RabbitMQ - v3.12.5

RabbitMQ 3.12.5 is a maintenance release in the 3.12.x release series.

Please refer to the upgrade section from the 3.12.0 release notes
if upgrading from a version prior to 3.12.0.

This release requires Erlang 25 and supports Erlang versions up to 26.0.x.
RabbitMQ and Erlang/OTP Compatibility Matrix has more details on
Erlang version requirements for RabbitMQ.

Minimum Supported Erlang Version

As of 3.12.0, RabbitMQ requires Erlang 25. Nodes will fail to start on older Erlang releases.

Users upgrading from 3.11.x (or older releases) on Erlang 25 to 3.12.x on Erlang 26
(both RabbitMQ and Erlang are upgraded at the same time) must consult
the v3.12.0 release notes first.

Changes Worth Mentioning

Release notes can be found on GitHub at rabbitmq-server/release-notes.

Core Server

Bug Fixes

• Quorum queue leader changes are now correctly observed in certain network failure scenarios.

GitHub issues: #9241, #9227

• High consumer churn with reused consumer tag on quorum queues could result in some messages not being delivered
  after a period of time.

This did not affect environments where consumer churn does not exist or where it does but consumer tags vary.

GitHub issue: #9158

• Three environment variables, LOG_BASE, MNESIA_BASE, CONFIG_FILE, were not picked up when set in
  rabbitmq-env-conf.bat on Windows.

Gi9158issue: #9307

• Avoids a potential exception when autoheal partition handling process was initiated.

GitHub issue: #9222

• Avoids a potential exception in the credit flow subsystem.

Contributed by @Ayanda-D.

GitHub issue: #9433

• Classic queues v2 (CQv2) that had priorities enabled were reporting their storage version
  incorrectly.

Contributed by @gomoripeti (CloudAMQP).

GitHub issue: #9370

Enhancements

• Channels that had many thousands of consumers (usually due to a consumer leak in the application)
  now consume a lot less CPU resources when the channel is closed.

As part of this optimization, individual consumer.deleted internal events are no
longer emitted when a channel is closed, only a channel.closed event is. This also
help reduce audit event log size, since those consumer.deleted events provided
no useful information in this context.

Contributed by @SimonUnge (AWS).

GitHub issue: #9356

• Initial forward compatibility with later Erlang 26.x and 27.0 releases.

GitHub issue: #9485

• Nodes now log boot time at info level instead of debug. This piece of information
  can be useful during root cause analysis.

Contributed by @johanrhodin (CloudAMQP).

GitHub issue: #9466

• Channel interceptors (defined by plugins) now can return one more type of errors.

Contributed by @Ayanda-D.

GitHub issue: #9459

CLI Tools

Bug Fixes

• rabbitmqctl delete_queue now handles more queue replica failure scenarios
  (that were previously handled by client operations and the HTTP API but not CLI tools).

Contributed by @Ayanda-D.

GitHub issue: #9324

• rabbitmq-streams delete_replica now handles scenarios where the replica is hosted
  on a node that is not accessiable (reachable).

GitHub issue: #9282

MQTT Plugin

Bug Fixes

• If a socket write fails, close the connection quickly to avoid producing a lot of
  log noise.

GitHub issue: #9281

AMQP 1.0 Plugin

Bug Fixes

• Listing AMQP 1.0 connections in a system that had both AMQP 1.0 and AMQP 0-9-1 clients connected
  resulted in exceptions logged and partial results returned to CLI tools.

GitHub issue: #9371

Prometheus Plugin

Enhancements

• The plugin now exposes a new gauge, rabbitmq_unreachable_cluster_peers_count, that indicates how many cluster
  peers cannot be reached by this node.

Contributed by @gomoripeti (CloudAMQP).

GitHub issues: #2508, #9465

Dependency Upgrades

• osiris was upgraded to 1.6.7

Dependency Upgrades

None in this release.

Source Code Archives

To obtain source code of the entire distribution, please download the archive named rabbitmq-server-3.12.5.tar.xz
instead of the source tarball produced by GitHub.