grafana-replication-cluster.png...

- Kubeadm: during "join", don't re-add an etcd member if it already exists in the cluster. ([#92118](https://github.com/kubernetes/kubernetes/pull/92118), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]
- hyperkube: Use debian-hyperkube-base@v1.1.1 image
  

* Use Cluster Autoscaler 0.5.1, which fixes an issue in Cluster Autoscaler 0.5 where the cluster may be scaled up unnecessarily. Also the status of Cluster Autoscaler is now exposed in kube-system/cluster-autoscaler-status config map. ([#43745](https://github.com/kubernetes/kubernetes/pull/43745), [@mwielgus](https://github.com/mwielgus))

- `-- 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.

- Kubeadm: add the "--cluster-name" flag to the "kubeadm alpha kubeconfig user" to allow configuring the cluster name in the generated kubeconfig file ([#93992](https://github.com/kubernetes/kubernetes/pull/93992), [@prabhu43](https://github.com/prabhu43)) [SIG Cluster Lifecycle]

- One new field "InternalTrafficPolicy" in Service is added.
  It specifies if the cluster internal traffic should be routed to all endpoints or node-local endpoints only.
  "Cluster" routes internal traffic to a Service to all endpoints.
  "Local" routes traffic to node-local endpoints only, and traffic is dropped if no node-local endpoints are ready.

`system:aggregate-to-edit` role no longer includes write access to the Endpoints API. For new Kubernetes 1.22 clusters, the `edit` and `admin` roles will no longer include that access in newly created Kubernetes 1.22 clusters. This will have no affect on existing clusters upgrading to Kubernetes 1.22. To retain write access to Endpoints in the aggregated `edit` and `admin` roles for newly created 1.22 clusters, refer to https://github.com/kubernetes/website/pull/29025. ([#103704](https://github.com/kubernet...

- [KCCM - service controller]: enable connection draining for terminating pods upon node downscale by the cluster autoscaler. This is done by not reacting to the taint used by the cluster autoscaler to indicate that the node is going away soon, thus keeping the node referenced by the load balancer until the VM has been completely...

- The scheduling queue didn't notice any extenders' failures, it could miss some cluster events,
  and it could end up Pods rejected by Extenders stuck in unschedulable pod pool in 5min in the worst-case scenario.

feature, you might need to take some action immediately after upgrading. In multi-tenant clusters where not all users are trusted, you are advised to create appropriate quotas for two default priority classes, system-cluster-critical and system-node-critical, which are added to clusters by default. `ResourceQuota` should be created to limit users from creating Pods at these priorities if not all users of your cluster are trusted. We do not advise disabling this feature because critical system Pods rely...