Apple Xsan 2 (Third Edition) - Manual (Page 88)

Setting Controller Failover Priority
When the primary metadata controller for a volume fails, Xsan uses the failover
priorities of the available standby controllers to decide which one to switch to.
Different volumes can be hosted by different controllers, and you can choose a failover
priority for each volume.
To set a metadata controller’s failover priority:
1 Open Xsan Admin, select Volumes in the SAN Assets list, and select a volume in the list.
2 Choose Edit Failover Priority from the Action (gear) pop-up menu.
3 Drag metadata controllers up or down in the list that appears.
The closer a controller is to the top of the list, the more likely it is that it will host the
volume.
4 Click OK.
Switching to a Standby Controller
You can use Xsan Admin to force an active metadata controller to turn over control of
a volume to a standby controller.
To switch a volume to a standby metadata controller:
1 Open Xsan Admin and select Volumes in the SAN Assets list.
2 Select the volume in the list and choose “Force failover” from the Action (gear) pop-up
menu.
From the Command Line
You can also switch a volume to a standby metadata controller using the
cvadmin
fail command in Terminal. For more information, see the cvadmin man page or
“Viewing or Changing Volume and Storage Pool Settings (cvadmin)” on page 111.
88 Chapter 6 Managing Metadata Controllers