Retype In-use Ceph > Ceph doesn't actually retype the volume

Issue

• When trying to retype a Ceph volume from one backend to another, such as SAS to NVME. Any volumes that are in-use wont throw immediate errors, but they don't get retyped. Rather, they just show migration_status: error

$ cinder show my_vol
+--------------------------------+------------------------------------------------------------------+
| Property                       | Value                                                            |
+--------------------------------+------------------------------------------------------------------+
| attached_servers               | ['be23603f-783a1-37ac-b548-1be54f718244']                         |
[...]
| migration_status               | error