- Added warnings about workload resources (Pods, ReplicaSets, Deployments, Jobs, CronJobs, or ReplicationControllers) whose names are not valid DNS labels. ([#114412](https://github.com/kubernetes/kubernetes/pull/114412), [@thockin](https://github.com/thockin))

- API

  - The following APIs are no longer served by default:

    - All resources under `apps/v1beta1` and `apps/v1beta2` - use `apps/v1` instead
    - `daemonsets`, `deployments`, `replicasets` resources under `extensions/v1beta1` - use `apps/v1` instead
    - `networkpolicies` resources under `extensions/v1beta1` - use `networking.k8s.io/v1` instead

* Make etcd cache size configurable ([#23914](https://github.com/kubernetes/kubernetes/pull/23914), [@jsravn](https://github.com/jsravn))
* Drain pods created from ReplicaSets in 'kubectl drain' ([#23689](https://github.com/kubernetes/kubernetes/pull/23689), [@maclof](https://github.com/maclof))

- When scaling down a ReplicaSet, delete doubled up replicas first, where a "doubled up replica" is defined as one that is on the same node as an active replica belonging to a related ReplicaSet.  ReplicaSets are considered "related" if they have a common controller (typically a Deployment). ([#80004](https://github.com/kubernetes/kubernetes/pull/80004), [@Miciah](https://github.com/Miciah))

### Deprecation

#### kube-apiserver:
- the following deprecated APIs can no longer be served:
  - All resources under `apps/v1beta1` and `apps/v1beta2` - use `apps/v1` instead
  - `daemonsets`, `deployments`, `replicasets` resources under `extensions/v1beta1` - use `apps/v1` instead
  - `networkpolicies` resources under `extensions/v1beta1` - use `networking.k8s.io/v1` instead

- When downscaling ReplicaSets, ready and creation timestamps are compared in a logarithmic scale. ([#99212](https://github.com/kubernetes/kubernetes/pull/99212), [@damemi](https://github.com/damemi)) [SIG Apps and Testing]

* Deployment will stop adding pod-template-hash labels/selector to ReplicaSets and Pods it adopts. Resources created by Deployments are not affected (will still have pod-template-hash labels/selector).  ([#61615](https://github.com/kubernetes/kubernetes/pull/61615), [@janetkuo](https://github.com/janetkuo))

* Add-on manifests now use the apps/v1 API for DaemonSets, Deployments, and ReplicaSets ([#72203](https://github.com/kubernetes/kubernetes/pull/72203), [@liggitt](https://github.com/liggitt))

- `kubectl events --for` will also support fully qualified names such as replicasets.apps,
  etc. ([#117034](https://github.com/kubernetes/kubernetes/pull/117034), [@ardaguclu](https://github.com/ardaguclu))

* Cluster Autoscaler 1.0.1 ([#54298](https://github.com/kubernetes/kubernetes/pull/54298), [@mwielgus](https://github.com/mwielgus))
* Resolves forbidden error when accessing replicasets and daemonsets via the apps API group ([#54309](https://github.com/kubernetes/kubernetes/pull/54309), [@liggitt](https://github.com/liggitt))