- Kubeadm: added the experimental (alpha) feature gate `EtcdLearnerMode` that allows etcd members to be joined as learner and only then promoted as voting members ([#113318](https://github.com/kubernetes/kubernetes/pull/113318), [@pacoxu](https://github.com/pacoxu))

Features for this release were tracked via the use of the [kubernetes/features](https://github.com/kubernetes/features) issues repo. Each Feature issue is owned by a Special Interest Group from [kubernetes/community](https://github.com/kubernetes/community)

## Kubefed

assignment of regular parameters.
</p>

<pre>
func Split(s string, pos int) (string, string) {
	return s[0:pos], s[pos:]
}

func Join(s, t string) string {
	return s + t
}

if Join(Split(value, len(value)/2)) != value {
	log.Panic("test fails")
}
</pre>

<p>
A method call <code>x.m()</code> is valid if the <a href="#Method_sets">method set</a>

flag `--experimental-patches` is now deprecated and will be removed in a future release. You can migrate to using the new flag `--patches`. Add a new field `{Init|Join}Configuration.patches.directory` that can be used for the same purpose. For `init` and `join` it is now recommended that you migrate to configure patches via `{Init|Join}Configuration.patches.directory`. For the time being, these flags can be mixed with `--config`, but that might change in the future. On a command line, the last *patches...

- kubeadm: Improved resiliency when it comes to updating the `kubeadm-config` configmap upon new control plane joins or resets. This allows for safe multiple control plane joins and/or resets. ([#76821](https://github.com/kubernetes/kubernetes/pull/76821), [@ereslibre](https://github.com/ereslibre))

### Juju
* The kubernetes-master, kubernetes-worker and kubeapi-load-balancer charms have gained an nrpe-external-master relation, allowing the integration of their monitoring in an external Nagios server. ([#41923](https://github.com/kubernetes/kubernetes/pull/41923), [@Cynerva](https://github.com/Cynerva))

- HA improvements:
  - `kubeadm join --experimental-control-plane` can now be used to join control plane instances to an existing cluster.
  - `kubeadm upgrade node experimental-control-plane` can now be used for upgrading secondary control plane instances created with `kubeadm join --experimental-control-plane`.
Multi-arch support (EXPERIMENTAL):

### (No, really, you MUST read this before you upgrade)

- Kubeadm: remove the deprecated flag `--experimental-patches` for the `init|join|upgrade` commands. The flag `--patches` is no longer allowed in a mixture with the flag `--config`. Please use the kubeadm configuration for setting patches for a node using `{Init|Join}Configuration.patches`. ([#104065](https://github.com/kubernetes/kubernetes/pull/104065), [@pacoxu](https://github.com/pacoxu))

- Kubeadm: added `show-join-command` as a new separate phase at the end of `kubeadm init`. You can skip printing the join information by using `kubeadm init --skip-phases=show-join-command`. Executing only this phase on demand will throw an error because the phase needs dependencies such as bootstrap tokens to be pre-populated. ([#111512](https://git...

- Kubeadm: fix the bug that configurable KubernetesVersion not respected during kubeadm join ([#111021](https://github.com/kubernetes/kubernetes/pull/111021), [@SataQiu](https://github.com/SataQiu)) [SIG Cluster Lifecycle]

## Dependencies

### Added
_Nothing has changed._

### Changed