/** The key of the configuration. e.g. boost */
    String INDEX_ADMIN_FLOAT_FIELDS = "index.admin.float.fields";

    /** The key of the configuration. e.g.  */
    String INDEX_ADMIN_DOUBLE_FIELDS = "index.admin.double.fields";

    /** The key of the configuration. e.g. url,title,role,boost */
    String INDEX_ADMIN_REQUIRED_FIELDS = "index.admin.required.fields";

 - `kubeadm`: a separate "super-admin.conf" file is now deployed. The User in `admin.conf` is now bound to a new RBAC Group `kubeadm:cluster-admins` that has `cluster-admin` `ClusterRole` access. The User in `super-admin.conf` is now bound to the `system:masters` built-in super-powers / break-glass Group that can bypass RBAC. Before this change, the default `admin.conf` was bound to `system:masters` Group, which was undesired. Executing `kubeadm...

  // glusterfs represents a Glusterfs volume that is attached to a host and
  // exposed to the pod. Provisioned by an admin.
  // More info: https://examples.k8s.io/volumes/glusterfs/README.md
  // +optional
  optional GlusterfsPersistentVolumeSource glusterfs = 4;

  // nfs represents an NFS mount on the host. Provisioned by an admin.
  // More info: https://kubernetes.io/docs/concepts/storage/volumes#nfs
  // +optional

## Major updates and release themes

* Kubernetes now supports up to 5,000 nodes via etcd v3, which is enabled by default.
* [Role-based access control (RBAC)](https://kubernetes.io//docs/admin/authorization/rbac) has graduated to beta, and defines secure default roles for control plane, node, and controller components.

### **Security**
#### Admission Control
* [alpha] Add [extensible external admission control](https://kubernetes.io/docs/admin/extensible-admission-controllers/).

#### TLS Bootstrapping
* [alpha] Rotation of the server TLS certificate on the kubelet. See [TLS bootstrapping - approval controller](https://kubernetes.io/docs/admin/kubelet-tls-bootstrapping/#approval-controller).

### Auth

* When using Role-Based Access Control, the "admin", "edit", and "view" roles now have the expected permissions on NetworkPolicy resources, rather than reserving those permissions to only cluster-admin. ([#56650](https://github.com/kubernetes/kubernetes/pull/56650), [@danwinship](https://github.com/danwinship))

A security issue was discovered in Kubernetes where a user that can create pods and persistent volumes on Windows nodes may be able to escalate to admin privileges on those nodes. Kubernetes clusters are only affected if they are using an in-tree storage plugin for Windows nodes.

**Affected Versions**:
  - kubelet >= v1.8.0

**Fixed Versions**:

`system:aggregate-to-edit` role no longer includes write access to the Endpoints API. For new Kubernetes 1.22 clusters, the `edit` and `admin` roles will no longer include that access in newly created Kubernetes 1.22 clusters. This will have no affect on existing clusters upgrading to Kubernetes 1.22. To retain write access to Endpoints in the aggregated `edit` and `admin` roles for newly created 1.22 clusters, refer to https://github.com/kubernetes/website/pull/29025. ([#103704](https://github.com/k...

* Fixes ability for admin/edit/view users to see controller revisions, needed for kubectl rollout commands ([#70699](https://github.com/kubernetes/kubernetes/pull/70699), [@liggitt](https://github.com/liggitt))