>();
         debug.put("stuff", "stuff");
-        debug.put("other_stuff", org.opensearch.common.collect.List.of("foo", "bar"));
+        debug.put("other_stuff", List.of("foo", "bar"));
         ProfileResult profileResult = new ProfileResult("someType", "someDescription", breakdown, debug, 6000L, Collections.emptyList());
         profileResults.add(profileResult);
         AggregationProfileShardResult aggProfileResults = new AggregationProfileShardResult(profileResults);
diff --git a/server/src/test/java/org/opensearch/search/suggest/SuggestBuilderTests.java b/server/src/test/java/org/opensearch/search/suggest/SuggestBuilderTests.java
index 709cf0c6a763f..e34c48d59ef6e 100644
--- a/server/src/test/java/org/opensearch/search/suggest/SuggestBuilderTests.java
+++ b/server/src/test/java/org/opensearch/search/suggest/SuggestBuilderTests.java
@@ -102,11 +102,9 @@ public void testFromXContent() throws IOException {
     public void testEqualsAndHashcode() throws IOException {
         for (int runs = 0; runs < NUMBER_OF_RUNS; runs++) {
             // explicit about type parameters, see: https://bugs.eclipse.org/bugs/show_bug.cgi?id=481649
-            EqualsHashCodeTestUtils.<SuggestBuilder>checkEqualsAndHashCode(
-                randomSuggestBuilder(),
-                original -> { return copyWriteable(original, namedWriteableRegistry, SuggestBuilder::new); },
-                this::createMutation
-            );
+            EqualsHashCodeTestUtils.<SuggestBuilder>checkEqualsAndHashCode(randomSuggestBuilder(), original -> {
+                return copyWriteable(original, namedWriteableRegistry, SuggestBuilder::new);
+            }, this::createMutation);
         }
     }
 
diff --git a/server/src/test/java/org/opensearch/snapshots/SnapshotResiliencyTests.java b/server/src/test/java/org/opensearch/snapshots/SnapshotResiliencyTests.java
index a6677fbc0c99b..b9087db60c271 100644
--- a/server/src/test/java/org/opensearch/snapshots/SnapshotResiliencyTests.java
+++ b/server/src/test/java/org/opensearch/snapshots/SnapshotResiliencyTests.java
@@ -169,6 +169,7 @@
 import org.opensearch.gateway.TransportNodesListGatewayStartedShards;
 import org.opensearch.index.Index;
 import org.opensearch.index.IndexingPressureService;
+import org.opensearch.index.SegmentReplicationPressureService;
 import org.opensearch.index.analysis.AnalysisRegistry;
 import org.opensearch.index.seqno.GlobalCheckpointSyncAction;
 import org.opensearch.index.seqno.RetentionLeaseSyncer;
@@ -1978,6 +1979,7 @@ public void onFailure(final Exception e) {
                     new UpdateHelper(scriptService),
                     actionFilters,
                     new IndexingPressureService(settings, clusterService),
+                    new SegmentReplicationPressureService(settings, clusterService, mock(IndicesService.class)),
                     new SystemIndices(emptyMap())
                 );
                 actions.put(
diff --git a/server/src/test/java/org/opensearch/transport/InboundHandlerTests.java b/server/src/test/java/org/opensearch/transport/InboundHandlerTests.java
index 4076e7229ebf7..c340042f99d86 100644
--- a/server/src/test/java/org/opensearch/transport/InboundHandlerTests.java
+++ b/server/src/test/java/org/opensearch/transport/InboundHandlerTests.java
@@ -63,6 +63,8 @@
 import java.io.InputStream;
 import java.nio.ByteBuffer;
 import java.util.Collections;
+import java.util.Map;
+import java.util.Set;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicReference;
@@ -254,8 +256,8 @@ public void testSendsErrorResponseToHandshakeFromCompatibleVersion() throws Exce
         );
         final InboundMessage requestMessage = unreadableInboundHandshake(remoteVersion, requestHeader);
         requestHeader.actionName = TransportHandshaker.HANDSHAKE_ACTION_NAME;
-        requestHeader.headers = Tuple.tuple(org.opensearch.common.collect.Map.of(), org.opensearch.common.collect.Map.of());
-        requestHeader.features = org.opensearch.common.collect.Set.of();
+        requestHeader.headers = Tuple.tuple(Map.of(), Map.of());
+        requestHeader.features = Set.of();
         handler.inboundMessage(channel, requestMessage);
 
