Unable to delete SnapCenter resource group due to backup having mounts

Applies to

SnapCenter Server

Issue

When attempting to delete a resource group in SnapCenter, the following error is displayed, even if there are no active mounts:

'Backup Deletion Failed: Backup <snapshot name> has mounts, cannot be deleted, unmount and retry again'

This is due to the SnapCenter Repository (NSM MySQL database) having stale entries referencing a backup mount. This can be caused when a SnapCenter created clone is removed manually from the storage system without the use of SnapCenter.

The SnapManager web log displays the following:

2018-06-19T09:29:30.7396260-05:00 DEBUG SnapManagerWeb PID=[10592] TID=[148] Backup <VM_backup_At_#time_#hostname_#datetime> has mounts,cannot be deleted, unmount and retry again.
2018-06-19T09:29:30.7552520-05:00 ERROR SnapManagerWeb PID=[10592] TID=[148] ErrorCode (-1), ErrorMessage (Backup <VM_backup_At_#time_#hostname_#datetime> has mounts,cannot be deleted, unmount and retry again.)
2018-06-19T09:29:30.7552520-05:00 DEBUG SnapManagerWeb PID=[10592] TID=[148] DeleteMainBackups End.
2018-06-19T09:29:30.7552520-05:00 DEBUG SnapManagerWeb PID=[10592] TID=[148] DeleteBackup End.
2018-06-19T09:29:30.7552520-05:00 DEBUG SnapManagerWeb PID=[10592] TID=[148] Backup Deletion Failed: Backup <VM_backup_At_#time_#hostname_#datetime> has mounts,cannot be deleted, unmount and retry again.