RabbitMQ `3.9.22` is a maintenance release in the `3.9.x` release series.
Please refer to the **Upgrading to 3.9** section from [v3.9.0 release notes](https://github.com/rabbitmq/rabbitmq-server/releases/tag/v3.9.0) if upgrading from a version prior to 3.9.0.
This release requires at least Erlang 24.x, and supports Erlang 25. [RabbitMQ and Erlang/OTP Compatibility Matrix](https://www.rabbitmq.com/which-erlang.html) has more details on Erlang version requirements for RabbitMQ.
## Changes Worth Mentioning
Release notes can be found on GitHub at [rabbitmq-server/release-notes](https://github.com/rabbitmq/rabbitmq-server/tree/v3.10.x/release-notes).
### Core Server
#### Enhancements
* In environments where DNS resolution is not yet available at the time RabbitMQ nodes boot and try to perform [peer discovery](https://www.rabbitmq.com/cluster-formation.html),
such as CoreDNS with default caching interval of 30s on Kubernetes, nodes now will retry
hostname resolution (including of their own host) several times with a wait interval.
The recommended solution is to [decrease CoreDNS caching interval](https://kubernetes.io/docs/concepts/workloads/controllers/statefulset/#stable-network-id).