         final BytesReference responseBytesReference = channel.getMessageCaptor().get();
@@ -294,8 +296,8 @@ public void testClosesChannelOnErrorInHandshakeWithIncompatibleVersion() throws
             );
             final InboundMessage requestMessage = unreadableInboundHandshake(remoteVersion, requestHeader);
             requestHeader.actionName = TransportHandshaker.HANDSHAKE_ACTION_NAME;
-            requestHeader.headers = Tuple.tuple(org.opensearch.common.collect.Map.of(), org.opensearch.common.collect.Map.of());
-            requestHeader.features = org.opensearch.common.collect.Set.of();
+            requestHeader.headers = Tuple.tuple(Map.of(), Map.of());
+            requestHeader.features = Set.of();
             handler.inboundMessage(channel, requestMessage);
             assertTrue(isClosed.get());
             assertNull(channel.getMessageCaptor().get());
@@ -332,7 +334,7 @@ public void testLogsSlowInboundProcessing() throws Exception {
             });
             requestHeader.actionName = TransportHandshaker.HANDSHAKE_ACTION_NAME;
             requestHeader.headers = Tuple.tuple(Collections.emptyMap(), Collections.emptyMap());
-            requestHeader.features = org.opensearch.common.collect.Set.of();
+            requestHeader.features = Set.of();
             handler.inboundMessage(channel, requestMessage);
             assertNotNull(channel.getMessageCaptor().get());
             mockAppender.assertAllExpectationsMatched();
diff --git a/server/src/test/java/org/opensearch/transport/TransportActionProxyTests.java b/server/src/test/java/org/opensearch/transport/TransportActionProxyTests.java
index 33f5a8d9e852f..0488f249cb09e 100644
--- a/server/src/test/java/org/opensearch/transport/TransportActionProxyTests.java
+++ b/server/src/test/java/org/opensearch/transport/TransportActionProxyTests.java
@@ -168,12 +168,9 @@ public void testException() throws InterruptedException {
         });
         TransportActionProxy.registerProxyAction(serviceB, "internal:test", SimpleTestResponse::new);
         serviceB.connectToNode(nodeC);
-        serviceC.registerRequestHandler(
-            "internal:test",
-            ThreadPool.Names.SAME,
-            SimpleTestRequest::new,
-            (request, channel, task) -> { throw new OpenSearchException("greetings from TS_C"); }
-        );
+        serviceC.registerRequestHandler("internal:test", ThreadPool.Names.SAME, SimpleTestRequest::new, (request, channel, task) -> {
+            throw new OpenSearchException("greetings from TS_C");
+        });
         TransportActionProxy.registerProxyAction(serviceC, "internal:test", SimpleTestResponse::new);
 
         CountDownLatch latch = new CountDownLatch(1);
diff --git a/server/src/test/java/org/opensearch/transport/TransportServiceHandshakeTests.java b/server/src/test/java/org/opensearch/transport/TransportServiceHandshakeTests.java
index c0af5d6e76c59..357d7fffa8df6 100644
--- a/server/src/test/java/org/opensearch/transport/TransportServiceHandshakeTests.java
+++ b/server/src/test/java/org/opensearch/transport/TransportServiceHandshakeTests.java
@@ -218,10 +218,9 @@ public void testNodeConnectWithDifferentNodeId() {
             emptySet(),
             handleB.discoveryNode.getVersion()
         );
-        ConnectTransportException ex = expectThrows(
-            ConnectTransportException.class,
-            () -> { handleA.transportService.connectToNode(discoveryNode, TestProfiles.LIGHT_PROFILE); }
-        );
+        ConnectTransportException ex = expectThrows(ConnectTransportException.class, () -> {
+            handleA.transportService.connectToNode(discoveryNode, TestProfiles.LIGHT_PROFILE);
+        });
         assertThat(ex.getMessage(), containsString("unexpected remote node"));
         assertFalse(handleA.transportService.nodeConnected(discoveryNode));
     }
diff --git a/server/src/test/resources/org/opensearch/index/analysis/shingle_analysis.json b/server/src/test/resources/org/opensearch/index/analysis/shingle_analysis.json
index 53e5bbd9fa946..4a4fc7d2c81b1 100644
--- a/server/src/test/resources/org/opensearch/index/analysis/shingle_analysis.json
+++ b/server/src/test/resources/org/opensearch/index/analysis/shingle_analysis.json
@@ -17,7 +17,7 @@
                     "output_unigrams" : false,
                     "filler_token" : "FILLER"
                 }
-            }            
+            }
         }
     }
-}
+}
\ No newline at end of file
diff --git a/server/src/test/resources/org/opensearch/index/analysis/shingle_analysis2.json b/server/src/test/resources/org/opensearch/index/analysis/shingle_analysis2.json
index 19b4d24063b8e..5927549c111fd 100644
--- a/server/src/test/resources/org/opensearch/index/analysis/shingle_analysis2.json
+++ b/server/src/test/resources/org/opensearch/index/analysis/shingle_analysis2.json
@@ -9,7 +9,7 @@
                     "output_unigrams" : false,
                     "filler_token" : "FILLER"
                 }
-            }            
+            }
         }
     }
 }
diff --git a/test/fixtures/hdfs-fixture/build.gradle b/test/fixtures/hdfs-fixture/build.gradle
index b8b5406bd39f3..43f3838999080 100644
--- a/test/fixtures/hdfs-fixture/build.gradle
+++ b/test/fixtures/hdfs-fixture/build.gradle
@@ -50,12 +50,12 @@ dependencies {
   api "com.fasterxml.jackson.jaxrs:jackson-jaxrs-json-provider:${versions.jackson}"
   api "com.fasterxml.jackson.core:jackson-databind:${versions.jackson_databind}"
   api "com.fasterxml.woodstox:woodstox-core:${versions.woodstox}"
-  api 'net.minidev:json-smart:2.4.8'
+  api 'net.minidev:json-smart:2.4.9'
   api "org.mockito:mockito-core:${versions.mockito}"
   api "com.google.protobuf:protobuf-java:3.21.9"
   api "org.jetbrains.kotlin:kotlin-stdlib:${versions.kotlin}"
   api 'org.eclipse.jetty:jetty-server:9.4.49.v20220914'
-  api 'org.apache.zookeeper:zookeeper:3.8.0'
+  api 'org.apache.zookeeper:zookeeper:3.8.1'
   api "org.apache.commons:commons-text:1.10.0"
   api "commons-net:commons-net:3.9.0"
   runtimeOnly "com.google.guava:guava:${versions.guava}"
diff --git a/test/framework/build.gradle b/test/framework/build.gradle
index 00d907ce6d108..255f554db7a79 100644
--- a/test/framework/build.gradle
+++ b/test/framework/build.gradle
@@ -88,7 +88,7 @@ test {
   systemProperty 'tests.gradle_index_compat_versions', BuildParams.bwcVersions.indexCompatible.join(',')
   systemProperty 'tests.gradle_wire_compat_versions', BuildParams.bwcVersions.wireCompatible.join(',')
   systemProperty 'tests.gradle_unreleased_versions', BuildParams.bwcVersions.unreleased.join(',')
-  
+
   if (BuildParams.runtimeJavaVersion >= JavaVersion.VERSION_18) {
     jvmArgs += ["-Djava.security.manager=allow"]
   }
diff --git a/test/framework/src/main/java/org/opensearch/cluster/OpenSearchAllocationTestCase.java b/test/framework/src/main/java/org/opensearch/cluster/OpenSearchAllocationTestCase.java
index 1d527140dc038..ff0ad0c69e4e5 100644
--- a/test/framework/src/main/java/org/opensearch/cluster/OpenSearchAllocationTestCase.java
+++ b/test/framework/src/main/java/org/opensearch/cluster/OpenSearchAllocationTestCase.java
@@ -60,11 +60,14 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
+import java.util.Formatter;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Random;
 import java.util.Set;
+import java.util.TreeMap;
 
