*  Fix: OkHttp no longer shares timeouts between pooled connections. This was
    causing some applications to crash when connections were reused.
 *  Fix: `OkApacheClient` now allows an empty `PUT` and `POST`.
 *  Fix: Websockets no longer rebuffer socket streams.
 *  Fix: Websockets are now better at handling close frames.
 *  Fix: Content type matching is now case insensitive.

kube-controller manager now use SO_REUSEPORT socket option when listening on address defined by --bind-address and --secure-port flags, when running on Unix systems (Windows is NOT supported). This allows to run multiple instances of those processes on a single host with the same configuration, which allows to update/restart them in a graceful way, without causing downtime. ([#88893](https://github.com/kubernetes/kubernetes/pull/88893), [@invidian](https://github.com/invidian)) [SIG API Machinery, Scheduling...

- Graduated relaxed DNS search string validation to GA. For the Pod API, `.spec.dnsConfig.searches`
  now allows an underscore (`_`) where a dash (`-`) would be allowed, and it allows search strings be a single dot `.`. ([#132036](https://github.com/kubernetes/kubernetes/pull/132036), [@adrianmoisey](https://github.com/adrianmoisey)) [SIG Network and Testing]

  * Allow configuration of a single security group for ELBs ([#45500](https://github.com/kubernetes/kubernetes/pull/45500), [@nbutton23](https://github.com/nbutton23))

  * Remove check that forces loadBalancerSourceRanges to be 0.0.0.0/0. ([#38636](https://github.com/kubernetes/kubernetes/pull/38636), [@dhawal55](https://github.com/dhawal55))

   * an application-specified ordering of lock acquisitions. The application defines the allowed
   * ordering with an {@code Enum} whose values each correspond to a lock type. The order in which
   * the values are declared dictates the allowed order of lock acquisition. In other words, locks
   * corresponding to smaller values of {@link Enum#ordinal()} should only be acquired before locks

   ([#123641](https://github.com/kubernetes/kubernetes/pull/123641), [@liggitt](https://github.com/liggitt))

- **Volume Extension**: There are quite a few enhancements in this release that pertain to volumes and volume modifications. Volume resizing support in CSI specs is moving to beta which allows for any CSI spec volume plugin to be resizable.

### Additional Notable Feature Updates

* The Kubelet's deprecated `--allow-privileged` flag now defaults to true. This enables users to stop setting `--allow-privileged` in order to transition to `PodSecurityPolicy`. Previously, users had to continue setting `--allow-privileged`, because the default was false. ([#63442](https://github.com/kubernetes/kubernetes/pull/63442), [@mtaufen](https://github.com/mtaufen))

### Promoted Server Side Unknown Field Validation to Beta

Promoted the `ServerSideFieldValidation` feature gate to beta (on by default). This allows optionally triggering schema validation on the API server that errors when unknown fields are detected. This allows the removal of client-side validation from kubectl while maintaining the same core functionality of erroring out on requests that contain unknown or invalid fields.

 * <code>getAllByAddress</code> to create a new NbtAddress instance. This
 * class is symmetric with {@link java.net.InetAddress}.
 *
 * <p><b>About NetBIOS:</b> The NetBIOS name
 * service is a dynamic distributed service that allows hosts to resolve
 * names by broadcasting a query, directing queries to a server such as
 * Samba or WINS. NetBIOS is currently the primary networking layer for
 * providing name service, datagram service, and session service to the