Unmirroring a Device

Disk mirroring is automatically deactivated when one of the two physical devices fails.

When a read or write to a mirrored device is unsuccessful, SAP ASE prints error messages. SAP ASE continues to run, unmirrored. You must remirror the disk to restart mirroring.

Use the disk unmirror command to stop the mirroring process during hardware maintenance:
disk unmirror 
     name = "device_name" 
     [, side = { "primary" | secondary }] 
     [, mode = { retain | remove }]