RabbitMQ 4.0.7

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

Core Broker

Bug Fixes

• Classic queue message store did not remove segment files with large messages (over 4 MB) in some cases.

• A node with Khepri enabled would fail to start if its metadata store contained an exclusive queue with at least one binding.

Enhancements

• Reduced memory usage and GC pressure for workloads where large (4 MB or greater) messages were published to classic queues.

CLI Tools

Deprecations

• rabbitmq-streams set_stream_retention_policy is now a no-op.

  It was a leftover from the early days of streams. The modern and optimal way of configuring stream retention is via a policy.

Prometheus Plugin

Enhancements

• New labels make it possible to differentiate between the metrics with the same name scraped from the aggregated metric endpoint and the per-object metric endpoint.

Management Plugin

Bug Fixes

• Who help tooltips were not updated for 4.0.x.

Enhancements

• Consumer count is a new column that can be enabled for the channels table on the tab of the same name.

Caching Authentication and Authorization Backend Plugin

Enhancements

• rabbitmqctl clear_auth_backend_cache is a new command that clears the cache maintained by the plugin.

Dependency Changes

• ra was upgraded to 2.15.2

RabbitMQ 4.0.6

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

Core Broker

Bug Fixes

• When a quorum queue leader has changed, followers were not always notified of unapplied [for/by them] log commands.

• Default cluster formation timeout with Khepri now matches that of Mnesia (5 minutes by default).

• When stream consumer was cancelled, an internal event was not emitted.

• Stream consumer metrics were not cleared when its respective connection was closed.

• Quorum queues could return a list of members (replicas) with duplicates in some cases.

• Classic queues with priorities could run into an exception.

• Corrected a log message.

Enhancements

• A new mechanism for protecting a virtual host from deletion using metadata.

CLI Tools

Bug Fixes

• rabbitmqctl import_definitions hanged when definitions were provided via the standard input instead of a file.

Enhancements

• rabbitmqadmin v2 has matured enough to recommend it over the original version of the tool

• rabbitmq-diagnostics CLI documentation was improved to clarify that all certificates discovered will be checked for expiration.

• New health checks for metadata store initialization:

  1. rabbitmq-diagnostics check_if_metadata_store_is_initialized
  2. rabbitmq-diagnostics check_if_metadata_store_is_initialized_with_data

Prometheus Plugin

Bug Fixes

• Improved metric description.

Management Plugin

Bug Fixes

• Pagination-related sections of the HTTP API reference were clarified to explain that the maximum page size cannot exceed 500.

• Empty channel_details objects are now serialized as empty objects and not empty arrays.

Enhancements

• New health checks for metadata store initialization:

  1. GET /api/health/checks/metadata-store/initialized
  2. GET /api/health/checks/metadata-store/initialized/with-data

Deprecations

• The original HTTP API One True Health Check™ is now a no-op. A comparable "mega health check" has long been deprecated in CLI tools and was made a no-op in 4.0.0.

  This endpoint was using a deprecated feature: a classic non-exclusive transient (non-durable) queue.

  See Health Checks for modern focused alternatives.

Consul Peer Discovery Plugin

Enhancements

• cluster_formation.registration.enabled is a new configuration setting that allows the backend to skip registration.

  This is useful when Consul is used for peer discovery but a different tool such as Nomad is used to keep track of the services and their registration, unregistration.

Erlang AMQP 1.0 Client

Bug Fixes

• Purging an non-existing queue now returns a 404 response.

Dependency Changes

• ra was upgraded to 2.15.1

• observer_cli was upgraded to 1.8.2