Merge pull request #9823 from rabbitmq/mergify/bp/v3.12.x/pr-9822

3.12.8 release notes (backport #9822)

Author: michaelklishin

release-notes/3.12.8.md

@@ -0,0 +1,70 @@
+RabbitMQ `3.12.8` is a maintenance release in the `3.12.x` [release series](https://www.rabbitmq.com/versions.html).
+
+Please refer to the upgrade section from the [3.12.0 release notes](https://github.com/rabbitmq/rabbitmq-server/releases/tag/v3.12.0)
+if upgrading from a version prior to 3.12.0.
+
+This release requires Erlang 25 and supports Erlang versions up to `26.1.x`.
+[RabbitMQ and Erlang/OTP Compatibility Matrix](https://www.rabbitmq.com/which-erlang.html) 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](https://github.com/rabbitmq/rabbitmq-server/releases/tag/v3.12.0) first.
+
+
+## Changes Worth Mentioning
+
+Release notes can be found on GitHub at [rabbitmq-server/release-notes](https://github.com/rabbitmq/rabbitmq-server/tree/v3.12.x/release-notes).
+
+
+### Core Server
+
+#### Bug Fixes
+
+ * Avoids a potential exception in the `autoheal` partition handler.
+
+   Contributed by @Ayanda-D.
+
+   GitHub issue: [#9818](https://github.com/rabbitmq/rabbitmq-server/pull/9818)
+
+#### Enhancements
+
+ * `raft.segment_max_entries` is now validated to prevent the value from overflowing its 16-bit segment file field.
+   Maximum supported value is now ``65535.
+
+   GitHub issue: [#9733](https://github.com/rabbitmq/rabbitmq-server/issues/9733)
+
+
+### Shovel Plugin
+
+#### Enhancements
+
+ * Significantly faster Shovel startup in environments where there are many of them (one thousand or more).
+
+   GitHub issue: [#9796](https://github.com/rabbitmq/rabbitmq-server/pull/9796)
+
+
+### AMQP 1.0 Erlang Client
+
+#### Enhancements
+
+ * User-provided credentials are now obfuscated using an one-off key pair generated on node boot.
+   This keeps sensitive client state information from being logged by the runtime exception logger.
+
+   GitHub issue: [#9777](https://github.com/rabbitmq/rabbitmq-server/pull/9777)
+
+
+## Dependency Upgrades
+
+None in this release.
+
+
+## Source Code Archives
+
+To obtain source code of the entire distribution, please download the archive named `rabbitmq-server-3.12.8.tar.xz`
+instead of the source tarball produced by GitHub.