- OpenStack Cinder CSI migration is on by default, Clinder CSI driver must be installed on clusters on OpenStack for Cinder volumes to work. ([#98538](https://github.com/kubernetes/kubernetes/pull/98538), [@dims](https://github.com/dims)) [SIG Storage]

### **OpenStack**

*   OpenStack Cinder support has been improved:
    *   Cinder version detection now works properly. ([#53115](https://github.com/kubernetes/kubernetes/pull/53115),[ @FengyunPan](https://github.com/FengyunPan))

* PVC may not be synced to controller local cache in time if PV is bound by external PV binder (e.g. kube-scheduler), double check if PVC is not found to prevent reclaiming PV wrongly. ([#67062](https://github.com/kubernetes/kubernetes/pull/67062), [@cofyc](https://github.com/cofyc))

- Promote CSIMigrationOpenStack to Beta (off by default since it requires installation of the OpenStack Cinder CSI Driver. The in-tree AWS OpenStack Cinder driver "kubernetes.io/cinder" was deprecated in 1.16 and will be removed in 1.20. Users should enable CSIMigration + CSIMigrationOpenStack features and install the OpenStack Cinder CSI Driver (https://github.com/kubernetes/cloud-provider-openstack) to avoid disruption to existing Pod and PVC objects at that time....

* Make volume usage metrics available for Cinder ([#62668](https://github.com/kubernetes/kubernetes/pull/62668), [@zetaab](https://github.com/zetaab))

conjunction with SIG Cloud Provider, is focusing on moving internal APIs that the OpenStack (and other providers) depends upon to staging to guarantee API stability. This work also included abstracting the in-tree Cinder API and refactoring code to the external Cinder provider to remove additional Cinder volume provider code.

Additional work was also done to implement an OpenStack driver for the Cluster API effort lead by SIG Cluster Lifecycle. For the external Cloud-Provider-OpenStack code, the...

- Fix filtering of server status.
- Fix resizing PVC of Cinder volume.
- Disable load balancer configuration if it is not defined in cloud config.
- Add support for node shutdown taint.

The external provider includes all of the above with the additional fixes and features:
- Fix bug to prevent allocation of existing floating IP.
- Fix Cinder authentication bug when OS_DOMAIN_NAME not specified.

- New flag `--show-hidden-metrics-for-version` in kube-apiserver can be used to show all hidden metrics that deprecated in the previous minor release. ([#84292](https://github.com/kubernetes/kubernetes/pull/84292), [@RainbowMango](https://github.com/RainbowMango))

* Updates Cinder AttachDisk operation to be more reliable by delegating Detaches to volume manager. ([#50042](https://github.com/kubernetes/kubernetes/pull/50042), [@jingxu97](https://github.com/jingxu97))

- StatefulSet pods now have the pod index set as a pod label `statefulset.kubernetes.io/pod-index`. ([#119232](https://github.com/kubernetes/kubernetes/pull/119232), [@danielvegamyhre](https://github.com/danielvegamyhre)) [SIG Apps]