 import static java.util.Collections.emptyMap;
 import static org.opensearch.cluster.routing.ShardRoutingState.INITIALIZING;
@@ -306,6 +309,101 @@ public Decision canAllocate(ShardRouting shardRouting, RoutingAllocation allocat
         }
     }
 
+    /**
+     * Utility class to show shards distribution across nodes.
+     */
+    public static class ShardAllocations {
+
+        private static final String separator = "===================================================";
+        private static final String ONE_LINE_RETURN = "\n";
+        private static final String TWO_LINE_RETURN = "\n\n";
+
+        /**
+         Store shard primary/replica shard count against a node.
+         String: NodeId
+         int[]: tuple storing primary shard count in 0th index and replica's in 1st
+         */
+        static TreeMap<String, int[]> nodeToShardCountMap = new TreeMap<>();
+
+        /**
+         * Helper map containing NodeName to NodeId
+         */
+        static TreeMap<String, String> nameToNodeId = new TreeMap<>();
+
+        /*
+        Unassigned array containing primary at 0, replica at 1
+         */
+        static int[] unassigned = new int[2];
+
+        static int[] totalShards = new int[2];
+
+        private final static String printShardAllocationWithHeader(int[] shardCount) {
+            StringBuffer sb = new StringBuffer();
+            Formatter formatter = new Formatter(sb, Locale.getDefault());
+            formatter.format("%-20s %-20s\n", "P", shardCount[0]);
+            formatter.format("%-20s %-20s\n", "R", shardCount[1]);
+            return sb.toString();
+        }
+
+        private static void reset() {
+            nodeToShardCountMap.clear();
+            nameToNodeId.clear();
+            totalShards[0] = totalShards[1] = 0;
+            unassigned[0] = unassigned[1] = 0;
+        }
+
+        private static void buildMap(ClusterState inputState) {
+            reset();
+            for (RoutingNode node : inputState.getRoutingNodes()) {
+                if (node.node().getName() != null && node.node().getName().isEmpty() == false) {
+                    nameToNodeId.putIfAbsent(node.node().getName(), node.nodeId());
+                } else {
+                    nameToNodeId.putIfAbsent(node.nodeId(), node.nodeId());
+                }
+                nodeToShardCountMap.putIfAbsent(node.nodeId(), new int[] { 0, 0 });
+            }
+            for (ShardRouting shardRouting : inputState.routingTable().allShards()) {
+                // Fetch shard to update. Initialize local array
+                updateMap(nodeToShardCountMap, shardRouting);
+            }
+        }
+
+        private static void updateMap(TreeMap<String, int[]> mapToUpdate, ShardRouting shardRouting) {
+            int[] shard;
+            shard = shardRouting.assignedToNode() ? mapToUpdate.get(shardRouting.currentNodeId()) : unassigned;
+            // Update shard type count
+            if (shardRouting.primary()) {
+                shard[0]++;
+                totalShards[0]++;
+            } else {
+                shard[1]++;
+                totalShards[1]++;
+            }
+            // For assigned shards, put back counter
+            if (shardRouting.assignedToNode()) mapToUpdate.put(shardRouting.currentNodeId(), shard);
+        }
+
+        private static String allocation() {
+            StringBuffer sb = new StringBuffer();
+            sb.append(TWO_LINE_RETURN + separator + ONE_LINE_RETURN);
+            Formatter formatter = new Formatter(sb, Locale.getDefault());
+            for (Map.Entry<String, String> entry : nameToNodeId.entrySet()) {
+                String nodeId = nameToNodeId.get(entry.getKey());
+                formatter.format("%-20s\n", entry.getKey().toUpperCase(Locale.getDefault()));
+                sb.append(printShardAllocationWithHeader(nodeToShardCountMap.get(nodeId)));
+            }
+            sb.append(ONE_LINE_RETURN);
+            formatter.format("%-20s (P)%-5s (R)%-5s\n\n", "Unassigned ", unassigned[0], unassigned[1]);
+            formatter.format("%-20s (P)%-5s (R)%-5s\n\n", "Total Shards", totalShards[0], totalShards[1]);
+            return sb.toString();
+        }
+
+        public static String printShardDistribution(ClusterState state) {
+            buildMap(state);
+            return allocation();
+        }
+    }
+
     /** A lock {@link AllocationService} allowing tests to override time */
     protected static class MockAllocationService extends AllocationService {
 
