* Version-guard Kubectl client Guestbook application test against deployments ([#24478](https://github.com/kubernetes/kubernetes/pull/24478), [@ihmccreery](https://github.com/ihmccreery))
* Fix goroutine leak in ssh-tunnel healthcheck. ([#24487](https://github.com/kubernetes/kubernetes/pull/24487), [@cjcullen](https://github.com/cjcullen))

* kube-apiserver now drops unneeded path information if an older version of Windows kubectl sends it. ([#44585](https://github.com/kubernetes/kubernetes/pull/44585), [@mml](https://github.com/mml))
* Fix for kube-proxy healthcheck handling an update that simultaneously removes one port and adds another. ([#44365](https://github.com/kubernetes/kubernetes/pull/44365), [@MrHohn](https://github.com/MrHohn))

* It is now possible to override the healthcheck parameters for AWS ELBs via annotations on the corresponding service. The new annotations are `healthy-threshold`, `unhealthy-threshold`, `timeout`, `interval` (all prefixed with `service.beta.kubernetes.io/aws-load-balancer-healthcheck-`) ([#56024](https://github.com/kubernetes/kubernetes/pull/56024), [@dimpavloff](https://github.com/dimpavloff))

* Fix panic in ControllerManager on GCE when it has a problem with creating external loadbalancer healthcheck ([#52646](https://github.com/kubernetes/kubernetes/pull/52646), [@gmarek](https://github.com/gmarek))

- Fixed a bug that on k8s nodes, when the policy of INPUT chain in filter table is not ACCEPT, healthcheck nodeport would not work.
  Added iptables rules to allow healthcheck nodeport traffic. ([#97824](https://github.com/kubernetes/kubernetes/pull/97824), [@hanlins](https://github.com/hanlins)) [SIG Network]

* GCE: provide an option to disable docker's live-restore on COS/ubuntu ([#55260](https://github.com/kubernetes/kubernetes/pull/55260), [@yujuhong](https://github.com/yujuhong))
* Fix kube-proxy hang due to panic when requesting a closed healthcheck. ([#46450](https://github.com/kubernetes/kubernetes/pull/46450), [@MrHohn](https://github.com/MrHohn))

* Allow setting the Host header in a httpGet probe ([#24292](https://github.com/kubernetes/kubernetes/pull/24292), [@errm](https://github.com/errm))
* Fix goroutine leak in ssh-tunnel healthcheck. ([#24487](https://github.com/kubernetes/kubernetes/pull/24487), [@cjcullen](https://github.com/cjcullen))

  unsupported.' ([#119346](https://github.com/kubernetes/kubernetes/pull/119346), [@chendave](https://github.com/chendave))
- '`kubeadm`: removed `system:masters` organization from `etcd/healthcheck-client`
  certificate.' ([#119859](https://github.com/kubernetes/kubernetes/pull/119859), [@SataQiu](https://github.com/SataQiu))

### API Change

* Added --log-facility flag to enhance dnsmasq logging ([#32422](https://github.com/kubernetes/kubernetes/pull/32422), [@MrHohn](https://github.com/MrHohn))
* Split dns healthcheck into two different urls ([#32406](https://github.com/kubernetes/kubernetes/pull/32406), [@MrHohn](https://github.com/MrHohn))