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...

- Show a warning message to inform users that the `legacy` profile is planned to be deprecated. ([#127230](https://github.com/kubernetes/kubernetes/pull/127230), [@mochizuki875](https://github.com/mochizuki875)) [SIG CLI]

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...

- 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))

  - 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))

  * Verification against Kubernetes 1.8 is planned soon after the release.

* [stable] [frakti](https://github.com/kubernetes/frakti): CRI implementation for hypervisor-based runtimes is now v1.1. [[@feiskyer](https://github.com/feiskyer)]

  * Enhance CNI plugin compatibility, supports flannel, calico, weave and so on.

Additionally, since the information returned from the discovery APIs may change dynamically, a cache of the results should not be considered authoritative.
ETag support is planned in a future version to facilitate client caching.
([#47977](https://github.com/kubernetes/kubernetes/pull/47977), [#44957](https://github.com/kubernetes/kubernetes/pull/44957))

(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))...

- Restores priority of static control plane pods in the cluster/gce/manifests control-plane manifests ([#89970](https://github.com/kubernetes/kubernetes/pull/89970), [@liggitt](https://github.com/liggitt)) [SIG Cluster Lifecycle and Node]

### Other (Cleanup or Flake)

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`.