diff --git a/test/framework/src/main/java/org/opensearch/cluster/routing/TestShardRouting.java b/test/framework/src/main/java/org/opensearch/cluster/routing/TestShardRouting.java
index 29207cbc4ada1..76325b6a0035b 100644
--- a/test/framework/src/main/java/org/opensearch/cluster/routing/TestShardRouting.java
+++ b/test/framework/src/main/java/org/opensearch/cluster/routing/TestShardRouting.java
@@ -205,6 +205,28 @@ public static ShardRouting newShardRouting(
         );
     }
 
+    public static ShardRouting newShardRouting(
+        ShardId shardId,
+        String currentNodeId,
+        String relocatingNodeId,
+        boolean primary,
+        ShardRoutingState state,
+        RecoverySource recoverySource,
+        UnassignedInfo unassignedInfo
+    ) {
+        return new ShardRouting(
+            shardId,
+            currentNodeId,
+            relocatingNodeId,
+            primary,
+            state,
+            recoverySource,
+            unassignedInfo,
+            buildAllocationId(state),
+            -1
+        );
+    }
+
     public static ShardRouting relocate(ShardRouting shardRouting, String relocatingNodeId, long expectedShardSize) {
         return shardRouting.relocate(relocatingNodeId, expectedShardSize);
     }
diff --git a/test/framework/src/main/java/org/opensearch/index/mapper/FieldTypeTestCase.java b/test/framework/src/main/java/org/opensearch/index/mapper/FieldTypeTestCase.java
index 571f1b21dd7e3..7ed0da8509fab 100644
--- a/test/framework/src/main/java/org/opensearch/index/mapper/FieldTypeTestCase.java
+++ b/test/framework/src/main/java/org/opensearch/index/mapper/FieldTypeTestCase.java
@@ -38,6 +38,7 @@
 import java.io.IOException;
 import java.util.Collections;
 import java.util.List;
+import java.util.Set;
 
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
@@ -65,7 +66,7 @@ public static List<?> fetchSourceValue(MappedFieldType fieldType, Object sourceV
     public static List<?> fetchSourceValue(MappedFieldType fieldType, Object sourceValue, String format) throws IOException {
         String field = fieldType.name();
         QueryShardContext context = mock(QueryShardContext.class);
-        when(context.sourcePath(field)).thenReturn(org.opensearch.common.collect.Set.of(field));
+        when(context.sourcePath(field)).thenReturn(Set.of(field));
 
