ISSUE
When you attempt to perform a restore to Xenserver, you are presented with the error failed to restore disk. You may see this in the BACKUP HISTORY/Report logs for the failed job:
User...........: Supervisor (override is enabled)
Files to restore: All files
Client Name....: localhost.localdomain [127.0.0.1]
Starting Dir...: metadata.xml:/
Exit Code......: 255
Exit Status....: Failed
----- XProtect Messages ----
failed to restore disk
----- End XProtect Messages ----
No client messages due to log level 2
RESOLUTION
Please review the XProtect Logs. If you find this entry
HA_OPERATION_WOULD_BREAK_FAILOVER_PLAN
- ...please disable High Availability on the Xenserver.
- Perform your restore.
- Once the restore has completed, you can re-enable the HA (but ensure that the Unitrends Backup VM is never part HA.).
CAUSE
The Citrix XenServer Management API states for HA_OPERATION_WOULD_BREAK_FAILOVER_PLAN:
"This operation cannot be performed because it would invalidate VM failover planning such that the system would be unable to guarantee to restart protected VMs after a Host failure."