3.3.14 How to Change Disk Device Properties

The method for establishing the primary ownership of a disk device group is based on the setting of an ownership preference attribute called preferenced. If the attribute is not set, the primary owner of an otherwise unowned disk device group is the first node that attempts to access a disk in that group. However, if this attribute is set, you must specify the preferred order in which nodes attempt to establish ownership.

If you disable the preferenced attribute, then the failback attribute is also automatically disabled. However, if you attempt to enable or re-enable the preferenced attribute, you have the choice of enabling or disabling the failback attribute.

If the preferenced attribute is either enabled or re-enabled, you are required to re-establish the order of nodes in the primary ownership preference list.

This procedure uses scsetup(1M) to set or unset the preferenced attribute and the failback attribute for Solstice DiskSuite or VxVM disk device groups.

To run this procedure, you need the name of the disk device group for which you are changing attribute values.

1. Become superuser on a node of the cluster.

2. Enter the scsetup(1M) utility

   The Main Menu appears.

   # scsetup

3. To work with disk device groups, enter 3 (Device groups and volumes).

   The Device Groups Menu appears.

4. To change a device group property, enter 6 (Change key properties of a VxVM or Solstice DiskSuite device group).

   Follow the instructions to set the preferenced and failback options for a device group.

5. Verify that the disk device group attributes have been changed.

   Look for the device group information displayed by the following command.

   # scconf -p

3.3.14.1 Example--Changing Disk Device Group Properties

The following example shows the scconf command generated by scsetup when it sets the attribute values for a disk device group (dg-schost-1).

# scconf -c -D name=dg-schost-1,nodelist=phys-schost-1:phys-schost-2,\
preferenced=true,failback=enabled
# scconf -p
Device group name:                             dg-schost-1
   Device type:                                SDS
   Failback enabled:                           yes
   Node preference list:                       phys-schost-1, phys-schost-2
   Diskset name:                               dg-schost-1