         ValueFetcher fetcher = fieldType.valueFetcher(context, null, format);
         SourceLookup lookup = new SourceLookup();
diff --git a/test/framework/src/main/java/org/opensearch/index/mapper/MapperServiceTestCase.java b/test/framework/src/main/java/org/opensearch/index/mapper/MapperServiceTestCase.java
index db6c53bd0aa77..4b3405e925fd6 100644
--- a/test/framework/src/main/java/org/opensearch/index/mapper/MapperServiceTestCase.java
+++ b/test/framework/src/main/java/org/opensearch/index/mapper/MapperServiceTestCase.java
@@ -155,7 +155,9 @@ protected final MapperService createMapperService(Version version, XContentBuild
             xContentRegistry(),
             similarityService,
             mapperRegistry,
-            () -> { throw new UnsupportedOperationException(); },
+            () -> {
+                throw new UnsupportedOperationException();
+            },
             () -> true,
             scriptService
         );
@@ -249,9 +251,9 @@ QueryShardContext createQueryShardContext(MapperService mapperService) {
             inv -> mapperService.simpleMatchToFullName(inv.getArguments()[0].toString())
         );
         when(queryShardContext.allowExpensiveQueries()).thenReturn(true);
-        when(queryShardContext.lookup()).thenReturn(
-            new SearchLookup(mapperService, (ft, s) -> { throw new UnsupportedOperationException("search lookup not available"); })
-        );
+        when(queryShardContext.lookup()).thenReturn(new SearchLookup(mapperService, (ft, s) -> {
+            throw new UnsupportedOperationException("search lookup not available");
+        }));
         return queryShardContext;
     }
 }
diff --git a/test/framework/src/main/java/org/opensearch/index/mapper/MapperTestCase.java b/test/framework/src/main/java/org/opensearch/index/mapper/MapperTestCase.java
index c00a3831c0d8d..151170cd03aff 100644
--- a/test/framework/src/main/java/org/opensearch/index/mapper/MapperTestCase.java
+++ b/test/framework/src/main/java/org/opensearch/index/mapper/MapperTestCase.java
@@ -286,22 +286,22 @@ protected final List<?> fetchFromDocValues(MapperService mapperService, MappedFi
         throws IOException {
 
         BiFunction<MappedFieldType, Supplier<SearchLookup>, IndexFieldData<?>> fieldDataLookup = (mft, lookupSource) -> mft
-            .fielddataBuilder("test", () -> { throw new UnsupportedOperationException(); })
+            .fielddataBuilder("test", () -> {
+                throw new UnsupportedOperationException();
+            })
             .build(new IndexFieldDataCache.None(), new NoneCircuitBreakerService());
         SetOnce<List<?>> result = new SetOnce<>();
-        withLuceneIndex(
-            mapperService,
-            iw -> { iw.addDocument(mapperService.documentMapper().parse(source(b -> b.field(ft.name(), sourceValue))).rootDoc()); },
-            iw -> {
-                SearchLookup lookup = new SearchLookup(mapperService, fieldDataLookup);
-                ValueFetcher valueFetcher = new DocValueFetcher(format, lookup.doc().getForField(ft));
-                IndexSearcher searcher = newSearcher(iw);
-                LeafReaderContext context = searcher.getIndexReader().leaves().get(0);
-                lookup.source().setSegmentAndDocument(context, 0);
-                valueFetcher.setNextReader(context);
-                result.set(valueFetcher.fetchValues(lookup.source()));
-            }
-        );
+        withLuceneIndex(mapperService, iw -> {
+            iw.addDocument(mapperService.documentMapper().parse(source(b -> b.field(ft.name(), sourceValue))).rootDoc());
+        }, iw -> {
+            SearchLookup lookup = new SearchLookup(mapperService, fieldDataLookup);
+            ValueFetcher valueFetcher = new DocValueFetcher(format, lookup.doc().getForField(ft));
+            IndexSearcher searcher = newSearcher(iw);
+            LeafReaderContext context = searcher.getIndexReader().leaves().get(0);
+            lookup.source().setSegmentAndDocument(context, 0);
+            valueFetcher.setNextReader(context);
+            result.set(valueFetcher.fetchValues(lookup.source()));
+        });
         return result.get();
     }
 
diff --git a/test/framework/src/main/java/org/opensearch/index/replication/OpenSearchIndexLevelReplicationTestCase.java b/test/framework/src/main/java/org/opensearch/index/replication/OpenSearchIndexLevelReplicationTestCase.java
index 8df57ccad85cc..e349fbdd6f1fc 100644
--- a/test/framework/src/main/java/org/opensearch/index/replication/OpenSearchIndexLevelReplicationTestCase.java
+++ b/test/framework/src/main/java/org/opensearch/index/replication/OpenSearchIndexLevelReplicationTestCase.java
@@ -237,7 +237,9 @@ protected class ReplicationGroup implements AutoCloseable, Iterable<IndexShard>
             (shardId, primaryAllocationId, primaryTerm, retentionLeases) -> syncRetentionLeases(
                 shardId,
                 retentionLeases,
-                ActionListener.wrap(r -> {}, e -> { throw new AssertionError("failed to background sync retention lease", e); })
+                ActionListener.wrap(r -> {}, e -> {
+                    throw new AssertionError("failed to background sync retention lease", e);
+                })
             )
         );
 
