agent) that runs one, and only one, pod per node.
     * TLS and L7 support (Ingress API (Beta) in the Extensions API group): Kubernetes
is now easier to integrate into custom networking environments by supporting
TLS for secure communication and L7 http-based traffic routing.
     * Graceful Node Shutdown (aka drain) - The new “kubectl drain” command gracefully
evicts pods from nodes in preparation for disruptive operations like kernel

```
kubectl --namespace=federation get secret federation-apiserver-secret -o json | sed 's/federation-apiserver-secret/federation-apiserver-kubeconfig/g' | kubectl create -f -
# optionally, remove the old secret
kubectl delete secret --namespace=federation federation-apiserver-secret
```

- The cloud config for Azure cloud provider can now be initialized from Kubernetes secret azure-cloud-provider in kube-system namespace
    - the secret is a serialized version of `azure.json` file with key cloud-config. And the secret name is azure-cloud-provider.
    - A new option cloudConfigType has been added to the cloud-config file. Supported values are: `file`, `secret` and `merge` (`merge` is the default value).

* The kubelet API is now secured, only cluster admins are allowed to access it.
* Insecure access to the API Server over `localhost:8080` is now disabled.
* The control plane components now talk securely to each other. The API Server talks securely to the kubelets in the cluster.

## Kubefed

* Deprecate the `--secret-name` flag from `kubefed join`, instead generating the secret name arbitrarily. ([#42513](https://github.com/kubernetes/kubernetes/pull/42513), [@perotinus](https://github.com/perotinus))


### **Kubernetes API**
#### User Provided Extensions

- Scheduler skips NodeAffinity Score plugin when NodeAffinity Score plugin has nothing to do with a Pod.

* Disabling swagger ui by default on apiserver. Adding a flag that can enable it ([#23025](https://github.com/kubernetes/kubernetes/pull/23025), [@nikhiljindal](https://github.com/nikhiljindal))
* restore ability to run against secured etcd ([#21535](https://github.com/kubernetes/kubernetes/pull/21535), [@AdoHe](https://github.com/AdoHe))

### Other notable changes

* kubelet: resolved hang/timeout issues when running large numbers of pods with unique configmap/secret references by reverting to 1.11 configmap/secret lookup behavior ([#74755](https://github.com/kubernetes/kubernetes/pull/74755), [@liggitt](https://github.com/liggitt))

- Use of secret-based service account tokens now adds an `authentication.k8s.io/legacy-token-autogenerated-secret` or `authentication.k8s.io/legacy-token-manual-secret` audit annotation containing the name of the secret used. ([#118598](https://github.com/kubernetes/kubernetes/pull/118598), [@yuanchen8911](https://github.com/yuanchen8911)) [SIG Auth, Instrumentation...

- Fixed file permission issues that happened during update of Secret/ConfigMap/projected volume when fsGroup is used. The problem caused a race condition where application gets intermittent permission denied error when reading files that were just updated, before the correct permissions were applied. ([#114728](ht...