- Client-go informers: fix an unlikely deadlock during informer startup. ([#136509](https://github.com/kubernetes/kubernetes/pull/136509), [@pohly](https://github.com/pohly)) [SIG API Machinery]

* Adds a metric apiserver_request_error_total to kube-apiserver. This metric tallies the number of request_errors encountered by verb, group, version, resource, subresource, scope, component, and code. ([#84777](https://github.com/kubernetes/kubernetes/pull/84777), [@RainbowMango](https://github.com/RainbowMango))

      * If you use the very rarely-used function `tf.keras.mixed_precision.experimental.get_layer_policy`:
          * Replace `tf.keras.mixed_precision.experimental.get_layer_policy(layer)` with `layer.dtype_policy`.

- Ephemeral containers graduated to beta and are now available by default. ([#105405](https://github.com/kubernetes/kubernetes/pull/105405), [@verb](https://github.com/verb))

 
## Changes by Kind

### Deprecation

- 'kubeadm: marked the sub-phase of ''init kubelet-finilize'' called ''experimental-cert-rotation''
  as deprecated and print a warning if it is used directly; it will be removed in
  a future release. Add a replacement sub-phase ''enable-client-cert-rotation''.' ([#124419](https://github.com/kubernetes/kubernetes/pull/124419), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]

    )
    response2.body.close()
  }

  @Test
  fun unmatchingPinnedCertificate() {
    enableTls()
    server.enqueue(MockResponse())

    // Pin publicobject.com's cert.
    client =
      client
        .newBuilder()
        .certificatePinner(
          CertificatePinner
            .Builder()
            .add(server.hostName, "sha1/DmxUShsZuNiqPQsX2Oi9uv2sCnw=")

   ([#113629](https://github.com/kubernetes/kubernetes/pull/113629), [@andrewsykim](https://github.com/andrewsykim))
- 'The iptables kube-proxy backend now process service/endpoint changes
  more efficiently in very large clusters.' ([#110268](https://github.com/kubernetes/kubernetes/pull/110268), [@danwinship](https://github.com/danwinship))
- '`CSIMigrationvSphere` was upgraded to GA and locked to true. Do not upgrade to K8s

- Pod spread constraints have been added in alpha. You can use these constraints to control how Pods are spread across the cluster among failure-domains. ([#77327](https://github.com/kubernetes/kubernetes/pull/77327), [#77760](...

  Docker:         v1.11.2
  Changelog (vs 55-8872-18-0)
    * Cherry-pick runc PR#608: Eliminate redundant parsing of mountinfo
    * Updated kubernetes to v1.4.5
    * Fixed a bug in e2fsprogs that caused mke2fs to take a very long time. Upstream fix: http://git.kernel.org/cgit/fs/ext2/e2fsprogs.git/commit/?h=next&id=d33e690fe7a6cbeb51349d9f2c7fb16a6ebec9c2
```

- Fix a panic in kubectl when creating secrets with an improper output type (#106354, @lauchokyip) [SIG CLI]
- Fix concurrent map access causing panics when logging timed-out API calls. (#106113, @marseel) [SIG API Machinery]
- Fixed very rare volume corruption when a pod is deleted while kubelet is offline.