- The deprecated `--etcd-quorum-read` flag has been removed. Quorum reads are now always enabled when fetching data from etcd. Remove the `--etcd-quorum-read` flag from kube-apiserver invocations before upgrading.
- kube-controller-manager
  - The deprecated `--insecure-experimental-approve-all-kubelet-csrs-for-group` flag has been removed.

  * Filter out IPV6 node addresses. ([#45181](https://github.com/kubernetes/kubernetes/pull/45181), [@BaluDontu](https://github.com/BaluDontu))

  * Fix fetching of VM UUID on Ubuntu 16.04 and Fedora. ([#45311](https://github.com/kubernetes/kubernetes/pull/45311), [@divyenpatel](https://github.com/divyenpatel))


#### Cluster Provisioning
* Juju:

stopped before performing a rollback. ([#59298](https://github.com/kubernetes/kubernetes/pull/59298), [@jpbetz](https://github.com/jpbetz))

* The `meta.k8s.io/v1alpha1` objects for retrieving tabular responses from the server (`Table`) or fetching just the `ObjectMeta` for an object (as `PartialObjectMetadata`) are now beta as part of `meta.k8s.io/v1beta1` and configurations must be changed to use the new API.  Clients may request alternate representations of normal Kubernetes objects by passing...

- Fix route conflicted operations when updating multiple routes together ([#88209](https://github.com/kubernetes/kubernetes/pull/88209), [@feiskyer](https://github.com/feiskyer)) [SIG Cloud Provider]

* vSphere cloud provider: Fix fetching of VM UUID on Ubuntu 16.04 and Fedora. ([#45311](https://github.com/kubernetes/kubernetes/pull/45311), [@divyenpatel](https://github.com/divyenpatel))



# v1.6.4

- Add `--kubernetes-version` to `kubeadm init phase certs ca` and `kubeadm init phase kubeconfig` ([#80115](https://github.com/kubernetes/kubernetes/pull/80115), [@gyuho](https://github.com/gyuho))
- kubeadm: support fetching configuration from the original cluster for `upgrade diff` ([#80025](https://github.com/kubernetes/kubernetes/pull/80025), [@SataQiu](https://github.com/SataQiu))

- Removed the deprecated `azureFile` in-tree storage plugin. ([#118236](https://github.com/kubernetes/kubernetes/pull/118236), [@andyzhangx](https://github.com/andyzhangx))
- Revised `OpenAPI v2` fetching for CustomResourceDefinitions. CRDs are now aggregated lazily,
  which improves resource usage during installation of many CRDs. As a result, the first request

- The calculations for Pod topology spread skew now exclude nodes that
  don't match the node affinity/selector. This may lead to unschedulable pods if you previously had pods
  matching the spreading selector on those excluded nodes (not matching the node affinity/selector),
  especially when the `topologyKey` is not node-level. Revisit the node affinity and/or pod selector in the

- Fire an event when failing to open `NodePort`. ([#100599](https://github.com/kubernetes/kubernetes/pull/100599), [@masap](https://github.com/masap))
- Fix Azure node public IP fetching issues from instance metadata service when the node is part of standard load balancer backend pool. ([#100690](https://github.com/kubernetes/kubernetes/pull/100690), [@feiskyer](https://github.com/feiskyer)) [SIG Cloud Provider]

### **Instrumentation**

#### **Audit**

*   Adjust batching audit webhook default parameters: increase queue size, batch size, and initial backoff. Add throttling to the batching audit webhook. Default rate limit is 10 QPS. ([#53417](https://github.com/kubernetes/kubernetes/pull/53417),[ @crassirostris](https://github.com/crassirostris))