that need to run prior to the network being ready.
* **Enhance Kubelet QoS**:
  * Pods are placed under a new cgroup hierarchy by default. This feature requires
    draining and restarting the node as part of upgrades. To opt-out set
    `--cgroups-per-qos=false`.
  * If `kube-reserved` and/or `system-reserved` are specified, node allocatable

- The calculation of pod UIDs for static pods has changed to ensure each static pod gets a unique value - this will cause all static pod containers to be recreated/restarted if an in-place kubelet upgrade from 1.20 to 1.21 is performed. Note that draining pods before upgrading the kubelet across minor versions is the supported upgrade path. ([#87461](https://github.com/kubernetes/kubernetes/pull/87461), [@bboreham](https://github.com/bboreham)) [SIG Node]

  * Support node port health check ([#43585](https://github.com/kubernetes/kubernetes/pull/43585), [@foolusion](https://github.com/foolusion))

  * Support for ELB tagging by users ([#45932](https://github.com/kubernetes/kubernetes/pull/45932), [@lpabon](https://github.com/lpabon))

* Azure:

- [Kube-proxy]: Implemented connection draining for terminating nodes. ([#116470](https://github.com/kubernetes/kubernetes/pull/116470), [@alexanderConstantinescu](https://github.com/alexanderConstantinescu))

- Upgraded `go-jose` to `v2.6.0` ([#115893](https://github.com/kubernetes/kubernetes/pull/115893), [@mgoltzsche](https://github.com/mgoltzsche))

- Applying fix for not deleting existing public IP when a service is deleted in Azure. ([#100694](https://github.com/kubernetes/kubernetes/pull/100694), [@nilo19](https://github.com/nilo19))
- Applying fix for not tagging static public IP. ([#101752](https://github.com/kubernetes/kubernetes/pull/101752), [@nilo19](https://github.com/nilo19))

- Fixed an issue related to not draining all the pods in a namespace when an empty selector, i.e., "{}," is specified in a Pod Disruption Budget (PDB). ([#119732](https://github.com/kubernetes/kubernetes/pull/119732), [@sairameshv](https://github.com/sairameshv))

* aws: Support for ELB tagging by users ([#45932](https://github.com/kubernetes/kubernetes/pull/45932), [@lpabon](https://github.com/lpabon))

# v1.18.0-alpha.4

[Documentation](https://docs.k8s.io)

## Important note about manual tag

Due to a [tagging bug in our Release Engineering tooling](https://github.com/kubernetes/release/issues/1080) during `v1.18.0-alpha.3`, we needed to push a manual tag (`v1.18.0-alpha.4`).

- Fix: not tagging static public IP ([#101752](https://github.com/kubernetes/kubernetes/pull/101752), [@nilo19](https://github.com/nilo19)) [SIG Cloud Provider]