- 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

- JWT authenticator config set via the --authentication-config flag is now dynamically reloaded as the file changes on disk. ([#123525](https://github.com/kubernetes/kubernetes/pull/123525), [@enj](https://github.com/enj)) [SIG API Machinery, Auth and Testing]

- Add flag --lease-max-object-size and metric etcd_lease_object_counts for kube-apiserver to config and observe max objects attached to a single etcd lease. ([#97480](https://github.com/kubernetes/kubernetes/pull/97480), [@lingsamuel](https://github.com/lingsamuel)) [SIG API Machinery, Instrumentation and Scalability]

kubeadm-config Before:

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

- `kubeadm`: added a new "kubeadm config validate" command that can be used to
  validate any input config file. Use the `--config` flag to pass a config file
  to it. See the command `--help` screen for more information. As a result of adding
  this new command, enhance the validation capabilities of the existing "kubeadm

le]._config;else{if(null==(t=_a(a.parentLocale)))return ra[a.parentLocale]||(ra[a.parentLocale]=[]),ra[a.parentLocale].push({name:e,config:a}),null;s=t._config}return na[e]=new S(b(s,a)),ra[e]&&ra[e].forEach(function(e){ma(e.name,e.config)}),oa(e),na[e]}function ua(e){var a;if(e&&e._locale&&e._locale._abbr&&(e=e._locale._abbr),!e)return ta;if(!i(e)){if(a=_a(e))return a;e=[e]}return ia(e)}function la(e){var a,t=e._a;return t&&-2===L(e).overflow&&(a=t[pe]<0||11<t[pe]?pe:t[ke]<1||t[ke]>Se(t[fe],t[p...

- kubelet: the `--image-credential-provider-config` file was loaded with strict deserialization, which failed if the config file contained duplicate or unknown fields. This protected against accidentally running with malformed config files, unindented files, or typos in field names, and it...

### Bug or Regression

- Bump system-validators to v1.9.2: remove version-specific cgroup kernel config checks to avoid false failures on cgroup v2 systems when v1-only configs are missing. ([#134086](https://github.com/kubernetes/kubernetes/pull/134086), [@pacoxu](https://github.com/pacoxu)) [SIG Cluster Lifecycle]

- Promoted the `APIServerTracing` feature gate to GA. The `--tracing-config-file` flag accepted `TracingConfiguration` in version `apiserver.config.k8s.io/v1` (with no changes from `apiserver.config.k8s.io/v1beta1`). ([#132340](https://github.com/kubernetes/kubernetes/pull/132340), [@dashpole](https://github.com/dashpole)) [SIG API Machinery and Testing]