* genericapiserver: cut off certificates api dependency ([#39947](https://github.com/kubernetes/kubernetes/pull/39947), [@sttts](https://github.com/sttts))
* genericapiserver: extract CA cert from server cert and SNI cert chains ([#39022](https://github.com/kubernetes/kubernetes/pull/39022), [@sttts](https://github.com/sttts))

  private @Nullable Object[] requireValues() {
    return requireNonNull(values);
  }

  /*
   * The following methods are safe to call as long as the conditions in the *previous* comment are
   * met *and* the index is less than size().
   *
   * (The above explains when these methods are safe from a `nullness` perspective. From an
   * `unchecked` perspective, they're safe because we put only K/V elements into each array.)

			objectModTime:   time.Now().UTC().Add(-10 * 24 * time.Hour), // Created 10 days ago
			hasManyVersions: true,
			expectedAction:  DeleteAllVersionsAction,
		},
		// TransitionAction applies since object doesn't meet the age criteria for DeleteAllVersions
		{

equality-based selector in 1.1).
  * Running against a secured etcd requires these flags to be passed to
kube-apiserver (instead of --etcd-config):
     * --etcd-certfile, --etcd-keyfile (if using client cert auth)
     * --etcd-cafile (if not using system roots)
  * As part of preparation in 1.2 for adding support for protocol buffers (and the
direct YAML support in the API available today), the Content-Type and Accept

* kubeadm: add back `--cert-dir` option for `kubeadm init phase certs sa` ([#73239](https://github.com/kubernetes/kubernetes/pull/73239), [@mattkelly](https://github.com/mattkelly))

pull/57902), [@kawych](https://github.com/kawych))

* On cluster provision or upgrade, kubeadm now generates certs and secures all connections to the etcd static-pod with mTLS. This includes the etcd serving cert, the etcd peer cert, and the apiserver etcd client cert. Flags and hostMounts are added to the etcd and apiserver static-pods to load these certs. For connections to etcd, https is now used in favor of http. ([#57415](https://github.com/kubernetes/kubernetes/pull/57415), [@s...

certificates directory as `kubelet-client.key` and `kubelet-client.crt`.  Subsequent certificates created by cert rotation were created in a combined PEM file that was atomically rotated as `kubelet-client-DATE.pem` in that directory, which meant clients relying on the `node.kubeconfig` generated by bootstrapping would never use a rotated cert.  The initial bootstrap certificate is now generated into the cert directory as a PEM file and symlinked to `kubelet-client-current.pem` so that the generated kubeconfig...

	// Initializing sub-systems needs a retry mechanism for
	// the following reasons:
	//  - Read quorum is lost just after the initialization
	//    of the object layer.
	//  - Write quorum not met when upgrading configuration
	//    version is needed, migration is needed etc.
	rquorum := InsufficientReadQuorum{}
	wquorum := InsufficientWriteQuorum{}

	// One of these retriable errors shall be retried.

the Duck:  `it's generally a frog or a worm.  The question is,
what did the archbishop find?'

  The Mouse did not notice this question, but hurriedly went on,
`"--found it advisable to go with Edgar Atheling to meet William
and offer him the crown.  William's conduct at first was
moderate.  But the insolence of his Normans--"  How are you
getting on now, my dear?' it continued, turning to Alice as it
spoke.

- The CSR signing cert/key pairs will be reloaded from disk like the kube-apiserver cert/key pairs ([#86816](https://github.com/kubernetes/kubernetes/pull/86816), [@deads2k](https://github.com/deads2k)) [SIG API Machinery, Apps and Auth]