### Introducing Graceful Node Shutdown (Alpha)

The `GracefulNodeShutdown` feature is now in Alpha. This allows kubelet to be aware of node system shutdowns, enabling graceful termination of pods during a system shutdown. This feature can be [enabled through feature gate](https://docs.k8s.io/concepts/architecture/nodes/#graceful-node-shutdown).

### Runtime log sanitation

- Introduced `v1alpha1` API for validating admission policies, enabling extensible admission control via CEL expressions (KEP  3488: CEL for Admission Control). To use, enable the `ValidatingAdmissionPolicy` feature gate and the `admissionregistration.k8s.io/v1alpha1` API via `--runtime-config`. ([#113314](https://g...

- Existing InTree AzureFile PVs which don't have a secret namespace defined will now work properly after enabling CSI migration - the namespace will be obtained from ClaimRef. ([#108000](https://github.com/kubernetes/kubernetes/pull/108000), [@RomanBednar](https://github.com/RomanBednar))

- Fix the bug that EndpointSlice for masters wasn't created after enabling EndpointSlice feature on a pre-existing cluster. ([#84421](https://github.com/kubernetes/kubernetes/pull/84421), [@tnqn](https://github.com/tnqn))

* The Stackdriver Metadata Agent addon now includes RBAC manifests, enabling it to watch nodes and pods. ([#57455](https://github.com/kubernetes/kubernetes/pull/57455), [@kawych](https://github.com/kawych))

  * Make kubeadm use the new CSR approver in v1.7 ([#46864](https://github.com/kubernetes/kubernetes/pull/46864), [@luxas](https://github.com/luxas))

  * Allow enabling multiple authorization modes at the same time ([#42557](https://github.com/kubernetes/kubernetes/pull/42557), [@xilabao](https://github.com/xilabao))

- Marked the feature gate `ExperimentalHostUserNamespaceDefaulting` as deprecated.

Kubeadm: Automate certificate copy between control planes in HA setups

- Joining control plane nodes to a HA cluster can now be simplified by enabling the optional automatic copy of certificates from an existing control plane node.
- You can now use `kubeadm init --experimental-upload-certs` and `kubeadm join --experimental-control-plane --certificate-key`.

SIG Storage is also introducing the following new storage features as alpha in Kubernetes 1.18:
- Windows CSI Support: Enabling containerized CSI node plugins in Windows via new [CSIProxy](https://github.com/kubernetes-csi/csi-proxy)

* The `--cluster-name` parameter has been added to kubeadm init, enabling users to specify the cluster name in kubeconfig. ([#60852](https://github.com/kubernetes/kubernetes/pull/60852), [@karan](https://github.com/karan))