- [alpha] Simplifies bootstrapping of TLS secured communication between the API server and kubelet. ([docs](http://kubernetes.io/docs/admin/master-node-communication/#kubelet-tls-bootstrap)) ([kubernetes/features#43](https://github.com/kubernetes/enhancements/issues/43))

    assertFailsWith<UnknownServiceException> {
      client.newCall(request).execute()
    }.also { expected ->
      assertThat(expected.message).isEqualTo(
        "CLEARTEXT communication not enabled for client",
      )
    }
  }

  @Test
  fun httpsCallsFailWhenProtocolIsH2PriorKnowledge() {
    client =
      client
        .newBuilder()

* The apiserver can now select which type of kubelet-reported address to use for apiserver->node communications, using the --kubelet-preferred-address-types flag. ([#35497](https://github.com/kubernetes/kubernetes/pull/35497), [@liggitt](https://github.com/liggitt))