diff --git a/test/framework/src/main/java/org/opensearch/index/seqno/RetentionLeaseUtils.java b/test/framework/src/main/java/org/opensearch/index/seqno/RetentionLeaseUtils.java
index bf06b481a2377..8216f1053a60b 100644
--- a/test/framework/src/main/java/org/opensearch/index/seqno/RetentionLeaseUtils.java
+++ b/test/framework/src/main/java/org/opensearch/index/seqno/RetentionLeaseUtils.java
@@ -53,13 +53,8 @@ public static Map<String, RetentionLease> toMapExcludingPeerRecoveryRetentionLea
         return retentionLeases.leases()
             .stream()
             .filter(l -> ReplicationTracker.PEER_RECOVERY_RETENTION_LEASE_SOURCE.equals(l.source()) == false)
-            .collect(
-                Collectors.toMap(
-                    RetentionLease::id,
-                    Function.identity(),
-                    (o1, o2) -> { throw new AssertionError("unexpectedly merging " + o1 + " and " + o2); },
-                    LinkedHashMap::new
-                )
-            );
+            .collect(Collectors.toMap(RetentionLease::id, Function.identity(), (o1, o2) -> {
+                throw new AssertionError("unexpectedly merging " + o1 + " and " + o2);
+            }, LinkedHashMap::new));
     }
 }
diff --git a/test/framework/src/main/java/org/opensearch/index/shard/IndexShardTestCase.java b/test/framework/src/main/java/org/opensearch/index/shard/IndexShardTestCase.java
index d39e190a6f124..ab0cf38f77c7d 100644
--- a/test/framework/src/main/java/org/opensearch/index/shard/IndexShardTestCase.java
+++ b/test/framework/src/main/java/org/opensearch/index/shard/IndexShardTestCase.java
@@ -1365,6 +1365,10 @@ public void onReplicationDone(SegmentReplicationState state) {
                             assertTrue(recoveryDiff.missing.isEmpty());
                             assertTrue(recoveryDiff.different.isEmpty());
                             assertEquals(recoveryDiff.identical.size(), primaryMetadata.size());
+                            primaryShard.updateVisibleCheckpointForShard(
+                                replica.routingEntry().allocationId().getId(),
+                                primaryShard.getLatestReplicationCheckpoint()
+                            );
                         } catch (Exception e) {
                             throw ExceptionsHelper.convertToRuntime(e);
                         } finally {
diff --git a/test/framework/src/main/java/org/opensearch/repositories/blobstore/OpenSearchMockAPIBasedRepositoryIntegTestCase.java b/test/framework/src/main/java/org/opensearch/repositories/blobstore/OpenSearchMockAPIBasedRepositoryIntegTestCase.java
index f082c7a45a207..85ff45b80fad6 100644
--- a/test/framework/src/main/java/org/opensearch/repositories/blobstore/OpenSearchMockAPIBasedRepositoryIntegTestCase.java
+++ b/test/framework/src/main/java/org/opensearch/repositories/blobstore/OpenSearchMockAPIBasedRepositoryIntegTestCase.java
@@ -358,7 +358,7 @@ public HttpHandler getDelegate() {
         }
 
         synchronized Map<String, Long> getOperationsCount() {
-            return org.opensearch.common.collect.Map.copyOf(operationCount);
+            return Map.copyOf(operationCount);
         }
 
         protected synchronized void trackRequest(final String requestType) {
diff --git a/test/framework/src/main/java/org/opensearch/script/MockScriptService.java b/test/framework/src/main/java/org/opensearch/script/MockScriptService.java
index e4887255d0b9f..4fbc4c4d4bc90 100644
--- a/test/framework/src/main/java/org/opensearch/script/MockScriptService.java
+++ b/test/framework/src/main/java/org/opensearch/script/MockScriptService.java
@@ -79,14 +79,10 @@ public <FactoryType> FactoryType compile(
 
             @Override
             public Set<ScriptContext<?>> getSupportedContexts() {
-                return org.opensearch.common.collect.Set.of(context);
+                return Set.of(context);
             }
         };
-        return new MockScriptService(
-            Settings.EMPTY,
-            org.opensearch.common.collect.Map.of("lang", engine),
-            org.opensearch.common.collect.Map.of(context.name, context)
-        ) {
+        return new MockScriptService(Settings.EMPTY, Map.of("lang", engine), Map.of(context.name, context)) {
             @Override
             protected StoredScriptSource getScriptFromClusterState(String id) {
                 return storedLookup.get(id);
diff --git a/test/framework/src/main/java/org/opensearch/test/AbstractBuilderTestCase.java b/test/framework/src/main/java/org/opensearch/test/AbstractBuilderTestCase.java
index fdf26608509f1..1b5abad719fbd 100644
--- a/test/framework/src/main/java/org/opensearch/test/AbstractBuilderTestCase.java
+++ b/test/framework/src/main/java/org/opensearch/test/AbstractBuilderTestCase.java
@@ -369,12 +369,9 @@ private static class ServiceHolder implements Closeable {
             boolean registerType
         ) throws IOException {
             this.nowInMillis = nowInMillis;
-            Environment env = InternalSettingsPreparer.prepareEnvironment(
-                nodeSettings,
-                emptyMap(),
-                null,
-                () -> { throw new AssertionError("node.name must be set"); }
-            );
+            Environment env = InternalSettingsPreparer.prepareEnvironment(nodeSettings, emptyMap(), null, () -> {
+                throw new AssertionError("node.name must be set");
+            });
             PluginsService pluginsService;
             pluginsService = new PluginsService(nodeSettings, null, env.modulesFile(), env.pluginsFile(), plugins);
 
