- For `kubeadm`: add `--validity-period` flag for `kubeadm kubeconfig user` command. ([#100907](https://github.com/kubernetes/kubernetes/pull/100907), [@SataQiu](https://github.com/SataQiu))

## Changes by Kind

### Deprecation

- Added a [warning](https://k8s.io/blog/2020/09/03/warnings/) response when handling requests that set the deprecated `spec.externalID` field for a Node. ([#115944](https://github.com/kubernetes/kubernetes/pull/115944), [@SataQiu](https://github.com/SataQiu)) [SIG Node]

- Azure SDK and go-autorest API versions have been updated ([#79574](https://github.com/kubernetes/kubernetes/pull/79574))
- Azure API versions have been updated (container registry to 2018-09-01, network to 2018-08-01) ([#79583](https://github.com/kubernetes/kubernetes/pull/79583))
- kube-addon-manager has been updated to v9.0.2 ([#80861](https://github.com/kubernetes/kubernetes/pull/80861))

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