- Promoted `RelaxedDNSSearchValidation` to beta, allowing for Pod search domains to be a single dot "." or contain an underscore "_". ([#130128](https://github.com/kubernetes/kubernetes/pull/130128), [@adrianmoisey](https://github.com/adrianmoisey)) [SIG Apps and Network]

- Graduated relaxed DNS search string validation to GA. For the Pod API, `.spec.dnsConfig.searches`
  now allows an underscore (`_`) where a dash (`-`) would be allowed, and it allows search strings be a single dot `.`. ([#132036](https://github.com/kubernetes/kubernetes/pull/132036), [@adrianmoisey](https://github.com/adrianmoisey)) [SIG Network and Testing]

- Allow for Pod search domains to be a single dot `.` or contain an underscore `_` ([#127167](https://github.com/kubernetes/kubernetes/pull/127167), [@adrianmoisey](https://github.com/adrianmoisey)) [SIG Apps, Network and Testing]

- Fixed a bug which kubectl would emit duplicate warning messages for flag names that contain an underscore and recommend using a nonexistent flag in some cases. ([#103852](https://github.com/kubernetes/kubernetes/pull/103852), [@brianpursley](https://github.com/brianpursley))

* Block device support has been added for azure disk. ([#63841](https://github.com/kubernetes/kubernetes/pull/63841), [@andyzhangx](https://github.com/andyzhangx))
* Azure VM names can now contain the underscore (`_`) character ([#63526](https://github.com/kubernetes/kubernetes/pull/63526), [@djsly](https://github.com/djsly))
* Azure disks now support external resource groups.

* Using `kubectl describe` on CRDs that use underscores will be prettier. ([#65391](https://github.com/kubernetes/kubernetes/pull/65391), [@smarterclayton](https://github.com/smarterclayton))