- Kubeadm: enhanced the "patches" functionality to be able to patch kubelet config files containing `v1beta1.KubeletConfiguration`. The new patch target is called `kubeletconfiguration` (e.g. patch file `kubeletconfiguration+json.json`).This makes it possible to apply node specific KubeletConfiguration options during `init`, `join` and `upgrade`, while the main `KubeletConfiguration` that is passed to `init` as part of the `--config` file can still act as the global stored in the cluster `KubeletConfiguration`....

- 'kubeadm: Stopped storing the ResolverConfig in the global KubeletConfiguration
  and sets it dynamically for each node instead.' ([#124038](https://github.com/kubernetes/kubernetes/pull/124038), [@SataQiu](https://github.com/SataQiu))
- 'kubeadm: fixed a regression where the KubeletConfiguration is not properly
  downloaded during "kubeadm upgrade" command from the kube-system/kubelet-config

- Kubeadm: add the kubeadm specific, Alpha (disabled by default) feature gate UnversionedKubeletConfigMap. When this feature is enabled kubeadm will start using a new naming format for the ConfigMap where it stores the KubeletConfiguration structure. The old format included the Kubernetes version - "kube-system/kubelet-config-1.22", while the new format does not - "kube-system/kubelet-config". A similar formatting change is done for the related RBAC rules. The old format is now...

*   The Kubelet's feature gates are now specified as a map when provided via a JSON or YAML KubeletConfiguration, rather than as a string of key-value pairs, making them less awkward for...

* 'none' can now be specified in KubeletConfiguration.EnforceNodeAllocatable (--enforce-node-allocatable) to explicitly disable enforcement. ([#59515](https://github.com/kubernetes/kubernetes/pull/59515), [@mtaufen](https://github.com/mtaufen))

- Kubeadm: fixed a bug on 'kubeadm join' where using patches with a kubeletconfiguration target was not respected when performing the local kubelet healthz check. ([#126251](https://github.com/kubernetes/kubernetes/pull/126251), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]

warnings for fields with incorrect case sensitivity - e.g. `controlPlaneEndpoint` (valid), `ControlPlaneEndpoint` (invalid). Instead of only printing warnings during `init` and `join` also print warnings when downloading the ClusterConfiguration, KubeletConfiguration or KubeProxyConfiguration objects from the cluster. This can be useful if the user has patched these objects in their respective ConfigMaps with mistakes. ([#107725](https://github.com/kubernetes/kubernetes/pull/107725), [@neolit123](https...

  - `v1alpha1` has been removed.
  - `v1alpha3` has split apart `MasterConfiguration` into separate components; `InitConfiguration`, `ClusterConfiguration`, `JoinConfiguration`, `KubeletConfiguration`, and `KubeProxyConfiguration`
  - Different configuration types can be supplied all in the same file separated by `---`.
- Improved CRI handling
  - crictl is no longer required in docker-only setups.

deadline seconds max allowed value to be maximum uint32 to avoid overflow ([#46640](https://github.com/kubernetes/kubernetes/pull/46640), [@derekwaynecarr](https://github.com/derekwaynecarr))

  * Fix a bug with cAdvisorPort in the KubeletConfiguration that prevented setting it to 0, which is in fact a valid option, as noted in issue [#11710](https://github.com/kubernetes/kubernetes/pull/11710). ([#46876](https://github.com/kubernetes/kubernetes/pull/46876), [@mtaufen](https://github.com/mtaufen))...

 - Kubeadm: during "init" an empty cgroupDriver value in the KubeletConfiguration is now always set to "systemd" unless the user is explicit about it. This requires existing machine setups to configure the container runtime to use the "systemd" driver. Documentation on this topic can be found here: https://kubernetes.io...