Project: RabbitMQ (App Definition and Development / Streaming & Messaging)
File: 3.8.10.md

Important: this release has been which addresses a couple of bugs specific to this release (`3.8.10`) All users are advised to consult the set of changes in this release but then upgrade straight to `3.8.11` or a newer version if available and skip this release. RabbitMQ `3.8.10` is a maintenance release. Besides containing several bug fixes, it introduces a couple new features for quorum queues. This release . This release or . Erlang 21.3 . `22.3` or `23.1` releases are recommended. explains what package repositories and tools can be used to provision latest patch versions of Erlang `22.3.x`. This release deprecates build into the management plugin. The feature still exists but is no longer documented or tested. Please switch to the built-in definition import mechanism: ``` ini management.load_definitions = /path/to/definitions/file.json ``` to ``` ini load_definitions = /path/to/definitions/file.json ``` Definition import in the management plugin (`management.load_definitions`) will be removed in a future RabbitMQ release. See upgrade and compatibility notes first if upgrading from an earlier release series (e.g. `3.7.x`). See the for general documentation on upgrades and for release notes of other releases. When upgrading to this release from `3.7.15` or an older version, extra care has to be taken. Because older RabbitMQ CLI tools can be incompatible with Erlang 22+ releases, RabbitMQ must be upgraded at the same time as Erlang. Alternatively the node can be upgraded to `3.7.18` on Erlang 21.3 first, then Erlang 22.x or 23.x, then RabbitMQ to the most recent 3.8.x release. Any questions about this release, upgrades or RabbitMQ in general are welcome on the and . Starting with `3.8.0`, an unintentionally introduced assertion could prevent classic mirrored queue mirrors from starting successfully in case the primary replica changed concurrently with their startup. GitHub issue: Repeated polling of a quorum queue with `basic.get` that yielded an empty response could result in an unbounded growth of log segment files on on disk. GitHub issue: RabbitMQ core plugin activation was revisited to be closer to that of `3.7.x`. This does not any related improvements w.r.t. definition import, e.g. those introudced in . GitHub issue: Syslog dependency was not started correctly. This meant no log messages were sent to Syslog. GitHub issue: `rabbitmq-diagnostics checkifnodeisquorum_critical` returned a false positive for a node . Given the refinement to the `rabbitmq-upgrade drain` command in , `rabbitmq-diagnostics checkifnodeisquorum_critical` now will unconditionally return a success if target node is under

GitHub issue: Queues could update their internal bookkeeping state incorrectly in some cases, leading to a `filehandlecache` operation exception. GitHub issue: now can use the max length overflow strategy. GitHub issue: now support . GitHub issue: Per-user connection and queue limits. This is similar to but, as the name suggests, these limits are associated for a given user. The limits are controlled using CLI tools or the HTTP API: ``` sh rabbitmqctl setuserlimits "user-e8d3f85c" '{"max-connections": 5, "max-channels": 10}' rabbitmqctl clearuserlimits "user-e8d3f85c" "max-connections" rabbitmqctl clearuserlimits "user-e8d3f85c" "all" ``` Contributed by Erlang Solutions, sponsored by . GitHub issue: , TLSv1.3 is no longer considered experimental (on Erlang 23) and excluded from TLS listener configuration. GitHub issue: When a node is put under maintenance, it will now stop all local quorum queue replicas after completing leadership transfer. This means that no quorum queue replicas on the node will be considered for leader elections. GitHub issue: Nodes now keep track of failed client authentication attempts and expose it as a metric via both the and the HTTP API at `GET /api/auth/attempts/{node}`. The tracking is done for every cluster node individually. The protocols that support authentication attempt tracking right now are AMQP 0-9-1, AMQP 1.0 and MQTT. GitHub issue: `bypasspemcache` is a new configuration key that makes it possible to disable the cache of PEM files . This rotated certificates quicker to detect for nodes but can also increase latency for inbound TLS connections, e.g. under . GitHub issue: Definition import now safely handles some missing queue object arguments. GitHub issue: `rabbitmq.conf` schema now allows for to be set to zero. When this value is used, peer certificate must be in order for the verification to pass. GitHub issue: `RABBITMQIOTHREADPOOLSIZE` will no longer be respected by RabbitMQ nodes. It with supported Erlang versions and will simplify output. GitHub issue: The `+K` is no longer used by RabbitMQ nodes as it has with supported Erlang versions. Contributed by Ayanda Dube (Erlang Solutions). GitHub issue: It is now possible to enable all feature flags in a single command: ``` sh rabbitmqctl enablefeatureflag all ``` Note that this will only enable the flags supported by all cluster members. GitHub issue: `rabbitmq-queues peek` is a new command that allows for peeking at a queue position. It is only supported by quorum queues (and not classic queues): ``` sh rabbitmq-queues peek --vhost "staging"

1" ``` GitHub issue: `rabbitmq-queues reclaimquorummemory` is a new command that forces Raft WAL compaction which in most cases should reduce memory footprint of a quorum queue: ``` sh rabbitmq-queues reclaimquorummemory --vhost "staging" "qq.1" ``` GitHub issue: `rabbitmqctl renameclusternode` failed with an error about a missing directory. GitHub issue: `rabbitmqctl export_definitions` exported optional binding arguments as blank. GitHub issue: Force removal of a node did not remove it from quorum queue member lists. GitHub issue: CLI tools now pick a unique identifier from a pool. Previously the pool of possible values was theoretically unbounded, which could result in an atom table exhaustion condition on long running nodes that had a lot of CLI tool invocations (e.g. CLI tools were used to collect monitoring data frequently). Such use of CLI tools for is not recommended: there are better options such as . GitHub issue: Raft-based client ID tracker is now significantly more efficient in handling failing or closed connections. This prevents potential on the node. GitHub issue: Federation links that failed to connect due to a TCP connection timeout . Other connection failure scenarios did not result in a leak. GitHub issue: An autodeleted Shovel would re-appear on other cluster nodes after the node that hosted it originally was restarted. GitHub issue: `GET /metrics/per-object` is a new endpoint that always returns , even if `GET /metrics` is configured to return aggregated results. GitHub issue: are now available through the HTTP API. GitHub issue: Quorum queue consumer counter on on the queue list page was not updated when consumers were cancelled or failed. GitHub issue: The aliveness check endpoint now responds with a `503 Service Unavailable` instead of a 500 when it cannot publish a test message, e.g. because a policy with zero message TTL was applied to all queues. GitHub issue: AWS API request errors are now propagated. This means that should an AWS API request fail, the peer discovery subsystem will retry it a limited number of times. Contributed by Stefan @stefanmoser Moser. GitHub issue: `amqp_channel:call/4` timeouts are now safly reconciled with connection-level timeouts. Contributed by Ayanda Dube. GitHub issue: Windows installer is now signed by a new (rolled) key. GitHub issue: The installer now correctly creates directories when RabbitMQ is installed to a different drive from the shell (`cmd.exe`). Contributed by Jiahao @Y2Nk4 Guo. GitHub issue: `credentials_obfuscation` was upgraded `ranch` is of `rabbit_common` Warning: The source code archive provided by GitHub only contains the source of the broker, not the plugins or the client libraries. Please download the archive named `rabbitmq-server-3.8.10.tar.xz`.