4.2.0 updates for rc.1

Author: michaelklishin

release-notes/4.2.0.md

@@ -1,6 +1,6 @@
-## RabbitMQ 4.2.0-beta.5
+## RabbitMQ 4.2.0-rc.1
 
-RabbitMQ `4.2.0-beta.5` is a preview of a feature release.
+RabbitMQ `4.2.0-rc.1` is a preview of a feature release.
 
 
 ## Breaking Changes and Compatibility Notes
@@ -23,6 +23,12 @@ Starting with RabbitMQ 4.2, if an AMQP 0.9.1 Direct Reply-To responder (RPC serv
 Whether the requester (RPC client) is still there to consume the reply is not checked at routing time.
 In other words, if the responder publishes to only this queue name, then the message will be considered "routed" and RabbitMQ will therefore not send a `basic.return`.
 
+### Very Rarely Used `*.cacerts` Settings are Removed from `rabbitmq.conf`
+
+`*.cacerts` (not to be confused with `cacertfile`) settings in `rabbitmq.conf` did not have the expected effect and were removed
+to eliminate confusion.
+
+
 ## Release Highlights
 
 ### SQL Filter Expression for Streams
@@ -169,8 +175,6 @@ compared to other versions.
 
 ## Changes Worth Mentioning
 
-This section is **incomplete** and will be expanded as 4.2 approaches its release candidate stage.
-
 ### Core Server
 
 #### Enhancements
@@ -204,8 +208,8 @@ This section is **incomplete** and will be expanded as 4.2 approaches its releas
 
    GitHub issues: [#13783](https://github.com/rabbitmq/rabbitmq-server/discussions/13783), [#14408](https://github.com/rabbitmq/rabbitmq-server/pull/14408)
 
- * Similarly to the number of [queues](https://github.com/rabbitmq/rabbitmq-server/pull/11196) and [virtual hosts](https://github.com/rabbitmq/rabbitmq-server/pull/7798), it is now possible
-   to configure a limit on the cluster-wide number of exchanges that applications
+ * Similarly to the number of [queues](https://github.com/rabbitmq/rabbitmq-server/pull/11196) and [virtual hosts](https://github.com/rabbitmq/rabbitmq-server/pull/7798),
+   it is now possible to configure a limit on the cluster-wide number of exchanges that applications
    can create:
 
    ```ini
@@ -218,6 +222,18 @@ This section is **incomplete** and will be expanded as 4.2 approaches its releas
 
    GitHub issue: [#14546](https://github.com/rabbitmq/rabbitmq-server/pull/14546)
 
+ * It is now possible to disable specific queue types.
+
+   Clients won't be able to declare new queues or streams of the disabled types.
+
+   GitHub issue: [#14624](https://github.com/rabbitmq/rabbitmq-server/pull/14624)
+
+ * Users of 3rd party plugins now can use a dedicated directory that won't be removed
+   during Mnesia to Khepri upgrades. Previously all non-whitelisted directories in the node's data directory
+   would be deleted together with other Mnesia data (Khepri data is stored separately) at the end of such a migration.
+
+   GitHub issue: [#11304](https://github.com/rabbitmq/rabbitmq-server/issues/11304)
+
 #### Bug Fixes
 
  * Classic queues could run into a rare message store exception that resuulted in
@@ -239,6 +255,11 @@ This section is **incomplete** and will be expanded as 4.2 approaches its releas
 
    GitHub issues: [#14202](https://github.com/rabbitmq/rabbitmq-server/issues/14202), [#14458](https://github.com/rabbitmq/rabbitmq-server/pull/14458)
 
+ * Certain periodic quorum queue operations now perform metadata store updates in a more defensive way
+   in a network partition scenario.
+
+   GitHub issue: [#14672](https://github.com/rabbitmq/rabbitmq-server/pull/14672)
+
  * `default_password`, `ssl_options.password` now can tell between a generated random password
    value and an [encrypted value](https://www.rabbitmq.com/docs/configure#configuration-encryption) better.
 
@@ -251,6 +272,14 @@ This section is **incomplete** and will be expanded as 4.2 approaches its releas
 
    GitHub issue: [#14409](https://github.com/rabbitmq/rabbitmq-server/pull/14409)
 
+ * `*.cacerts` (not to be confused with `cacertfile`) settings in `rabbitmq.conf` did not have the expected effect and were removed
+   to eliminate confusion.
+
+   **This is a potentially breaking change**.
+
+   GitHub issue: [#14655](https://github.com/rabbitmq/rabbitmq-server/pull/14655)
+
+
 
 ### Stream Plugin
 
@@ -320,15 +349,27 @@ This section is **incomplete** and will be expanded as 4.2 approaches its releas
 
 #### Bug Fixes
 
+ * Direct AMQP 0-9-1 shovel connections within a cluster (not to be confused with local shovels introduced in this release)
+   are now blocked by [resource alarms]() just like their "network" counterparts are.
+
+   GitHub issue: [#14657](https://github.com/rabbitmq/rabbitmq-server/issues/14657)
+
+ * Shovels could not be deleted using `rabbitmqctl` in some cases.
+
+   GitHub issue: [#14623](https://github.com/rabbitmq/rabbitmq-server/issues/14623)
+
+ * The number of pending messages reported by shovels was not an integer in certain scenarios.
+
+   GitHub issue: [#14710](https://github.com/rabbitmq/rabbitmq-server/pull/14710)
+
  * Prometheus metric collector failed with an exception when the scraper endpoint
    was hit when one or more shovels were still starting.
 
-
 ### AWS Peer Discovery Plugin
 
-####
+#### Bug Fixes
 
- * The plugin implicitly depended on ordering of `` and `` EC2 API response fields,.
+ * The plugin implicitly depended on ordering of `networkInterfaceSet` and `` EC2 API response fields,
    which could result in obscure cluster formation issues.
 
    GitHub issue: [#14557](https://github.com/rabbitmq/rabbitmq-server/pull/14557)
@@ -358,6 +399,7 @@ This section is **incomplete** and will be expanded as 4.2 approaches its releas
  * `osiris` was upgraded to [`1.10.0`](https://github.com/rabbitmq/osiris/releases)
  * `khepri` was upgraded to [`0.17.2`](https://github.com/rabbitmq/khepri/releases)
  * `khepri_mnesia_migration` was upgraded to [`0.8.0`](https://github.com/rabbitmq/khepri_mnesia_migration/releases)
+ * `cowboy` was upgraded to [`2.14.1`](https://github.com/ninenines/cowboy/releases)
  * `cuttlefish` was upgraded to [`3.5.0`](https://github.com/kyorai/cuttlefish/releases)