v25.4 changes to logging channels (#20434)

- In logging-overview.md, (a) added log.channel_compatibility_mode.enabled section, (b) updated Logging channels table with notes with link to log.channel_compatibility_mode.enabled, and (c) updated Log destinations table.
- In configure-logs.md, logging-use-cases.md, and log-sql-activity-to-datadog, added note with link to log.channel_compatibility_mode.enabled.
- In configure-logs.md, added kv-exec to Default logging configuration.

* Incorporated Kevin’s feedback.
* Incorporated Mike’s feedback.

Author: florence-crl

src/current/v25.4/configure-logs.md

@@ -15,6 +15,12 @@ This page describes how to configure CockroachDB logs with the [`--log` or `log-
 
 For examples of how these settings can be used in practice, see [Logging Use Cases]({% link {{ page.version.version }}/logging-use-cases.md %}).
 
+{{site.data.alerts.callout_info}}
+In a future major release, certain events will be directed by default to new [logging channels]({% link {{ page.version.version }}/logging-overview.md %}#logging-channels).
+
+To prepare for the change and assess potential downstream impacts on your logging setup and pipelines, review the [`log.channel_compatibility_mode.enabled`]({% link {{ page.version.version }}/logging-overview.md %}#log-channel_compatibility_mode-enabled) cluster setting. After reviewing the documentation, set `log.channel_compatibility_mode.enabled` to `false` in a non-production environment.
+{{site.data.alerts.end}}
+
 ## Flag
 
 To configure the logging behavior of a `cockroach` command, include one of these flags with the command:
@@ -865,6 +871,19 @@ sinks:
       redactable: true
       exit-on-error: true
       buffering: NONE
+    kv-exec:
+      channels: {INFO: [KV_EXEC]}
+      dir: /cockroach-data/logs
+      max-file-size: 10MiB
+      max-group-size: 100MiB
+      file-permissions: "0640"
+      buffered-writes: true
+      filter: INFO
+      format: crdb-v2
+      redact: false
+      redactable: true
+      exit-on-error: true
+      buffering: NONE
     pebble:
       channels: {INFO: [STORAGE]}
       dir: /cockroach-data/logs

src/current/v25.4/log-sql-activity-to-datadog.md

@@ -7,6 +7,12 @@ docs_area: manage
 
 This tutorial describes how to configure logging of telemetry events, including [`sampled_query`]({% link {{ page.version.version }}/eventlog.md %}#sampled_query) and [`sampled_transaction`]({% link {{ page.version.version }}/eventlog.md %}#sampled_query), to [Datadog](https://www.datadoghq.com/) for finer granularity and long-term retention of SQL activity. The `sampled_query` and `sampled_transaction` events contain common SQL event and execution details for [statements]({% link {{ page.version.version }}/sql-statements.md %}) and [transactions]({% link {{ page.version.version }}/transactions.md %}).
 
+{{site.data.alerts.callout_info}}
+`sampled_query` and `sampled_transaction` events, which are sent by default to the [`TELEMETRY`]({% link {{ page.version.version }}/logging-overview.md %}#telemetry) channel in {{ page.version.version }} and earlier versions, will instead be routed by default to the [`SQL_EXEC`]({% link {{ page.version.version }}/logging-overview.md %}#sql_exec) channel in a future major release.
+
+To prepare for the change and assess potential downstream impacts on your logging setup and pipelines, review the [`log.channel_compatibility_mode.enabled`]({% link {{ page.version.version }}/logging-overview.md %}#log-channel_compatibility_mode-enabled) cluster setting. After reviewing the documentation, set `log.channel_compatibility_mode.enabled` to `false` in a non-production environment to log `sampled_query` and `sampled_transaction` events to the [SQL_EXEC]({% link {{ page.version.version }}/logging-overview.md %}#sql_exec) channel.
+{{site.data.alerts.end}}
+
 CockroachDB supports a built-in integration with Datadog which sends these events as logs via the [Datadog HTTP API](https://docs.datadoghq.com/api/latest/logs/). This integration is the recommended path to achieve high throughput data ingestion, which will in turn provide more query and transaction events for greater workload observability.
 
 {{site.data.alerts.callout_info}}