diff --git a/test/framework/src/main/java/org/opensearch/test/AbstractQueryTestCase.java b/test/framework/src/main/java/org/opensearch/test/AbstractQueryTestCase.java
index ac493bdd68d71..c33fcb69eb9e2 100644
--- a/test/framework/src/main/java/org/opensearch/test/AbstractQueryTestCase.java
+++ b/test/framework/src/main/java/org/opensearch/test/AbstractQueryTestCase.java
@@ -732,7 +732,8 @@ protected static String getRandomRewriteMethod() {
                 .getPreferredName();
         } else {
             rewrite = randomFrom(QueryParsers.TOP_TERMS, QueryParsers.TOP_TERMS_BOOST, QueryParsers.TOP_TERMS_BLENDED_FREQS)
-                .getPreferredName() + "1";
+                .getPreferredName()
+                + "1";
         }
         return rewrite;
     }
diff --git a/test/framework/src/main/java/org/opensearch/test/InternalTestCluster.java b/test/framework/src/main/java/org/opensearch/test/InternalTestCluster.java
index 2de50fabbe396..240f6ef9c6e56 100644
--- a/test/framework/src/main/java/org/opensearch/test/InternalTestCluster.java
+++ b/test/framework/src/main/java/org/opensearch/test/InternalTestCluster.java
@@ -218,7 +218,7 @@ public final class InternalTestCluster extends TestCluster {
         nodeAndClient.node.settings()
     );
 
-    private static final ByteSizeValue DEFAULT_SEARCH_CACHE_SIZE = new ByteSizeValue(100, ByteSizeUnit.MB);
+    private static final ByteSizeValue DEFAULT_SEARCH_CACHE_SIZE = new ByteSizeValue(2, ByteSizeUnit.GB);
 
     public static final int DEFAULT_LOW_NUM_CLUSTER_MANAGER_NODES = 1;
     public static final int DEFAULT_HIGH_NUM_CLUSTER_MANAGER_NODES = 3;
diff --git a/test/framework/src/main/java/org/opensearch/test/OpenSearchTestCase.java b/test/framework/src/main/java/org/opensearch/test/OpenSearchTestCase.java
index d4090fdfdfdad..904f30a2edf95 100644
--- a/test/framework/src/main/java/org/opensearch/test/OpenSearchTestCase.java
+++ b/test/framework/src/main/java/org/opensearch/test/OpenSearchTestCase.java
@@ -883,6 +883,15 @@ public static String randomRealisticUnicodeOfCodepointLength(int codePoints) {
         return RandomizedTest.randomRealisticUnicodeOfCodepointLength(codePoints);
     }
 
+    public static String replaceUnicodeControlCharacters(String uniCodeStr, String toReplaceWith) {
+        // replace control characters (https://stackoverflow.com/questions/3438854/replace-unicode-control-characters/)
+        return uniCodeStr.replaceAll("\\p{Cc}", toReplaceWith);
+    }
+
+    public static String replaceUnicodeControlCharacters(String uniCodeStr) {
+        return replaceUnicodeControlCharacters(uniCodeStr, " ");
+    }
+
     /**
      * @param maxArraySize The maximum number of elements in the random array
      * @param stringSize The length of each String in the array
diff --git a/test/framework/src/main/java/org/opensearch/test/rest/OpenSearchRestTestCase.java b/test/framework/src/main/java/org/opensearch/test/rest/OpenSearchRestTestCase.java
index 3d74b0df5f283..07eec1f2504fb 100644
--- a/test/framework/src/main/java/org/opensearch/test/rest/OpenSearchRestTestCase.java
+++ b/test/framework/src/main/java/org/opensearch/test/rest/OpenSearchRestTestCase.java
@@ -626,7 +626,7 @@ protected static void wipeDataStreams() throws IOException {
             // We hit a version of ES that doesn't serialize DeleteDataStreamAction.Request#wildcardExpressionsOriginallySpecified field or
             // that doesn't support data streams so it's safe to ignore
             int statusCode = e.getResponse().getStatusLine().getStatusCode();
-            if (org.opensearch.common.collect.Set.of(404, 405, 500).contains(statusCode) == false) {
+            if (Set.of(404, 405, 500).contains(statusCode) == false) {
                 throw e;
             }
         }
diff --git a/test/framework/src/main/java/org/opensearch/test/transport/CapturingTransport.java b/test/framework/src/main/java/org/opensearch/test/transport/CapturingTransport.java
index f49f500d1431c..5e2c724e4e1e3 100644
--- a/test/framework/src/main/java/org/opensearch/test/transport/CapturingTransport.java
+++ b/test/framework/src/main/java/org/opensearch/test/transport/CapturingTransport.java
@@ -36,6 +36,7 @@
 import org.opensearch.common.util.concurrent.ConcurrentCollections;
 import org.opensearch.transport.Transport;
 import org.opensearch.transport.TransportRequest;
+import org.opensearch.transport.TransportRequestOptions;
 
