first connect fails. This is necessary for IPv4+IPv6 and services hosted in redundant data
centers. OkHttp supports modern TLS features (TLS 1.3, ALPN, certificate pinning). It can be
configured to fall back for broad connectivity.

Using OkHttp is easy. Its request/response API is designed with fluent builders and immutability. It

- kubeadm now includes the ability to specify certificate encryption and decryption keys for the upload and download certificate phases as part of the new v1beta2 kubeadm config format. ([#77012](https://github.com/kubernetes/kubernetes/pull/77012), [@rosti](https://github.com/rosti))

      // do not retry.
      if (e.cause is CertificateException) {
        return false
      }
    }
    if (e is SSLPeerUnverifiedException) {
      // e.g. a certificate pinning error.
      return false
    }
    // An example of one we might want to retry with a different route is a problem connecting to a

- The extension API server can now dynamically discover the requestheader CA certificate when the core API server doesn't use certificate based authentication for it's clients. ([#66394](https://github.com/kubernetes/kubernetes/pull/66394), [@rtripat](https://github.com/rtripat))

### SIG Autoscaling

* Allows extension API server to dynamically discover the requestheader CA certificate when the core API server doesn't use certificate based authentication for it's clients ([#66394](https://github.com/kubernetes/kubernetes/pull/66394), [@rtripat](https://github.com/rtripat))

Kubeadm: Automate certificate copy between control planes in HA setups

- Joining control plane nodes to a HA cluster can now be simplified by enabling the optional automatic copy of certificates from an existing control plane node.
- You can now use `kubeadm init --experimental-upload-certs` and `kubeadm join --experimental-control-plane --certificate-key`.

	public final fun check (Ljava/lang/String;[Ljava/security/cert/Certificate;)V
	public fun equals (Ljava/lang/Object;)Z
	public final fun findMatchingPins (Ljava/lang/String;)Ljava/util/List;
	public final fun getPins ()Ljava/util/Set;
	public fun hashCode ()I
	public static final fun pin (Ljava/security/cert/Certificate;)Ljava/lang/String;

    }

    private fun certificatesToString(certificates: Array<X509Certificate>): String {
      val result: MutableList<String> = ArrayList()
      for (certificate in certificates) {
        result.add(certificate.subjectDN.toString() + " " + certificate.serialNumber)
      }
      return result.toString()
    }
  }

  /**

- Kubeadm: add support for certificate chain validation. When using kubeadm in external CA mode, this allows an intermediate CA to be used to sign the certificates. The intermediate CA certificate must be appended to each signed certificate for this to work correctly. ([#97266](https://github.com/kubernetes/kubernetes/pull/97266), [@robbiemcmichael](https://github.com/robbiemcmichael))...

  - `status.conditions` may not contain duplicate types
  - `status.conditions[*].status` is now required
  - `status.certificate` must be PEM-encoded, and contain only CERTIFICATE blocks ([#91685](https://github.com/kubernetes/kubernetes/pull/91685), [@liggitt](https://github.com/liggitt)) [SIG API Machinery, Architecture, Auth, CLI and Testing]