**Affected Versions**:

    * ServiceDelimiter string Delimiter to use to separate overridden services (multiple services) Defaults to "&"
    * ServicenameDelimiter string Delimiter to use to separate servicename from its configuration parameters Defaults "|"
    * OverrideSeparator string Delimiter to use to separate region of occurrence, url and signing region for each override Defaults to ","

- Kubeadm: fix a bug where file copy(backup) could not be executed correctly on Windows platform during upgrade ([#117861](https://github.com/kubernetes/kubernetes/pull/117861), [@SataQiu](https://github.com/SataQiu)) [SIG Cluster Lifecycle]

- Sync node status during kubelet node shutdown.
  Adds an pod admission handler that rejects new pods when the node is in progress of shutting down. ([#98005](https://github.com/kubernetes/kubernetes/pull/98005), [@wzshiming](https://github.com/wzshiming)) [SIG Node]

### Instrumentation

In v1.9 we focused on improving stability of the components owned by the SIG, including Heapster, Custom Metrics API adapters for Prometheus, and Stackdriver.

  a bug in the transforming informer during the Resync operation, 
  by making the transforming function idempotent. ([#124352](https://github.com/kubernetes/kubernetes/pull/124352), [@wojtek-t](https://github.com/wojtek-t)) [SIG API Machinery and Scheduling]

- Remove ready file and its directory (which is created during volume SetUp) during emptyDir volume TearDown. ([#95770](https://github.com/kubernetes/kubernetes/pull/95770), [@jingxu97](https://github.com/jingxu97)) [SIG Storage]

### Other (Cleanup or Flake)

    2. Remove the `kubeadm.alpha.kubernetes.io/cri-socket` annotation from nodes during upgrade operations.
    3. Remove the `--container-runtime-endpoint` flag from the `/var/lib/kubelet/kubeadm-flags.env` file during upgrades. ([#131981](https://github.com/kubernetes/kubernetes/pull/131981), [@HirazawaUi](https://github.com/HirazawaUi)) [SIG Cluster Lifecycle]

correct these files before upgrading.** When specifying keys in JSON resource definitions during direct API server communication, the keys are case-sensitive. A bug introduced in 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...

  Don't use these flags. Using deprecated flags causes the server to print a warning. Using a removed flag causes the server to abort the startup.

* The following deprecated flags were removed from `kubelet`:

  * `api-servers` - add apiserver addresses to the kubeconfig file instead.