- Alpha implementation of Kubectl Command Headers: SIG CLI KEP 859 enabled when KUBECTL_COMMAND_HEADERS environment variable set on the client command line.
  - To enable: export KUBECTL_COMMAND_HEADERS=1; kubectl ... ([#98952](https://github.com/kubernetes/kubernetes/pull/98952), [@seans3](https://github.com/seans3)) [SIG API Machinery and CLI]

    - [Garbage Collector](#garbage-collector)
    - [kubeadm](#kubeadm-2)
    - [kubectl](#kubectl-1)
      - [New Commands](#new-commands)
      - [Create subcommands](#create-subcommands)
      - [Updates to existing commands](#updates-to-existing-commands)
      - [Updates to apply](#updates-to-apply)
      - [Updates to edit](#updates-to-edit)
      - [Bug fixes](#bug-fixes)

  spec with the `--serviceaccount` flag.

- `kubectl proxy` now correctly handles the `exec`, `attach`, and
  `portforward` commands.  You must pass `--disable-filter` to the command to allow these commands.

- Added `cronjobs.batch` to "all", so that `kubectl get all` returns them.

- Added flag `--include-uninitialized` to `kubectl annotate`, `apply`, `edit-last-applied`,

  - kubeadm now handles air-gapped environments by using the local client version as a fallback.
  - Some kubeadm commands are now allowed to work in a completely offline mode.
- Certificate handling improvements:
  - Renew certs as part of upgrade.
  - New `kubeadm alpha phase certs renew` command for renewing certificates.
  - Certificates created with kubeadm now have improved uniqueness of Distinguished Name fields.

### CLI Improvements

- Added `kubeadm upgrade node`. This command can be used to upgrade both secondary control-plane nodes and worker nodes. The `kubeadm upgrade node config` and `kubeadm upgrade node experimental-control-plane` commands are now deprecated. ([#78408](https://github.com/kubernetes/kubernetes/pull/78408), [@fabriziopandini](https://github.com/fabriziopandini))

- kube-scheduler dropped support for configuration files with apiVersion `componentconfig/v1alpha1`. Ensure kube-scheduler is configured using command-line flags or a configuration file with apiVersion `kubescheduler.config.k8s.io/v1alpha1` before upgrading to 1.13.
- kubectl

- Kubeadm: deprecate self-hosting support. The experimental command "kubeadm alpha self-hosting" is now deprecated and will be removed in a future release. ([#95125](https://github.com/kubernetes/kubernetes/pull/95125), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]

- The helping message of commands which have sub-commands is now clearer and more instructive. It will show the full command instead of `kubectl <command> --help ...`
  

- If a bad flag is supplied to a kubectl command, only a tip to run `--help` is printed, instead of the usage menu.  Usage menu is printed upon running `kubectl command --help`. ([#82423](https://github.com/kubernetes/kubernetes/pull/82423), [@sallyom](https://github.com/sallyom))

*   Fixed an issue where `kubectl set` commands occasionally encountered conversion errors for ReplicaSet and DaemonSet objects ([#53158](https://github.com/kubernetes/kubernetes/pull/53158),[ @liggitt](https://github.com/liggitt))

### **Cluster Lifecycle**

#### **API Server**