Project: RabbitMQ (App Definition and Development / Streaming & Messaging)
File: 3.8.0.md

RabbitMQ `3.8.0` is a feature release. It contains several major improvements in areas of data safety, replication, observability, and ease of upgrades. Some highlight features are * Built-in with a set of Grafana dashboards to complement it * New authentication and authorisation tokens and scopes A recorded webinar, , covers some of the highlights in this release. Several features in this release are backed by a new Raft implementation for Erlang and Elixir, . This release or later. `22.x` series is recommended. explains what package repositories and tools can be used to provision latest patch versions of Erlang `21.3.x` and `22.x`. RabbitMQ 3.8.0 nodes can run alongside `3.7.18` or later `3.7.x` nodes. No 3.8.0-specific features would be available in a mixed version cluster. Mixed versions are meant to simplify rolling upgrades and not meant to be running for long periods of time. See the for documentation on upgrades. When upgrading to this release and upgrading Erlang to 21.x or later at the same time, extra care has to be taken. Since CLI tools from RabbitMQ releases older than 3.7.7 will fail on Erlang 21 or later, RabbitMQ must be upgraded before Erlang. See the for documentation on upgrades and for release notes of other releases. Client libraries that were compatible with RabbitMQ `3.7.x` will be compatible with `3.8.0`. Any questions about this release, upgrades or RabbitMQ in general are welcome on the . built on top of the for data safety, more predictable failure recovery, more efficient synchronisation of new and recovered followers, and parallel replication. allow for mixed-version clusters and safer rolling upgrades. makes it possible to run a set of consumers for redundancy while ensuring that only one consumer is getting deliveries. New metric: dropped unroutable messages. Spotting faulty publishers and routing topology issues is now easier. GitHub issue: New metrics: and . GitHub issue: Quorum queues support redelivery tracking, which can be used by consumers to protect themselves from poison message redeliveries. GitHub issue: New queue overflow behaviour: `reject-publish-dlx`. It is identical to `reject-publish` but also dead letters rejected messages. GitHub issue: Default bindings are now explicit instead of being rows in the internal data store. That means that high queue churn results in significantly less binding churn, reducing lock contention on schema database tables, and peak schema operation latencies with it. GitHub issue: is a new public API module that should be used to access queue state instead of using queue state records directly. This allows the record to evolve a lot more rapidly with fewer or no code changes in the plugins that access queue state. `authn` and `authz` functions now have access to additional (e.g. protocol-specific) context information. GitHub issue: Backing queue interface now exposes a function for message deduplication. Plugins now can track duplicate messages in a way that makes it possible to negatively confirm duplicates back to the publisher. Contributed by Matteo Cafasso. GitHub issue:

New style configuration format is now more forgiving: it will ignore lines that only contain whitespace and tab characters, as well as leading and trailing whitespace. GitHub issue: Maximum message size is now configurable. The default was reduced to 128 MiB.e GitHub issue: Most bug fixes in this release previously shipped in . The list below contains community contributions and most important issues that were not backported to `3.7.x` releases. Queue index consistency and safety improvements. Contributed by @tomyouyou. GitHub issues: , , . More user-friendly `rabbitmq-diagnostics status` output. GitHub issue: New `help` command. GitHub issue: A new set of fine-grained commands. GitHub issue: New tool, `rabbitmq-queues`, with commands that display Raft state metrics and manage nodes that host quorum queue replicas. GitHub issues: , Feature flag status reporting. GitHub issue: `rabbitmq-diagnostics cipher_suites` now uses OpenSSL cipher suite format by default. GitHub issue: Metric collection and visualisation in management UI now can be disabled in favor of built-in Prometheus support and Grafana dashboard from Team RabbitMQ. GitHub issue: Feature flag management interface. Quorum Queue support. Single Active Consumer support. GitHub issue: Support for more TLS options. GitHub issue: OAuth 2.0 Single Sign On support for GitHub issue: Username and password-based Basic HTTP Auth authentication for API operations now can be disabled in favor of OAuth 2.0 Single Sign On via . GitHub issue: Most bug fixes in this release previously shipped in . The list below contains most prominent fixes. Sensitive values in Shovel connection state (namely, the connection credentials) are now stored in encrypted form. This avoids unintentional credential logging by the runtime (exception logger) at the cost of making troubleshooting authentication failures harder. GitHub issue: Most bug fixes in this release previously shipped in . The list below contains most prominent fixes. Sensitive values in federation link state (namely, the connection credentials) are now stored in encrypted form. This avoids unintentional credential logging by the runtime (exception logger) at the cost of making troubleshooting authentication failures harder. GitHub issue: Initial release. GitHub repository: Client ID tracking is now cluster-wide (state is replicated across all nodes). A majority of nodes is required for client connections to be accepted. This is a consequence of the neew consistency-oriented design. GitHub issue: Most bug fixes in this release previously shipped in . The list below contains most prominent fixes. Maximum concurrent client connection limit now defaults to "infinity" (so, there is no limit). GitHub issue: Most bug fixes in this release previously shipped in . The list below contains most prominent fixes. Maximum concurrent client connection limit now defaults to "infinity" (so, there is no limit). GitHub issue: Most bug fixes in this release previously shipped in . The list below contains most prominent fixes. Sensitive values in connection state (namely, the connection credentials) are now stored in encrypted form. This avoids unintentional credential logging by the runtime (exception logger) at the cost of making troubleshooting authentication failures harder. GitHub issue: 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-3.8.0.tar.xz`.