Fleet Server release notes

Stack

Review the changes, fixes, and more in each version of Fleet Server.

To check for security updates, go to Security announcements for the Elastic Stack.

• Add OTel collector properties to policy schema. #5169 #5241

  Add OTel collector properties to the policy schema. This way policies defined in Fleet that include this data are forwarded to agents.

• Add agent_policy_id and policy_revision_idx to checkin requests. #5501 #6446

  Add the agent_policy_id and policy_revision_idx attributes to checkin request bodies so an agent is able to inform fleet-server of its exact policy. These details will replace the need for an ack on policy_change actions, and will be used to determine when to send a policy change when there is a new revision available, or when the agent is reassigned to a different policy. Add a server setting under feature_flags.ignore_checkin_policy_id that disables this behavour and restores the previous approach.

• Refactor bulk checkin handler. #5493

  Refactor the bulk checkin handler to allow for future extensions

• Add credentials to OTel Elasticsearch exporters. #5469

  When a policy includes OTel configuration with Elasticsearch exporters, it configures their credentials using the credentials in the Elasticsearch output.

• Update Golang version to v1.25.1. #5562

• Update Go version to v1.25.1. #5562

• Reset trace links on bulk items when returning to pool. #5317

• Restore connection limiter. #5372

  Restore connection level limiter to prevent OOM incidents. This limiter is used in addition to the request-level throttle so that when our in-flight requests reaches max_connections, a 429 is returned. If the total connections the server uses is over max_connections*1.1 the server drops the connection before the TLS handshake.

• Build fleet-server as fully static binary to restore OS matrix compatibility. #5392 #5262

• Fix 503 handling in enrollment. #5232 #5197
• Remove extra ES search when preparing agent policy. #5283

No new features, enhancements, or fixes.

• Fix upgrade details download_rate as string handling. #5198 #5214 #5183 #5176 #5164

• Add ability for enrollment to take an agent ID. #4290 #4226

• Add migrate-action. #4786

  Added new MIGRATE action type for moving agent to different cluster.

• Clear agent.upgrade_attempts when upgrade is complete. #4528

  The new AutomaticAgentUpgradeTask Kibana task sets the upgrade_attempts property in agents it upgrades. This property is used to track upgrade retries and should therefore be cleared when the upgrade is complete.

• Make pbkdf2 settings validation FIPS compliant. #4542

• Update Go to v1.24.3. #4891

• Add version metadata to version command output. #4820

  Add commit, buildtime, and FIPS distribution indicators to output of version command. Add fips-distribution attribute to initial startup log.

• Add rollback attribute to upgrade actions in preparation for enabling upgrade rollbacks in a future release. #4838

• Upgrade golang.org/x/net to v0.34.0 and golang.org/x/crypto to v0.32.0. #4405

• Fix host parsing in Elasticsearch output diagnostics. #4765

• Redact output in bootstrap config logs. #4775

• Mutex protection for remote bulker config. #4776

  Use existing remote bulker mutex to control access to remote bulker configs.

• Enable dead code elimination. #4784

  Add grpcnotrace build tags and ensure DCE (dead code elimination) is enabled. Reduce binary size by 34%

• Include the base error for json decode error responses. #5069

• Update Go version to v1.25.1. #5562

• Reset trace links on bulk items when returning to pool. #5317

• Restore connection limiter. #5372

  Restore connection level limiter to prevent OOM incidents. This limiter is used in addition to the request-level throttle so that once our in-flight requests reaches max_connections a 429 is returned, but if the total connections the server uses is over max_connections*1.1 the server drops the connection before the TLS handshake.

• Build fleet-server as fully static binary to restore OS matrix compatibility. #5392 #5262

• Fix 503 handling in enrollment. #5232 #5197
• Remove extra ES search when preparing agent policy. #5283