- We have added a new Priority & Fairness rule that exempts all probes (/readyz, /healthz, /livez) to prevent 
  restarting of "healthy" kube-apiserver instance(s) by kubelet. ([#101111](https://github.com/kubernetes/kubernetes/pull/101111), [@tkashem](https://github.com/tkashem)) [SIG API Machinery]

### Feature

- Fixes #115825. Kube-proxy will now include the `healthz` state in its response to the LB HC as to avoid indicating to the LB that it should use the node in question when Kube-proxy is not healthy. ([#111661](https://github.com/kubernetes/kubernetes/pull/111661), [@alexanderConstantinescu](https://github.com/alexanderConstantinescu)) [SIG Network]

- During device plugin allocation, resources requested by the pod can only be allocated if the device plugin has registered itself to kubelet AND healthy devices are present on the node to be allocated. If these conditions are not sattsfied, the pod would fail with `UnexpectedAdmissionError` error. ([#116376](https://github.com/kubernetes/kubernetes/pull/116376), [@swatisehgal](https://github.com/swatisehgal))...

* Add etcd connectivity endpoint to healthz ([#49412](https://github.com/kubernetes/kubernetes/pull/49412), [@bjhaid](https://github.com/bjhaid))
* kube-proxy will emit "FailedToStartNodeHealthcheck" event when fails to start healthz server. ([#49267](https://github.com/kubernetes/kubernetes/pull/49267), [@MrHohn](https://github.com/MrHohn))

- Kubeadm: modified the etcd static Pod `liveness` and `readiness` probes to use a new etcd `v3.5.3+` HTTP(s) health check endpoint `/health?serializable=true` that allows to track the health of individual etcd members and not fail all members if a single member is not healthy in the etcd cluster. ([#110072](https://github.com/kubernetes/kubernetes/pull/110072), [@neolit123](https://github.com/neolit123))

- Add a new Priority and Fairness rule that exempts all probes (`/readyz`, `/healthz`, `/livez`) to prevent restarting of healthy `kube-apiserver` instance by kubelet. ([#100678](https://github.com/kubernetes/kubernetes/pull/100678), [@tkashem](https://github.com/tkashem))

running in 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...

- Health check of kube-controller-manager now includes each controller. ([#104667](https://github.com/kubernetes/kubernetes/pull/104667), [@jiahuif](https://github.com/jiahuif))

- A new API server flag `--encryption-provider-config-automatic-reload` was added to control when the encryption config should be automatically reloaded without needing to restart the server.  All KMS plugins are now merged into a single healthz check at `/healthz/kms-providers` when reload is enabled, or when only KMS v2 plugins are used. ([#113529](https://github.com/kubernetes/kubernetes/pull/113529), [@enj](https://github.com/enj))

   ([#123271](https://github.com/kubernetes/kubernetes/pull/123271), [@neolit123](https://github.com/neolit123))
- kubeadm: improved the overall logic, error handling, and output messages when waiting for the kubelet and API server `/healthz` endpoints to return `OK`. The kubelet and API server checks no longer ran in parallel, but one after another (in serial).
   ([#121958](https://github.com/kubernetes/kubernetes/pull/121958), [@neolit123](https://github.com/neolit123))