// user of Trailers in the wild: gRPC (using them only over http2),
// and gRPC libraries permit setting trailers mid-stream without
// predeclaring them. So: change of plans. We still permit the old
// way, but we also permit this hack: if a Header() key begins with
// "Trailer:", the suffix of that key is a Trailer. Because ':' is an

It could be used to tell kubeadm to wait for all control plane components to be ready when running "kubeadm init" or "kubeadm join --control-plane". Previously, kubeadm only waited for the kube-apiserver. The "kubeadm join" workflow now includes a new experimental phase called "wait-control-plane". This phase was marked as non-experimental when WaitForAllControlPlaneComponents became GA. Accordingly, a "kubeadm init" phase "wait-control-plane" was also available once WaitForAllControlPlaneComponents...

release.  A new alpha feature is introduced to improve the mechanism that nodes heartbeat back to the control plane.  The `NodeLease` feature results in the node using a `Lease` resource in the `kube-node-lease` namespace that is renewed periodically.  The `NodeStatus` that was used previously to heartbeat back to the control plane is only updated when it changes.  This reduces load on the control plane for large clusters. The Kubelet plugin registration mechanism, which enables automatic discovery of external...

(N-3). This aligns with the recent change made by SIG Architecture that extends the support skew between the control plane and kubelets. Tolerate this new kubelet skew for the commands `init`, `join` and `upgrade`. Note that if the `kubeadm` user applies a control plane version that is older than the `kubeadm` version (N-1 maximum) then the skew between the kubelet and control plane would become a maximum of N-2. ([#120825](https://github.com/kubernetes/kubernetes/pull/120825), [@pacoxu](https://github.com/pacoxu))...

  - The `kubeadm upgrade node config` and `kubeadm upgrade node experimental-control-plane` commands are deprecated in favor of `kubeadm upgrade node`, and will be removed in a future release. ([#78408](https://github.com/kubernetes/kubernetes/pull/78408), [@fabriziopandini](https://github.com/fabriziopandini))

### Deploy a more secure control plane with kubeadm

A new alpha feature allows running the kubeadm control plane components as non-root users. This is a long requested security measure in kubeadm. To try it you must enable the kubeadm-specific `RootlessControlPlane` feature gate. When you deploy a cluster using this alpha feature, your control plane runs with lower privileges.

  - Please adapt your tooling built on top of kubeadm to use the "node-role.kubernetes.io/control-plane" label.
  - The taint applied to control-plane nodes "node-role.kubernetes.io/master:NoSchedule" is now deprecated and will be removed in a future release after a GA deprecation period.

- Kubeadm: only taint control plane nodes when the legacy "master" taint is present. This avoids the bug where "kubeadm upgrade" will re-taint a control plane  node with the new "control plane" taint even if the user explicitly untainted the node. ([#109840](https://github.com/kubernetes/kubernetes/pull/109840), [@neolit123](https://github.com/neolit123))

type GlobalLoggingConfig struct {
	state         protoimpl.MessageState
	sizeCache     protoimpl.SizeCache
	unknownFields protoimpl.UnknownFields

	// Comma-separated minimum per-scope logging level of messages to output, in the form of <scope>:<level>,<scope>:<level>

- Kubeadm: only taint control plane nodes when the legacy "master" taint is present. This avoids a bug where "kubeadm upgrade" will re-taint a control plane node with the new "control plane" taint even if the user explicitly untainted the node. ([#109841](https://github.com/kubernetes/kubernetes/pull/109841), [@neolit123](https://github.com/neolit123)) [SIG Cluster...