diff --git a/packages/@aws-cdk/aws-codedeploy/lib/server/deployment-group.ts b/packages/@aws-cdk/aws-codedeploy/lib/server/deployment-group.ts
index 2babdecf478be..4e1a436ef9b77 100644
--- a/packages/@aws-cdk/aws-codedeploy/lib/server/deployment-group.ts
+++ b/packages/@aws-cdk/aws-codedeploy/lib/server/deployment-group.ts
@@ -356,7 +356,7 @@ export class ServerDeploymentGroup extends ServerDeploymentGroupBase {
           'if [ -z "$PKG_CMD" ]; then',
           'PKG_CMD=apt-get',
           'else',
-          'PKG=CMD=yum',
+          'PKG_CMD=yum',
           'fi',
           '$PKG_CMD update -y',
           'set +e', // make sure we don't exit on the next command failing (we check its exit code below)
@@ -367,8 +367,7 @@ export class ServerDeploymentGroup extends ServerDeploymentGroupBase {
           '$PKG_CMD install -y ruby',
           'fi',
           'AWS_CLI_PACKAGE_NAME=awscli',
-          'if [[ "$PKG_CMD" = "yum" ]];',
-          'then',
+          'if [ "$PKG_CMD" = "yum" ]; then',
           'AWS_CLI_PACKAGE_NAME=aws-cli',
           'fi',
           '$PKG_CMD install -y $AWS_CLI_PACKAGE_NAME',
diff --git a/packages/@aws-cdk/aws-codedeploy/test/server/integ.deployment-group.expected.json b/packages/@aws-cdk/aws-codedeploy/test/server/integ.deployment-group.expected.json
index 1f5d3d109128d..c5ae20b9ac145 100644
--- a/packages/@aws-cdk/aws-codedeploy/test/server/integ.deployment-group.expected.json
+++ b/packages/@aws-cdk/aws-codedeploy/test/server/integ.deployment-group.expected.json
@@ -659,7 +659,7 @@
             "Fn::Join": [
               "",
               [
-                "#!/bin/bash\nset +e\nPKG_CMD=`which yum 2>/dev/null`\nset -e\nif [ -z \"$PKG_CMD\" ]; then\nPKG_CMD=apt-get\nelse\nPKG=CMD=yum\nfi\n$PKG_CMD update -y\nset +e\n$PKG_CMD install -y ruby2.0\nRUBY2_INSTALL=$?\nset -e\nif [ $RUBY2_INSTALL -ne 0 ]; then\n$PKG_CMD install -y ruby\nfi\nAWS_CLI_PACKAGE_NAME=awscli\nif [[ \"$PKG_CMD\" = \"yum\" ]];\nthen\nAWS_CLI_PACKAGE_NAME=aws-cli\nfi\n$PKG_CMD install -y $AWS_CLI_PACKAGE_NAME\nTMP_DIR=`mktemp -d`\ncd $TMP_DIR\naws s3 cp s3://aws-codedeploy-",
+                "#!/bin/bash\nset +e\nPKG_CMD=`which yum 2>/dev/null`\nset -e\nif [ -z \"$PKG_CMD\" ]; then\nPKG_CMD=apt-get\nelse\nPKG_CMD=yum\nfi\n$PKG_CMD update -y\nset +e\n$PKG_CMD install -y ruby2.0\nRUBY2_INSTALL=$?\nset -e\nif [ $RUBY2_INSTALL -ne 0 ]; then\n$PKG_CMD install -y ruby\nfi\nAWS_CLI_PACKAGE_NAME=awscli\nif [ \"$PKG_CMD\" = \"yum\" ]; then\nAWS_CLI_PACKAGE_NAME=aws-cli\nfi\n$PKG_CMD install -y $AWS_CLI_PACKAGE_NAME\nTMP_DIR=`mktemp -d`\ncd $TMP_DIR\naws s3 cp s3://aws-codedeploy-",
                 {
                   "Ref": "AWS::Region"
                 },
@@ -884,4 +884,4 @@
       "Default": "/aws/service/ami-amazon-linux-latest/amzn-ami-hvm-x86_64-gp2"
     }
   }
-}
+}
\ No newline at end of file
diff --git a/packages/@aws-cdk/aws-codedeploy/test/server/test.deployment-group.ts b/packages/@aws-cdk/aws-codedeploy/test/server/test.deployment-group.ts
index 6aa102e97da11..5eaffc0de5741 100644
--- a/packages/@aws-cdk/aws-codedeploy/test/server/test.deployment-group.ts
+++ b/packages/@aws-cdk/aws-codedeploy/test/server/test.deployment-group.ts
@@ -81,7 +81,7 @@ export = {
             'Fn::Join': [
               '',
               [
-                '#!/bin/bash\nset +e\nPKG_CMD=`which yum 2>/dev/null`\nset -e\nif [ -z "$PKG_CMD" ]; then\nPKG_CMD=apt-get\nelse\nPKG=CMD=yum\nfi\n$PKG_CMD update -y\nset +e\n$PKG_CMD install -y ruby2.0\nRUBY2_INSTALL=$?\nset -e\nif [ $RUBY2_INSTALL -ne 0 ]; then\n$PKG_CMD install -y ruby\nfi\nAWS_CLI_PACKAGE_NAME=awscli\nif [[ "$PKG_CMD" = "yum" ]];\nthen\nAWS_CLI_PACKAGE_NAME=aws-cli\nfi\n$PKG_CMD install -y $AWS_CLI_PACKAGE_NAME\nTMP_DIR=`mktemp -d`\ncd $TMP_DIR\naws s3 cp s3://aws-codedeploy-',
+                '#!/bin/bash\nset +e\nPKG_CMD=`which yum 2>/dev/null`\nset -e\nif [ -z "$PKG_CMD" ]; then\nPKG_CMD=apt-get\nelse\nPKG_CMD=yum\nfi\n$PKG_CMD update -y\nset +e\n$PKG_CMD install -y ruby2.0\nRUBY2_INSTALL=$?\nset -e\nif [ $RUBY2_INSTALL -ne 0 ]; then\n$PKG_CMD install -y ruby\nfi\nAWS_CLI_PACKAGE_NAME=awscli\nif [ "$PKG_CMD" = "yum" ]; then\nAWS_CLI_PACKAGE_NAME=aws-cli\nfi\n$PKG_CMD install -y $AWS_CLI_PACKAGE_NAME\nTMP_DIR=`mktemp -d`\ncd $TMP_DIR\naws s3 cp s3://aws-codedeploy-',
                 {
                   'Ref': 'AWS::Region',
                 },