rabbitmq-server/release-notes/3.12.2.md

RabbitMQ 3.12.2 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

Enhancements

• Free disk space monitor on Windows is now more selective in what errors are logged.

  GitHub issue: #8837

Bug Fixes

• Queue recovery on node restart in certain conditions could run into an exception

  GitHub issue: #8746

• file_handle_cache operations are now safer when handling non-existent keys.

  GitHub issue: #8784

• Fixed a potential resource leak in at-least-once dead lettering from quorum queues.

  GitHub issue: #8799

CLI Tools

Enhancements

• A new command, rabbitmqctl deactivate_free_disk_space_monitoring, can be used to (temporarily or permanently) disable free disk space monitoring on a node.

  To re-activate it, use rabbitmqctl activate_free_disk_space_monitoring.

  GitHub issue: #8801

AMQP 1.0 Plugin

Bug Fixes

• AMQP 1.0 clients that try to publish in a way that results in the message not being routed anywhere are now notified with a more sensible settlement status.

  GitHub issue: #7823

Prometheus Plugin

Enhancements

• Prometheus scraping API endpoints now support optional authentication.

  Contributed by @SimonUnge (AWS).

  GitHub issue: #8661

• The plugin now filters out values that are undefined or NaN, simply excluding them from the API endpoint response.

  Previously, if a metric was not computed for any reason (e.g. free disk space monitor was disabled on the node), its value could end up being rendered as undefined or NaN, two values that Prometheus scrapers cannot handle (for numerical types such as gauges).

  GitHub issue: #8740

Management Plugin

Bug Fixes

• It was not possible to close a table column selection pane on screens that had little vertical space.

  Contributed by @Antsthebul.

  GitHub issue: #8701

STOMP Plugin

Bug Fixes

• This is a potentially breaking change.

  The plugin will now enforce maximum STOMP frame size. Frames larger than that size will be rejected. The default maximum size is 4 MiB. It can be increased or decreased:

  # increase maximum supported STOMP frame size to 10 MiB
  stomp.max_frame_size = 10485760
  

  To reduce it from the default 4 MiB to 2 MiB:

  # 2 MiB
  stomp.max_frame_size = 2097152
  

  GitHub issue: #8802

Shovel Plugin

Bug Fixes

• Shovel will gracefully stop when its destination (target) does not exist. Such shovels will then be periodically restarted to retry.

  Contributed by @markus812498 (CloudAMQP).

  GitHub issue: #8697

Web MQTT Plugin

Enhacements

• It is now possible to opt in to deactivate file handle cache use in the plugin:

  web_mqtt.use_file_handle_cache = false
  

  GitHub issue: #8790

Web STOMP Plugin

Enhacements

• It is now possible to opt in to deactivate file handle cache use in the plugin:

  web_stomp.use_file_handle_cache = false
  

  GitHub issue: #8790

Dependency Upgrades

• ra was upgraded to 2.6.3

Source Code Archives

To obtain source code of the entire distribution, please download the archive named rabbitmq-server-3.12.2.tar.xz instead of the source tarball produced by GitHub.