* kube-apiserver: The `AdmissionConfiguration` type accepted by `--admission-control-config-file` has been promoted to `apiserver.config.k8s.io/v1` with no schema changes. ([#85098](https...

*   The API group/version for the kube-proxy configuration has changed from `componentconfig/v1alpha1` to `kubeproxy.config.k8s.io/v1alpha1`. If you are using a config file for kube-proxy instead of the command line flags, you must change its apiVersion to `kubeproxy.config.k8s.io/v1alpha1`. ([#53645](https://github.com/kubernetes/kubernetes/pull/53645), [@xiangpengzhao](https://github.com/xiangpengzhao))

- '`kube-apiserver`: adds `--authentication-config` flag for reading `AuthenticationConfiguration`
  files. `--authentication-config` flag is mutually exclusive with the existing `--oidc-*`
  flags.' ([#119142](https://github.com/kubernetes/kubernetes/pull/119142), [@aramase](https://github.com/aramase))
- '`kube-scheduler` component config (`KubeSchedulerConfiguration`) `kubescheduler.config.k8s.io/v1beta3`

- Introduce api-extensions category which will return: mutating admission configs, validating admission configs, CRDs and APIServices when used in kubectl get, for example. ([#95603](https://github.com/kubernetes/kubernetes/pull/95603), [@soltysh](https://github.com/soltysh)) [SIG API Machinery]

- Kubeadm:  'kubeadm alpha kubelet config download' has been removed, please use 'kubeadm upgrade node phase kubelet-config' instead ([#87944](https://github.com/kubernetes/kubernetes/pull/87944), [@SataQiu](https://github.com/SataQiu)) [SIG Cluster Lifecycle]

   * -viper-config can be used to set also the options defined by command line flags
   * the default config file is "e2e.yaml/toml/json/..." and the test starts when no such config is found (as before) but if -viper-config is used, the config file must exist
   * -viper-config can be used to select a file with full path, with or without file suffix

* kubeadm: remove deprecated kubeadm config print-defaults command ([#71467](https://github.com/kuberne...

kubeadm-config Before:

```
apiVersion: v1
kind: ConfigMap
metadata:
  name: kubeadm-config
data:
  MasterConfiguration: |
    kubeProxy:
      config:
        featureGates: "SupportIPVSProxyMode=true"
```

  * No longer updates the last-applied-configuration annotation when --save-config is unspecified or false. ([#41924](https://github.com/kubernetes/kubernetes/pull/41924), [@ymqytw](https://github.com/ymqytw))
  * Fixes issue that caused apply to revert changes made by edit

#### Bug fixes

- kubeadm: Default component configs are now printable via kubeadm config print-default ([#66074](https://github.com/kubernetes/kubernetes/pull/66074), [@rosti](https://github.com/rosti)) Courtesy of SIG Cluster Lifecycle