##### Cluster Autoscaler

* Cluster autoscaler is now GA
* Cluster support size is increased to 1000 nodes
* Respect graceful pod termination of up to 10 minutes
* Handle zone stock-outs and failures
* Improve monitoring and error reporting

#### Container Runtime Interface (CRI)

// gay : Registry Services, LLC
// https://www.iana.org/domains/root/db/gay.html
gay

// gbiz : Charleston Road Registry Inc.
// https://www.iana.org/domains/root/db/gbiz.html
gbiz

// gdn : Joint Stock Company "Navigation-information systems"
// https://www.iana.org/domains/root/db/gdn.html
gdn

// gea : GEA Group Aktiengesellschaft
// https://www.iana.org/domains/root/db/gea.html
gea

### IPv4/IPv6 run

IPv4/IPv6 dual-stack has been reimplemented for 1.20 to support dual-stack Services, based on user and community feedback. If your cluster has dual-stack enabled, you can create Services which can use IPv4, IPv6, or both, and you can change this setting for existing Services. Details are available in updated [IPv4/IPv6 dual-stack docs](https://docs.k8s.io/concepts/services-networking/dual-stack/), which cover the nuanced array of options.

- Kube-proxy: on dual-stack mode, if it is not able to get the IP Family of an endpoint, logs it with level InfoV(4) instead of Warning, avoiding flooding the logs for endpoints without addresses ([#88934](https://github.com/kubernetes/kubernetes/pull/88934), [@aojea](https://github.com/aojea)) [SIG Network]

- Kubelet: Fix the volume manager didn't check the device mount state in the actual state of the world before marking the volume as detached. It may cause a pod to be stuck in the Terminating state due to the above issue when it was deleted. ([#129064](https://github.com/kubernetes/kubernetes/pull/129064), [@carlory](https://github.com/carlory)) [SIG Node]

## Dependencies

### Added

- `-- kube-controller-manager`
  `--node-cidr-mask-size-ipv4 int32`     Default: 24. Mask size for IPv4 node-cidr in dual-stack cluster.
`--node-cidr-mask-size-ipv6 int32`     Default: 64. Mask size for IPv6 node-cidr in dual-stack cluster.

    These 2 flags can be used only for dual-stack clusters. For non dual-stack clusters, continue to use  `--node-cidr-mask-size` flag to configure the mask size.

### IPv4/IPv6 Dual-stack Networking graduates to GA

[IPv4/IPv6 dual-stack networking](https://github.com/kubernetes/enhancements/tree/master/keps/sig-network/563-dual-stack) graduates to GA.
Since 1.21, Kubernetes clusters are enabled to support dual-stack networking by default.
In 1.23, the `IPv6DualStack` feature gate is removed.
The use of dual-stack networking is not mandatory.

- [IPv4/IPv6 dual-stack](https://kubernetes.io/docs/concepts/services-networking/dual-stack) enables the allocation of both IPv4 and IPv6 addresses to Pods and Services.

- Kubelet: Fix the volume manager didn't check the device mount state in the actual state of the world before marking the volume as detached. It may cause a pod to be stuck in the Terminating state due to the above issue when it was deleted. ([#129063](https://github.com/kubernetes/kubernetes/pull/129063), [@carlory](https://github.com/carlory)) [SIG Node]

## Dependencies

### Added

* Update to use go 1.11.13 ([#81542](https://github.com/kubernetes/kubernetes/pull/81542), [@BenTheElder](https://github.com/BenTheElder))
* Fix Azure client requests stuck issues on http.StatusTooManyRequests (HTTP Code 429). ([#81279](https://github.com/kubernetes/kubernetes/pull/81279), [@feiskyer](https://github.com/feiskyer))