machines and reports it as part of node metrics to heapster. This API call fails for VMware and VirtualBox virtualization environments. This issue is not present in bare metal Windows deployments, in Hyper-V, or on some of the popular public cloud providers.

*   If you run `kubectl get po` while the API server in unreachable, a misleading error is returned: `the server doesn't have a resource type "po"`. To work around this issue, specify the full resource name in the command instead...

* Use "k8s.gcr.io" for container images rather than "gcr.io/google_containers".  This is just a redirect, for now, so should not impact anyone materially.   ([#54174](https://github.com/kubernetes/kubernetes/pull/54174), [@thockin](https://github.com/thockin))
    * Documentation and tools should all convert to the new name. Users should take note of this in case they see this new name in the system.

## Urgent Upgrade Notes

### (No, really, you MUST read this before you upgrade)

**Note**: This only impacts the cluster if the ServiceAccount admission plugin is used (most cluster should have this on by default as recommended in https://kubernetes.io/docs/reference/access-authn-authz/admission-controllers/#serviceaccount), the `kubernetes.io/enforce-mountable-secrets` annotation is used by a service account (this annotation is not added by default), and Pods are using ephemeral containers.

- The alpha `Initializers` admission plugin is no longer enabled by default. This matches the off-by-default behavior of the alpha API which drives initializer behavior. ([#66039](https://gi...

until all results are retrieved.  The resulting list is identical to a list call that does not perform chunking, thanks to capabilities provided by etcd3.  This allows the server to use less memory and CPU when very large lists are returned. This feature is gated as APIListChunking and is not enabled by default. The 1.9 release will begin using this by default.([#48921](https://github.com/kubernetes/kubernetes/pull/48921))

* Pods that are marked for deletion and have exceeded their grace...

   1. Currently, if users were to explicitly specify CacheSize of 0 for KMS provider, they would end-up with a provider that caches up to 1000 keys. This PR changes this behavior.
      Post this PR, when users supply 0 for CacheSize this will result in a validation error.
   2. CacheSize type was changed from int32 to *int32. This allows defaulting logic to differentiate between cases where users explicitly supplied 0 vs. not supplied any value.

- client-go discovery clients constructed using `NewDiscoveryClientForConfig` or `NewDiscov...

true` and declare ports, get the `hostPort` field set automatically. Previously this would happen in the PodTemplate of a Deployment, DaemonSet or other workload API.  Now `hostPort` will only be set when an actual Pod is being created.  If this presents a problem, setting the feature gate "DefaultHostNetworkHostPortsInPodTemplates" to true will revert this behavior.  Please file a kubernetes bug if you need to do this. ([#117696](https://github.com/kubernetes/kubernetes/pull/117696), [@thockin](...

Kubernetes 1.8 caused the API server to accept a request with incorrect case and coerce it to correct case, but this behaviour has been fixed in 1.11 and the API server will once again be enforcing the correct case. It’s worth noting that during this time, the `kubectl` tool continued to enforce case-sensitive keys, so users that strictly manage resources with `kubectl` will be unaffected by this change. ([#65034](https://github.com/kubernetes/kubernetes/pull/65034), [@caesarxuchao](https://github.com/caesarxuchao))...