* Add ready replicas in Deployments ([#37959](https://github.com/kubernetes/kubernetes/pull/37959), [@kargakis](https://github.com/kargakis))
* Remove all MAINTAINER statements in Dockerfiles in the codebase as they are deprecated by docker ([#38927](https://github.com/kubernetes/kubernetes/pull/38927), [@luxas](https://github.com/luxas))

- the `ClusterStatus` struct present in the kubeadm-config ConfigMap is deprecated and will be removed in a future version. It is going to be maintained by kubeadm until it gets removed. The same information can be found on `etcd` and `kube-apiserver` pod annotations, `kubeadm.kubernetes.io/etcd.advertise-client-urls` and `kubeadm.kubernetes.io/kube-apiserver.advertise-address.endpoint` respectively....

## Changelog since v1.16.11

## Changes by Kind

### API Change

- Fixed: log timestamps now include trailing zeros to maintain a fixed width ([#91207](https://github.com/kubernetes/kubernetes/pull/91207), [@iamchuckss](https://github.com/iamchuckss)) [SIG Apps and Node]

### Bug or Regression

  * Clean up blackhole routes when using kubenet ([#47572](https://github.com/kubernetes/kubernetes/pull/47572), [@justinsb](https://github.com/justinsb))

  * Maintain a cache of all instances, to fix problem with > 200 nodes with ELBs ([#47410](https://github.com/kubernetes/kubernetes/pull/47410), [@justinsb](https://github.com/justinsb))

- Fixed the disruption controller's PDB status synchronization to maintain all PDB conditions during an update. ([#122056](https://github.com/kubernetes/kubernetes/pull/122056), [@dhenkel92](https://github.com/dhenkel92)) [SIG Apps]

## Changelog since v1.17.7

## Changes by Kind

### API Change

- Fixed: log timestamps now include trailing zeros to maintain a fixed width ([#91207](https://github.com/kubernetes/kubernetes/pull/91207), [@iamchuckss](https://github.com/iamchuckss)) [SIG Apps and Node]

### Bug or Regression

- Kube-apiserver now maintains a Lease object to identify itself: 
  - The feature is under feature gate `APIServerIdentity`. 

* Upgraded and relaxed dependencies for package extras `all` (including new Uvicorn version), when you install `"fastapi[all]"`.
* New docs about how to [**Help Maintain FastAPI**](https://fastapi.tiangolo.com/help-fastapi/#help-maintain-fastapi).

### Features

* ⬆️ Upgrade and relax dependencies for extras "all". PR [#5634](https://github.com/tiangolo/fastapi/pull/5634) by [@tiangolo](https://github.com/tiangolo).

* The Rackspace cloud provider has been removed after a long deprecation period. It was deprecated because it duplicates a lot of the OpenStack logic and can no longer be maintained. Please use the OpenStack cloud provider instead. ([#52855](https://github.com/kubernetes/kubernetes/pull/52855), [@NickrenREN](https://github.com/NickrenREN))

[https://github.com/kubernetes/kubernetes/issues/49213](https://github.com/kubernetes/kubernetes/issues/49213) sig-cluster-lifecycle has decided to phase out the cluster/ directory over the next couple of releases in favor of deployment automations maintained outside of the core repo and outside of kubernetes orgs. ([@kubernetes/sig-cluster-lifecycle-misc](https://github.com/orgs/kubernetes/teams/sig-cluster-lifecycle-misc))

    * Remove deprecated ContainerVM support from GCE kube-up. ...