- Remove prometheus cluster monitoring addon from kube-up ([#83442](https://github.com/kubernetes/kubernetes/pull/83442), [@serathius](https://github.com/serathius))
- SourcesReady provides the readiness of kubelet configuration sources such as apiserver update readiness. ([#81344](https://github.com/kubernetes/kubernetes/pull/81344), [@zouyee](https://github.com/zouyee))

specified) is `1s` which may be too small for some exec probes. Ensure that pods relying on this behavior are updated to correctly handle probe timeouts. See [configure probe](https://docs.k8s.io/tasks/configure-pod-container/configure-liveness-readiness-startup-probes/#configure-probes) section of the documentation for more details.

  - This change in behavior may be unexpected for some clusters and can be disabled by turning off the `ExecProbeTimeout` feature gate. This gate will be...

- Kube-apiserver: Each unique set of etcd server overrides specified with `--etcd-servers-overrides` surfaced health checks named `etcd-override-<index>` and `etcd-override-readiness-<index>`. These checks were still excluded by the `?exclude=etcd` and `?exclude=etcd-readiness` directives. ([#129438](https://github.com/kubernetes/kubernetes/pull/129438), [@pacoxu](https://github.com/pacoxu)) [SIG API Machinery and Testing]

* Fix incorrect conflict errors applying strategic merge patches to resources. ([#43871](https://github.com/kubernetes/kubernetes/pull/43871), [@liggitt](https://github.com/liggitt))

* Fix init container status reporting when active deadline is exceeded. ([#46305](https://github.com/kubernetes/kubernetes/pull/46305), [@sjenning](https://github.com/sjenning))

- [Conformance tests](https://github.com/kubernetes/kubernetes/pull/108592) added support for Windows
- New repository created for [Windows Operational Readiness](https://github.com/kubernetes-sigs/windows-operational-readiness)

### Moved container registry service from k8s.gcr.io to registry.k8s.io

## Changelog since v1.16.0

### Other notable changes

* Limit the body length of exec readiness/liveness probes. remote CRIs and Docker shim read a max of 16MB output of which the exec probe itself inspects 10kb. ([#82514](https://github.com/kubernetes/kubernetes/pull/82514), [@dims](https://github.com/dims))

- 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))

* kubeadm: Detect kubelet readiness and error out if the kubelet is unhealthy ([#51369](https://github.com/kubernetes/kubernetes/pull/51369), [@luxas](https://github.com/luxas))

- kubeadm: switched the kube-scheduler static Pod to use the endpoints `/livez` (for startup and liveness probes) and `/readyz` (for the readiness probe). Previously, `/healthz` was used for all probes, which is deprecated behavior in the scope of this component. ([#126945](https://github.com/kubernetes/kubernetes/pull/126945), [@liangyuanpeng](https://github.com/liangyuanpeng)) [SIG Cluster...

- If the user specifies an invalid timeout in the request URL, the request will be aborted with an HTTP 400.
  - in cases where the client specifies a timeout in the request URL, the overall request deadline is shortened now since the deadline is setup as soon as the request is received by the apiserver. ([#96901](https://github.com/kubernetes/kubernetes/pull/96901), [@tkashem](https://github.com/tkashem)) [SIG API Machinery and Testing]