### Volumes
* StorageClass pre-installed and set as default on Azure, AWS, GCE, OpenStack, and vSphere.
  * This is something to pay close attention to if you’ve been using Kubernetes for a while, because it changes the default behavior of PersistentVolumeClaim objects on these clouds.

    /** The key of the configuration. e.g.  */
    String CRAWLER_DOCUMENT_HTML_DEFAULT_INCLUDE_SEARCH_PATTERNS = "crawler.document.html.default.include.search.patterns";

    /** The key of the configuration. e.g.  */
    String CRAWLER_DOCUMENT_HTML_DEFAULT_EXCLUDE_SEARCH_PATTERNS = "crawler.document.html.default.exclude.search.patterns";

- Feature gates CSIMigration to Beta (on by default) and CSIMigrationGCE to Beta (off by default since it requires installation of the GCE PD CSI Driver) ([#85231](https://github.com/kubernete...

### Cluster-wide seccomp defaults

A new alpha feature gate `SeccompDefault` has been added to the kubelet, together with a corresponding command line flag `--seccomp-default` and kubelet configuration. If both are enabled, then the kubelet's behavior changes for pods that don't explicitly set a seccomp profile.

- Updated `kube-openapi` to remove invalid defaults: OpenAPI spec no longer includes default of `{}` for certain fields where it did not make sense. ([#120757](https://github.com/kubernetes/kubernetes/pull/120757), [@alexzielenski](https://github.com/alexzielenski))

  - `failurePolicy` default changed from `Ignore` to `Fail` for v1
  - `matchPolicy` default changed from `Exact` to `Equivalent` for v1
  - `timeout` default changed from `30s` to `10s` for v1
  - `sideEffects` default value is removed, and the field made required, and only `None` and `NoneOnDryRun` are permitted for v1

In 1.23, the `PodSecurity` feature gate is enabled by default.

### Container Runtime Interface (CRI) v1 is default

The Kubelet now supports the CRI `v1` API, which is now the project-wide default.
If a container runtime does not support the `v1` API, Kubernetes will fall back to the `v1alpha2` implementation.

#### CustomResourceDefinition Defaulting

CustomResourceDefinitions also have new support for defaulting, with defaults specified using the `default` keyword in the OpenAPI validation schema. Defaults are set for unspecified fields in an object sent to the API, and when reading from etcd.

Defaulting will be available as alpha in Kubernetes 1.15 and requires structural schemas.

  * Special notice for kube-proxy in 1.7+ (including 1.7.0):
    * Healthz server (/healthz) will be served on 0.0.0.0:10256 by default.
    * Metrics server (/metrics and /proxyMode) will be served on 127.0.0.1:10249 by default.
    * Metrics server will continue serving /healthz.


# v1.7.2

- Graduated ServerSideFieldValidation to `beta`. Schema validation is performed server-side and requests will receive warnings for any invalid/unknown fields by default. ([#110178](https://github.com/kubernetes/kubernetes/pull/110178),...