// +optional
  optional string user = 5;

  // keyring is the path to key ring for RBDUser.
  // Default is /etc/ceph/keyring.
  // More info: https://examples.k8s.io/volumes/rbd/README.md#how-to-use-it
  // +optional
  optional string keyring = 6;

  // secretRef is name of the authentication secret for RBDUser. If provided
  // overrides keyring.
  // Default is nil.

## Changelog since v1.10.1

### Other notable changes

* kubeadm upgrade no longer races leading to unexpected upgrade behavior on pod restarts ([#62655](https://github.com/kubernetes/kubernetes/pull/62655), [@stealthybox](https://github.com/stealthybox))

- Ceph RBD volume plugin now does not use any keyring (`/etc/ceph/ceph.client.lvs01cinder.keyring`, `/etc/ceph/ceph.keyring`, `/etc/ceph/keyring`, `/etc/ceph/keyring.bin`) for authentication. Ceph user credentials must be provided in PersistentVolume objects and referred Secrets. ([#75588](https://github.com/kubernetes/kubernetes/pull/75588), [@smileusd]...

  * OOM parser uses kmsg
  * Add hugepages support
  * Add CRI-O support

* Sharing a PID namespace between containers in a pod is disabled by default in version 1.8. To enable for a node, use the `--docker-disable-shared-pid=false` kubelet flag. Be aware that PID namespace sharing requires Docker version greater than or equal to 1.13.1.

* Fix issues related to the eviction manager.

- Added warnings to the Services API. Kubernetes now warns for Services in the case of:
  - IPv4 addresses with leading zeros
  - IPv6 address in non-canonical format (RFC 5952) ([#114505](https://github.com/kubernetes/kubernetes/pull/114505), [@aojea](https://github.com/aojea))

* Fixed a bug in the apiserver storage that could cause just-added finalizers to be ignored on an immediately following delete request, leading to premature deletion. ([#77619](https://github.com/kubernetes/kubernetes/pull/77619), [@caesarxuchao](https://github.com/caesarxuchao))

    * "volume.alpha.kubernetes.io/storage-class" does not have any special meaning. A default storage class
    * and  DefaultStorageClass admission plugin can be used to preserve similar behavior of Kubernetes cluster,
    * see https://kubernetes.io/docs/user-guide/persistent-volumes/#class-1 for details.

- Fix the code is leaking the defaulting between unrelated pod instances. ([#103284](https://github.com/kubernetes/kubernetes/pull/103284), [@kebe7jun](https://github.com/kebe7jun)) [SIG CLI]

- The underlying format of the `CPUManager` state file has changed. Upgrades should be seamless, but any third-party tools that rely on reading the previous format need to be updated. ([#84462](https://github.com/kubernetes/kubernetes/pull/84462), [@klueska](https://github.com/klueska)) [SIG Node and Testing]

- Removed leading zeros from the etcd member ID in kubeadm log messages. ([#117919](https://github.com/kubernetes/kubernetes/pull/117919), [@dlipovetsky](https://github.com/dlipovetsky)) [SIG Cluster Lifecycle]