### Cluster Lifecycle

* kubeadm: preflight checks on external etcd certificates are now skipped when joining a control-plane node with automatic copy of cluster certificates (--certificate-key) ([#75847](https://github.com/kubernetes/kubernetes/pull/75847), [@fabriziopandini](https://github.com/fabriziopandini))

	}

	cert, ok := clientKey.(*ssh.Certificate)
	if !ok {
		return errSftpPublicKeyWithoutCert
	}

	// ssh.CheckCert called by ssh.Authenticate accepts certificates
	// with empty principles list so we block those in here.
	if len(cert.ValidPrincipals) == 0 {
		return errSftpCertWithoutPrincipals
	}

	// Verify that certificate provided by user is issued by trusted CA,

* [beta] Kubelet certificate rotation through the certificates API has been promoted from alpha to beta. RBAC cluster roles for the certificates controller have been added for common uses of the certificates API, such as the kubelet's.

if ! [ -d ~/.aws ]; then
	mkdir -p ~/.aws
fi
cat >~/.aws/credentials <<EOF
[enterprise]
region = us-east-1
aws_access_key_id = minio
aws_secret_access_key = minio123
EOF

# Create certificates for TLS enabled MinIO
echo -n "Setup certs for MinIO instances ..."
wget -O certgen https://github.com/minio/certgen/releases/latest/download/certgen-linux-amd64 && chmod +x certgen
./certgen --host localhost

}

cleanup

export MINIO_CI_CD=1
export MINIO_BROWSER=off
export MINIO_ROOT_USER="minio"
export MINIO_ROOT_PASSWORD="minio123"
TEST_MINIO_ENC_KEY="MDEyMzQ1Njc4OTAxMjM0NTY3ODkwMTIzNDU2Nzg5MDA"

# Create certificates for TLS enabled MinIO
echo -n "Setup certs for MinIO instances ..."
wget -O certgen https://github.com/minio/certgen/releases/latest/download/certgen-linux-amd64 && chmod +x certgen
./certgen --host localhost

previously created the first bootstrap client credentials in the 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...

  - [WARNING: etcd backup strongly recommended](#warning-etcd-backup-strongly-recommended)
  - [Major updates and release themes](#major-updates-and-release-themes)
  - [Action Required](#action-required-1)
    - [Certificates API](#certificates-api)
    - [Cluster Autoscaler](#cluster-autoscaler)
    - [Deployment](#deployment)
    - [Federation](#federation)
    - [Internal Storage Layer](#internal-storage-layer)

 *  Fix: Don't silently ignore calls to `EventSource.cancel()` made from
    `EventSourceListener.onOpen()`.
 *  Fix: Enforce the max intermediates constraint when using pinned certificates with Conscrypt.
    This impacts Conscrypt when the server's presented certificates form both a trusted-but-unpinned
    chain and an untrusted-but-pinned chain.
 *  Upgrade: [Kotlin 1.6.10][kotlin_1_6_10].


## Version 5.0.0-alpha.3

_2021-11-22_

    val certificate: X509Certificate = heldCertificate.certificate
    val certificatePinner: CertificatePinner = CertificatePinner.Builder().build()
    val certificates: List<Certificate> = listOf()
    certificatePinner.check("", listOf(certificate))
    certificatePinner.check("", arrayOf<Certificate>(certificate, certificate).toList())
    val pin: String = CertificatePinner.pin(certificate)