* Adds optional group and version information to the discovery interface, so that if an endpoint uses non-default values, the proper value of "kind" can be determined. Scale is a common example. ([#49971](https://github.com/kubernetes/kubernetes/pull/49971), [@deads2k](https://github.com/deads2k))

- Kubeadm: during execution of the "check expiration" command, treat the etcd CA as external if there is a missing etcd CA key file (etcd/ca.key) and perform the proper validation on certificates signed by the etcd CA. Additionally, make sure that the CA for all entries in the output table is included - for both certificates on disk and in kubeconfig files. ([#106924](https://github.com/kubernetes/kubernetes/pull/106924),...

ensure static pods (especially those that use fixed UIDs) are restarted.  As a side effect of these changes static pods will be restarted with lower latency than before (2s vs 4s, on average) and rapid updates to pod configuration should take effect sooner.
  
  A new metric `kubelet_known_pods` has been added at ALPHA stability to report the number of pods a Kubelet is tracking in a number of internal states.  Operators may use the metrics to track an excess of pods in the orphaned state...

* Adds optional group and version information to the discovery interface, so that if an endpoint uses non-default values, the proper value of "kind" can be determined. Scale is a common example. ([#49971](https://github.com/kubernetes/kubernetes/pull/49971), [@deads2k](https://github.com/deads2k))

    * kubeadm - Ensure that the etcd certificates are generated using a proper CN
    * kubeadm - Update generated etcd peer certificate to include localhost addresses for the default configuration.
    * kubeadm - Increase the manifest update timeout to make upgrades a bit more reliable.

this is known to affect is curl when you use -d with JSON but don't set a
content type, helpfully sends "application/x-www-urlencoded", which is not
correct.
Other client authors should double check that you are sending proper
accept and content type headers, or set no value (in which case JSON is the
default).
An example using curl:
<code>curl -H "Content-Type: application/json" -XPOST -d

- Fixed the calculation of the requeue time in the cronjob controller, resulting in proper handling of failed/stuck jobs. ([#121327](https://github.com/kubernetes/kubernetes/pull/121327), [@soltysh](https://github.com/soltysh))

* the resource quota controller was not adding quota to be resynced at proper interval ([#45685](https://github.com/kubernetes/kubernetes/pull/45685), [@derekwaynecarr](https://github.com/derekwaynecarr))

* Limit the number of names per image reported in the node status ([#32914](https://github.com/kubernetes/kubernetes/pull/32914), [@yujuhong](https://github.com/yujuhong))
* Fixes in HPA: consider only running pods; proper denominator in avg request calculations. ([#33735](https://github.com/kubernetes/kubernetes/pull/33735), [@jszczepkowski](https://github.com/jszczepkowski))

unschedulable pods, scale up is required and cloud provider is slow to set up networking for new nodes.
Anyway, the cluster should get back to the proper size after 10 min.

### Deployment