- Fixed a bug that occurred when the hostname label of a node did not match the node name, pods bound to a PersistentVolume with `nodeAffinity` using the hostname may be scheduled to the wrong node or experience scheduling failures. ([#125398](https://github.com/kubernetes/kubernetes/pull/125398), [@AxeZhan](https://github.com/AxeZhan)) [SIG Scheduling...

    - [<code>kubectl debug</code> graduates to Beta](#kubectl-debug-graduates-to-beta)
    - [Removing deprecated flags in kubeadm](#removing-deprecated-flags-in-kubeadm)
    - [Pod Hostname as FQDN graduates to Beta](#pod-hostname-as-fqdn-graduates-to-beta)
    - [<code>TokenRequest</code> / <code>TokenRequestProjection</code> graduates to General Availability](#tokenrequest--tokenrequestprojection-graduates-to-general-availability)

* kube-proxy needs to be configured to override hostname in some environments. ([#857](https://github.com/kubernetes/kubeadm/issues/857), [@detiber](https://github.com/detiber))

* Port-forward: use out and error streams instead of glog ([#17030](https://github.com/kubernetes/kubernetes/pull/17030), [@csrwng](https://github.com/csrwng))
* Promote Pod Hostname & Subdomain to fields (were annotations) ([#24362](https://github.com/kubernetes/kubernetes/pull/24362), [@ArtfulCoder](https://github.com/ArtfulCoder))

    val sink = GzipSink(result).buffer()
    sink.writeUtf8(data)
    sink.close()
    return result
  }

  companion object {
    private val NULL_HOSTNAME_VERIFIER = HostnameVerifier { hostname, session -> true }
  }

- `StatefulSet` names must be DNS labels, rather than subdomains. Any `StatefulSet`
  which took advantage of subdomain validation (by having dots in the name) can't
  possibly have worked, because we eventually set `pod.spec.hostname` from the `StatefulSetName`,
  and that is validated as a DNS label. ([#114172](https://github.com/kubernetes/kubernetes/pull/114172), [@thockin](https://github.com/thockin))

- Kubeadm: Fixed a preflight check that could fail hostname construction in IPv6 setups. ([#134588](https://github.com/kubernetes/kubernetes/pull/134588), [@liggitt](https://github.com/liggitt)) [SIG API Machinery, Auth, Cloud Provider, Cluster Lifecycle and Testing]

  qualified domain name (FQDN) of a Pod is set as hostname of its containers. 
  In Linux containers, this means setting the FQDN in the hostname field of the 
  kernel (the nodename field of struct utsname).  In Windows containers, this
  means setting the this means setting the registry value of hostname for the registry key HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Services\\Tcpip\\Parameters to FQDN. 

			default:
			}
		}
		// validate replication ARN against target endpoint
		selfTarget, _ := isLocalHost(clnt.EndpointURL().Hostname(), clnt.EndpointURL().Port(), globalMinioPort)
		if !sameTarget {
			sameTarget = selfTarget
		}
	}

	if len(arns) == 0 {
		return false, toAPIError(ctx, BucketRemoteTargetNotFound{Bucket: bucket})
	}

* Webhook client credentials configured with `--admission-control-config-file` must include non-default ports in the configured hostnames. For example, a webhook configured to speak to port 8443 on service `mysvc` in namespace `myns` would specify client credentials in a stanza with `name: mysvc.myns.svc:8443`. See https://kubernetes.io/docs/reference/access-authn-authz/extensible...