- Kubeadm: add a upgrade health check that deploys a Job ([#81319](https://github.com/kubernetes/kubernetes/pull/81319), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]
- Kubeadm: add the experimental feature gate PublicKeysECDSA that can be used to create a

* Stackdriver cluster logging now deploys a new component to export Kubernetes events. ([#46700](https://github.com/kubernetes/kubernetes/pull/46700), [@crassirostris](https://github.com/crassirostris))

incorrectly placed a pod in the "unschedulable" queue instead of the "backoff" queue. This happened when some plugin previously declared the pod as "unschedulable" and then in a later attempt encounters some other error. Scheduling of that pod then got delayed by up to five minutes, after which periodic flushing moved the pod back into the "active" queue. ([#120334](https://github.com/kubernetes/kubernetes/pull/120334), [@pohly](https://github.com/pohly)) [SIG Scheduling]

### Other (Cleanup...

- Introduce `node.kubernetes.io/exclude-balancer` and `node.kubernetes.io/exclude-disruption` labels in alpha to prevent cluster deployers from being dependent on the optional `node-role` labels which not all clusters may provide. ([#80238](https://github.com/kubernetes/kubernetes/pull/80238), [@smarterclayton](https://github.com/smarterclayton))

incorrectly placed a pod in the "unschedulable" queue instead of the "backoff" queue. This happened when some plugin previously declared the pod as "unschedulable" and then in a later attempt encounters some other error. Scheduling of that pod then got delayed by up to five minutes, after which periodic flushing moved the pod back into the "active" queue. ([#120334](https://github.com/kubernetes/kubernetes/pull/120334), [@pohly](https://github.com/pohly)) [SIG Scheduling]

### Other (Cleanup...

features and stability work required for bootstrapping production clusters efficiently. kubeadm has promoted high availability (HA) capability to beta, allowing users to use the familiar `kubeadm init` and `kubeadm join` commands to [configure and deploy an HA control plane](https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/high-availability/). An entire new test suite has been created specifically for ensuring these features will stay stable over time.

Certificate...

* Make CoreDNS be the default DNS server in kube-up (instead of kube-dns formerly).  ([#67569](https://github.com/kubernetes/kubernetes/pull/67569), [@fturib](https://github.com/fturib))
    * It is still possible to deploy kube-dns by setting CLUSTER_DNS_CORE_DNS=false.
* Added support to restore a volume from a volume snapshot data source.  ([#67087](https://github.com/kubernetes/kubernetes/pull/67087), [@xing-yang](https://github.com/xing-yang))

incorrectly placed a pod in the "unschedulable" queue instead of the "backoff" queue. This happened when some plugin previously declared the pod as "unschedulable" and then in a later attempt encounters some other error. Scheduling of that pod then got delayed by up to five minutes, after which periodic flushing moved the pod back into the "active" queue. ([#120334](https://github.com/kubernetes/kubernetes/pull/120334), [@pohly](https://github.com/pohly)) [SIG Scheduling]

### Other (Cleanup or...

### Deprecation

- Added support for vSphere in-tree volumes migration to vSphere CSI driver. The in-tree vSphere Volume plugin will be deprecated and removed in a future release.