* Changes secret, configMap, downwardAPI and projected volumes to mount read-only, instead of allowing applications to write data and then reverting it automatically. Until version 1.11, setting the feature gate ReadOnlyAPIDataVolumes=false will preserve the old behavior. ([#58720](https://github.com/kubernetes/kubernetes/pull/58720), [@joelsmith](https://github.com/joelsmith))

* Changes secret, configMap, downwardAPI and projected volumes to mount read-only, instead of allowing applications to write data and then reverting it automatically. Until version 1.11, setting the feature gate ReadOnlyAPIDataVolumes=false will preserve the old behavior. ([#58720](https://github.com/kubernetes/kubernetes/pull/58720), [@joelsmith](https://github.com/joelsmith))

    * platforms would be satisfied by manually-created PersistentVolume objects.
    * Administrators can choose to disable this behavior by deleting the automatically
    * installed StorageClass API object. Alternatively, administrators may choose to
    * keep the automatically installed StorageClass and only disable the defaulting
    * behavior by removing the "is-default-class" annotation from the StorageClass
    * API object.

- When using `kubectl replace` (or the equivalent API call) on a Service, the caller no longer needs to do a read-modify-write cycle to fetch the allocated values for `.spec.clusterIP` and `.spec.ports[].nodePort`.  Instead the API server will automatically carry these forward from the original object when the new object does not specify them. ([#104673](https://github.com/kubernetes/kubernetes/pull/104673), [@thockin](https://github.com/thockin)) [SIG Network]

- Kubeadm init phase certs now support the `--csr-only` option, simplifying custom CA creation.
- `kubeadm join --experimental-control-plane` now automatically adds a new etcd member for `local etcd` mode, further simplifying required tasks for HA clusters setup.
- Improvements were made to `kubeadm reset` related to cleaning  etcd and notifying the user about the state of iptables.

    * Change chain name to IP-MASQ to be compatible with the pre-injected masquerade rules.
* If `TaintNodesByCondition` is enabled, add `node.kubernetes.io/unschedulable` and `node.kubernetes.io/network-unavailable` automatically to DaemonSet pods. ([#64954](https://github.com/kubernetes/kubernetes/pull/64954), [@k82cn](https://github.com/k82cn))

- Kubelet now cleans up orphaned volume directories automatically ([#95301](https://github.com/kubernetes/kubernetes/pull/95301), [@lorenz](https://github.com/lorenz)) [SIG Node and Storage]

- When using `kubectl replace` (or the equivalent API call) on a Service, the caller no longer needs to do a read-modify-write cycle to fetch the allocated values for `.spec.clusterIP` and `.spec.ports[].nodePort`.  Instead the API server will automatically carry these forward from the original object when the new object does not specify them. ([#104674](https://github.com/kubernetes/kubernetes/pull/104674), [@thockin](https://github.com/thockin)) [SIG Network]

   ([#123737](https://github.com/kubernetes/kubernetes/pull/123737), [@enj](https://github.com/enj))

- Apiservers based on k8s.io/apiserver with delegated authn based on cluster authentication will automatically update to new authentication information when the authoritative configmap is updated. ([#85004](https://github.com/kubernetes/kubernetes/pull/85004), [@deads2k](https://github.com/deads2k))