* Added a way to pass extra arguments to etcd. The these extra arguments can be used to adjust runtime configuration like heartbeat interval etc. ([#63961](https://github.com/kubernetes/kubernetes/pull/63961), [@mborsz](https://github.com/mborsz))

* Resolves a bug that prevented sending a multi-version custom resource to an admission webhook. ([#79495](https://github.com/kubernetes/kubernetes/pull/79495), [@liggitt](https://github.com/liggitt))
* Pass-through volume MountOptions to global mount (NodeStageVolume) on the node for CSI ([#80191](https://github.com/kubernetes/kubernetes/pull/80191), [@davidz627](https://github.com/davidz627))

- E2e.test: removed the  `--viper-config` flag. If you were previously using this to pass flags to `e2e.test` via a file, you will need to pass them directly on the command line, e.g. `e2e.test --e2e-output-dir`. ([#102598](https://github.com/kubernetes/kubernetes/pull/102598), [@dims](https://github.com/dims))

- hyperkube: Use debian-hyperkube-base@v1.1.1...

- Client-go impersonation config can specify a UID to pass impersonated uid information through in requests. ([#104483](https://github.com/kubernetes/kubernetes/pull/104483), [@margocrawf](https://github.com/margocrawf))

- Pass additional flags to subpath mount to avoid flakes in certain conditions ([#104348](https://github.com/kubernetes/kubernetes/pull/104348), [@mauriciopoppe](https://github.com/mauriciopoppe)) [SIG Storage]

## Known Issues for v1.5.1

- `hack/local-up-cluster.sh` script times out waiting for apiserver to answer, see [#38847](https://github.com/kubernetes/kubernetes/issues/38847).
  To workaround this, modify the script to pass `--anonymous-auth=true` to `sudo -E "${GO_OUT}/hyperkube" apiserver ...` when starting `kube-apiserver`.

# v1.5.0

[Documentation](https://docs.k8s.io) & [Examples](https://releases.k8s.io/release-1.5/examples)

`kube-system/kubelet-config` naming scheme for the kubelet ConfigMap and RBAC rules, instead of the legacy `kubelet-config-x.yy` naming. 2) during upgrade, kubeadm will only write the new scheme ConfigMap and RBAC objects. To disable the feature you can pass `UnversionedKubeletConfigMap: false` in the kubeadm config for new clusters. For upgrade on existing clusters you can also override the behavior by patching the ClusterConfiguration object in `kube-system/kubeadm-config`. More details in the associated...

- Pass additional flags to subpath mount to avoid flakes in certain conditions ([#104340](https://github.com/kubernetes/kubernetes/pull/104340), [@mauriciopoppe](https://github.com/mauriciopoppe)) [SIG Node, Storage and Windows]

- Kubeadm: pass the host OS environment variables when executing "crictl" during image pulls. This fixes a bug where *PROXY environment variables did not affect crictl's internet connectivity. ([#110134](https://github.com/kubernetes/kubernetes/pull/110134), [@mk...