- Kubeadm: allow the "certs check-expiration" command to not require the existence of the cluster CA key (ca.key file) when checking the expiration of managed certificates in kubeconfig files. ([#106927](https://github.com/kubernetes/kubernetes/pull/106927), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]

- Kubeadm: Added support during the preflight check "CreateJob" of "kubeadm upgrade" to check if there are no nodes where a Pod can be scheduled. If there are none, show a warning and skip this preflight check. This can happen in single node clusters where the only node was drained. ([#124503](https://github.com/kubernetes/kubernetes/pull/124503), [@neolit123](https://github.com/neolit123))...

- Added authorization check support to the CEL expressions of ValidatingAdmissionPolicy via a `authorizer`

winkernel mode. `--forward-healthcheck-vip`, if specified as true, health check traffic whose destination is service VIP will be forwarded to kube-proxy's healthcheck service. `--root-hnsendpoint-name` specifies the name of the hns endpoint for the root network namespace. This option enables the pass-through load balancers like Google's GCLB to correctly health check the backend services. Without this change, the health check packets is dropped, and Windows node will be considered to be unhealthy by...

### Bug or Regression

- Kubeadm: allow the "certs check-expiration" command to not require the existence of the cluster CA key (ca.key file) when checking the expiration of managed certificates in kubeconfig files. ([#106931](https://github.com/kubernetes/kubernetes/pull/106931), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]

- Kubeadm: during the preflight check "CreateJob" of "kubeadm upgrade", check if there are no nodes where a Pod can schedule. If there are none, show a warning and skip this preflight check. This can happen in single node clusters where the only node was drained. ([#124570](https://github.com/kubernetes/kubernetes/pull/124570), [@neolit123](https://github.com/neolit123))...

#### Load Balancing

- The  new flag `etcd-ready-timeout` has been added. It configures a timeout of an additional etcd check performed as part of readyz check. ([#111399](https://github.com/kubernetes/kubernetes/pull/111399), [@Argh4k](https://github.com/Argh4k))

- If `ComponentSLIs` feature gate is enabled, then `/metrics/slis` now becomes available on cloud-controller-manager allowing you to scrape health check metrics. ([#113340](https://github.com/kubernetes/kubernetes/pull/113340), [@Richabanker](https://gi...

- Removed `/livez` livezchecks for KMS v1 and v2 to ensure KMS health does not cause `kube-apiserver` restart. KMS health checks are still in place as a healthz and readiness checks. ([#120583](https://github.com/kubernetes/kubernetes/pull/120583), [@ritazh](https://github.com/ritazh))