be sure to upgrade Docker before upgrading Kubernetes. ([#57845](https://github.com/kubernetes/kubernetes/pull/57845), [@yujuhong](https://github.com/yujuhong))

* The Container Runtime Interface (CRI) version has increased from v1alpha1 to v1alpha2. Runtimes implementing the CRI will need to update to the new version, which configures container namespaces using an enumeration rather than booleans. This change to the alpha API is not backwards compatible; implementations of the CRI such...

  to kubelet config ([#112136](https://github.com/kubernetes/kubernetes/pull/112136), [@pacoxu](https://github.com/pacoxu))
- `resource.k8s.io/v1alpha1` was replaced with `resource.k8s.io/v1alpha2`. Before
  upgrading a cluster, all objects in resource.k8s.io/v1alpha1 (ResourceClaim, ResourceClaimTemplate,
  ResourceClass, PodScheduling) must be deleted. The changes are internal, so

*   The API group/version for the kube-proxy configuration has changed from `componentconfig/v1alpha1` to `kubeproxy.config.k8s.io/v1alpha1`. If you are using a config file for kube-proxy instead of the command line flags, you must change its apiVersion to `kubeproxy.config.k8s.io/v1alpha1`. ([#53645](https://github.com/kubernetes/kubernetes/pull/53645), [@xiangpengzhao](https://github.com/xiangpengzhao))

- Storage capacity tracking (= the CSIStorageCapacity feature) graduates to Beta and enabled by default, storage.k8s.io/v1alpha1/VolumeAttachment and storage.k8s.io/v1alpha1/CSIStorageCapacity objects are deprecated ([#99641](https://github.com/kubernetes/kubernetes/pull/99641), [@pohly](https://github.com/pohly))

    * rbac.authorization.k8s.io/v1alpha1
    * settings.k8s.io/v1alpha1
    * If you wish to continue using them in v1.8, please enable them explicitly using the `--runtime-config` flag of the apiserver (for example, `--runtime-config="rbac.authorization.k8s.io/v1alpha1,settings.k8s.io/v1alpha1"`)

  - Scheduler Extenders can now be configured in the v1alpha2 component config ([#88768](https://github.com/kubernetes/kubernetes/pull/88768), [@damemi](https://github.com/damemi)) [SIG Release, Scheduling and Testing]

- Kubelet: plugins for dynamic resource allocation may use the `v1alpha3` API instead of v1alpha2 if they want to do prepare/unprepare operations in batches. ([#119012](https://github.com/kubernetes/kubernetes/pull/119012), [@pohly](https://github.com/pohly))

* [action required] kubeadm: The `v1alpha2` config API has been removed. ([#69055](https://github.com/kubernetes/kubernetes/pull/69055), [@fabriziopandini](https://github.com/fabriziopandini))
    * Please convert your `v1alpha2` configuration files to `v1alpha3` using the
    * `kubeadm config migrate` command of kubeadm v1.12.x

### Other notable changes

If a container runtime does not support the `v1` API, Kubernetes will fall back to the `v1alpha2` implementation.
There is no intermediate action required by end-users, because `v1` and `v1alpha2` do not differ in their implementation.
It is likely that `v1alpha2` will be removed in one of the future Kubernetes releases to be able to develop `v1`.

### Structured logging graduate to Beta

- The `client.authentication.k8s.io/v1alpha1` ExecCredential has been removed. If you are using a client-go credential plugin that relies on the v1alpha1 API please contact the distributor of your plugin for instructions on how to migrate to the v1 API. ([#108616](https://github.com/kubernetes/kubernetes/pull/108616), [@margocrawf](https://github.com/margocrawf))