* but an implemantation that encorporates the transport header(for
     * efficiency) might use a different initial bufferIndex. For example,
     * to eliminate copying data when writing NbtSession data one might
     * manage that 4 byte header specifically and therefore the initial
     * bufferIndex, and thus headerStart, would be 4).(NOTE: If one where
     * looking for a way to improve perfomance this is precisly what you

* Fix a scalability issue where high rates of event writes degraded etcd performance. ([#64539](https://github.com/kubernetes/kubernetes/pull/64539), [@ccding](https://github.com/ccding))
* Properly manage security groups for loadbalancer services on OpenStack. ([#65373](https://github.com/kubernetes/kubernetes/pull/65373), [@multi-io](https://github.com/multi-io))

  - [beta] In order to preserve safety guarantees the cluster no longer force deletes pods on un-responsive nodes and users are now warned if they try to force delete pods via the CLI. ([docs](http://kubernetes.io/docs/tasks/manage-stateful-set/scale-stateful-set/)) ([kubernetes/features#119](https://github.com/kubernetes/enhancements/issues/119))
- **Auth**

* DaemonSets [can now be updated by a rolling update](https://kubernetes.io/docs/tasks/manage-daemon/update-daemon-set).

## Action Required

### Certificates API

### CSIDriver policy for FSGroup graduates to Beta

The FSGroup's CSIDriver Policy is now beta in 1.20. This allows CSIDrivers to explicitly indicate if they want Kubernetes to manage permissions and ownership for their volumes via `fsgroup`. 

### Security Improvements for CSI Drivers (Alpha)

* Federation
  * federation api group is now **beta**
  * Services from all federated clusters are now registered in Cloud DNS (AWS and GCP).
* Stateful Apps:
  * **alpha** PetSets manage stateful apps
  * **alpha** Init containers provide one-time setup for stateful containers
* Updating:
  * Retry Pod/RC updates in kubectl rolling-update.
  * Stop 'kubectl drain' deleting pods with local storage.

* **Other objects**: no changes unless you explicitly request orphaning.

## Action Required Before Upgrading

- If you are using Kubernetes to manage `docker` containers, please be aware Kubernetes has been validated to work with docker 1.9.1, docker 1.11.2 (#23397), and docker 1.12.0 (#28698)

   ([#122830](https://github.com/kubernetes/kubernetes/pull/122830), [@p0lyn0mial](https://github.com/p0lyn0mial))
- Updated `ImageGCMaxAge` behavior in the kubelet to wait the `MaxAge` duration after the kubelet has restarted before garbage collecting.
   ([#123343](https://github.com/kubernetes/kubernetes/pull/123343), [@haircommander](https://github.com/haircommander))

        </field>
      </fields>
    </class>
    <class>
      <name>IssueManagement</name>
      <description>Information about the issue tracking (or bug tracking) system used to manage this
        project.</description>
      <version>4.0.0+</version>
      <fields>
        <field>
          <name>system</name>
          <version>4.0.0+</version>

#### DaemonSet
* [beta] DaemonSet supports history and rollback. See [Performing a Rollback on a DaemonSet](https://kubernetes.io/docs/tasks/manage-daemon/rollback-daemon-set/).

#### Deployments