controller & Replicaset**: the DELETE request of a replication controller or a replicaset becomes asynchronous by default. The object will continue to exist in the key-value store for some time. The API server will set its metadata.deletionTimestamp, add the "orphan" finalizer to its metadata.finalizers. The object will be deleted from the key-value store after the garbage collector orphans its dependents. Please refer to this [user-guide](http://kubernetes.io/docs/user-guide/garbage-collector/) for more information...

- Ingress objects are now persisted in etcd using the `networking.k8s.io/v1beta1`...

  * Kube-Proxy now defaults to an iptables-based proxy. If the --proxy-mode flag is
specified while starting kube-proxy (‘userspace’ or ‘iptables’), the flag value
will be respected. If the flag value is not specified, the kube-proxy respects
the Node object annotation: ‘net.beta.kubernetes.io/proxy-mode’. If the
annotation is not specified, then ‘iptables’ mode is the default. If kube-proxy

### Node Components
* **[stable]** Init containers have graduated to GA and now appear as a field.
  The beta annotation value will still be respected and overrides the field
  value.
* Kubelet Container Runtime Interface (CRI) support
  - **[beta]** The Docker-CRI implementation is enabled by default in kubelet.
    You can disable it by --enable-cri=false. See

- New "dry_run" metric label (indicating the value of the dryRun query parameter) has been added into the metrics:
  * apiserver_request_total
  * apiserver_request_duration_seconds  

  - `PriorityLevelConfiguration`: the `.spec.limited.nominalConcurrencyShares` field defaults to `30` only if the field is omitted (v1beta3 also defaulted an explicit `0` value to `30`). Specifying an explicit `0` value is not allowed in the `v1` version in v1.29 to ensure compatibility with `v1.28` API servers. In `v1.30`, explicit `0` values will be allowed in this field in the `v1` API.

...

* Automated cherry pick of [#49259](https://github.com/kubernetes/kubernetes/pull/49259): update json-patch to fix nil value issue when creating mergepatch ([#59324](https://github.com/kubernetes/kubernetes/pull/59324), [@yue9944882](https://github.com/yue9944882))

- Kubeadm: removed the usage of the `--container-runtime=remote` flag for the kubelet during kubeadm init/join/upgrade. The flag value `remote` had been the only possible value since `dockershim` was removed from the kubelet. ([#112000](https://github.com/kubernetes/kubernetes/pull/112000), [@pacoxu](https://github.com/pacoxu))