 import java.util.ArrayList;
 import java.util.Collection;
@@ -54,12 +55,14 @@ public static class CapturedRequest {
         public final long requestId;
         public final String action;
         public final TransportRequest request;
+        public final TransportRequestOptions options;
 
-        CapturedRequest(DiscoveryNode node, long requestId, String action, TransportRequest request) {
+        CapturedRequest(DiscoveryNode node, long requestId, String action, TransportRequest request, TransportRequestOptions options) {
             this.node = node;
             this.requestId = requestId;
             this.action = action;
             this.request = request;
+            this.options = options;
         }
     }
 
@@ -123,6 +126,16 @@ public void clear() {
     }
 
     protected void onSendRequest(long requestId, String action, TransportRequest request, DiscoveryNode node) {
-        capturedRequests.add(new CapturingTransport.CapturedRequest(node, requestId, action, request));
+        capturedRequests.add(new CapturingTransport.CapturedRequest(node, requestId, action, request, null));
+    }
+
+    protected void onSendRequest(
+        long requestId,
+        String action,
+        TransportRequest request,
+        DiscoveryNode node,
+        TransportRequestOptions options
+    ) {
+        capturedRequests.add(new CapturingTransport.CapturedRequest(node, requestId, action, request, options));
     }
 }
diff --git a/test/framework/src/main/java/org/opensearch/test/transport/MockTransport.java b/test/framework/src/main/java/org/opensearch/test/transport/MockTransport.java
index e1e5bcc968047..5bfc8879ecbc6 100644
--- a/test/framework/src/main/java/org/opensearch/test/transport/MockTransport.java
+++ b/test/framework/src/main/java/org/opensearch/test/transport/MockTransport.java
@@ -188,13 +188,23 @@ public DiscoveryNode getNode() {
             public void sendRequest(long requestId, String action, TransportRequest request, TransportRequestOptions options)
                 throws TransportException {
                 requests.put(requestId, Tuple.tuple(node, action));
-                onSendRequest(requestId, action, request, node);
+                onSendRequest(requestId, action, request, node, options);
             }
         };
     }
 
     protected void onSendRequest(long requestId, String action, TransportRequest request, DiscoveryNode node) {}
 
+    protected void onSendRequest(
+        long requestId,
+        String action,
+        TransportRequest request,
+        DiscoveryNode node,
+        TransportRequestOptions options
+    ) {
+        onSendRequest(requestId, action, request, node);
+    }
+
     @Override
     public void setMessageListener(TransportMessageListener listener) {
         if (this.listener != null) {
diff --git a/test/framework/src/main/java/org/opensearch/transport/AbstractSimpleTransportTestCase.java b/test/framework/src/main/java/org/opensearch/transport/AbstractSimpleTransportTestCase.java
index ec88cd0201db5..b8f7dbd88570d 100644
--- a/test/framework/src/main/java/org/opensearch/transport/AbstractSimpleTransportTestCase.java
+++ b/test/framework/src/main/java/org/opensearch/transport/AbstractSimpleTransportTestCase.java
@@ -2109,7 +2109,9 @@ public void testRegisterHandlerTwice() {
             "internal:action1",
             randomFrom(ThreadPool.Names.SAME, ThreadPool.Names.GENERIC),
             TestRequest::new,
-            (request, message, task) -> { throw new AssertionError("boom"); }
+            (request, message, task) -> {
+                throw new AssertionError("boom");
+            }
         );
         expectThrows(
             IllegalArgumentException.class,
@@ -2117,7 +2119,9 @@ public void testRegisterHandlerTwice() {
                 "internal:action1",
                 randomFrom(ThreadPool.Names.SAME, ThreadPool.Names.GENERIC),
                 TestRequest::new,
-                (request, message, task) -> { throw new AssertionError("boom"); }
+                (request, message, task) -> {
+                    throw new AssertionError("boom");
+                }
             )
         );
 
@@ -2125,7 +2129,9 @@ public void testRegisterHandlerTwice() {
             "internal:action1",
             randomFrom(ThreadPool.Names.SAME, ThreadPool.Names.GENERIC),
             TestRequest::new,
-            (request, message, task) -> { throw new AssertionError("boom"); }
+            (request, message, task) -> {
+                throw new AssertionError("boom");
+            }
         );
     }