## Changelog since v1.27.0

## Urgent Upgrade Notes 

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

- Action required for the custom scheduler plugin developers. 
  Here's the breaking change in `EnqueueExtension` in the scheduling framework. 

- Service session affinity timeout tests are no longer required for Kubernetes network plugin conformance due to variations in existing implementations. New conformance tests will be developed to better express conformance in future releases. ([#112806](https://github.com/kubernetes/kubernetes/pull/112806), [@dcbw](https://github.com/dcbw)) [SIG Architecture, Network and Testing]

    * The body size limit does not apply to subresources like pods/proxy that proxy request content to another server.
* Kustomize is developed in its own repo https://github.com/kubernetes-sigs/kustomize ([#73033](https://github.com/kubernetes/kubernetes/pull/73033), [@Liujingfang1](https://github.com/Liujingfang1))
    * This PR added a new subcommand `kustomize` in kubectl. 

With CSI the Kubernetes volume layer becomes truly extensible, allowing third party storage developers to write drivers making their storage systems available in Kubernetes without having to touch the core code.

CSI was first introduction as alpha in Kubernetes v1.9 and moved to beta in Kubernetes v1.10.

PSP as an admission controller resource is being deprecated. Deployed PodSecurityPolicy's will keep working until version 1.25, their target removal from the codebase. A new feature, with a working title of "PSP replacement policy", is being developed in [KEP-2579](https://features.k8s.io/2579). To learn more, read [PodSecurityPolicy Deprecation: Past, Present, and Future](https://blog.k8s.io/2021/04/06/podsecuritypolicy-deprecation-past-present-and-future/).

* Deprecate kubectl rolling-update  ([#61285](https://github.com/kubernetes/kubernetes/pull/61285), [@soltysh](https://github.com/soltysh))
* client-go developers: the new dynamic client is easier to use and the old is deprecated, you must switch. ([#62913](https://github.com/kubernetes/kubernetes/pull/62913), [@deads2k](https://github.com/deads2k))

### Other (Cleanup or Flake)

- Service session affinity timeout tests are no longer required for Kubernetes network plugin conformance due to variations in existing implementations. New conformance tests will be developed to better express conformance in future releases. ([#112806](https://github.com/kubernetes/kubernetes/pull/112806), [@dcbw](https://github.com/dcbw)) [SIG Architecture, Network and Testing]

## Dependencies

### Added