## Major Themes

- StatefulSets (ex-PetSets)
  - StatefulSets are beta now (fixes and stabilization)
- Improved Federation Support
  - New command: `kubefed`
  - DaemonSets
  - Deployments
  - ConfigMaps
- Simplified Cluster Deployment
  - Improvements to `kubeadm`
  - HA Setup for Master
- Node Robustness and Extensibility

### kubectl rolling-update: < v1.4.0 client vs >=v1.4.0 cluster

Old version kubectl's rolling-update command is compatible with Kubernetes 1.4 and higher only if you specify a new replication controller name. You will need to update to kubectl 1.4 or higher to use the rolling update command against a 1.4 cluster if you want to keep the original name, or you'll have to do two rolling updates.

  - Server-side feature gate: `TranslateStreamCloseWebsocketRequests`
  - Client-side (kubectl) feature gate: `KUBECTL_REMOTE_COMMAND_WEBSOCKETS`
  - To disable RemoteCommand over WebSockets for kubectl, the environment variable feature gate must be explicitly set to `false`: `KUBECTL_REMOTE_COMMAND_WEBSOCKETS=false`.
   ([#123281](https://github.com/kubernetes/kubernetes/pull/123281), [@seans3](https://github.com/seans3))