3.3.19 How to Put a Disk Device Group in Maintenance State

Putting a device group in maintenance state prevents that device group from automatically being brought online whenever one of its devices is accessed. You should put a device group in maintenance state when completing repair procedures that require that all I/O activity be quiesced until completion of the repair. Putting a device group in maintenance state also helps prevent data lost by ensuring that a disk device group is not brought online on one node while the diskset or disk group is being repaired on another node.

1. Place the device group in maintenance state.

   # scswitch -m -D disk-device-group

2. If the repair procedure being performed requires ownership of a diskset or disk group, manually import that diskset or disk group.

   • For Solstice DiskSuite:

     # metaset -C take -f -s diskset

   ---

   Caution -

   If you are taking ownership of an SDS diskset, the metaset -C take command must be used when the device group is in maintenance state. Using metaset -t will bring the device group online as part of taking ownership. If you are importing a VxVM disk group, the -t flag must be used when importing the disk group. This prevents the disk group from automatically being imported if this node is rebooted.

   ---

   • For VERITAS Volume Manager:

     # vxdg -t import disk-group-name

3. Complete whatever repair procedure you need to perform.

4. Release ownership of the diskset or disk group.

   ---

   Caution -

   Before taking the disk device group out of maintenance state, you must release ownership of the diskset or disk group. Failure to do so may result in data loss.

   ---

   • For Solstice DiskSuite:

     # metaset -C release -s diskset

   • For VERITAS Volume Manager:

     # vxdg deport disk-group-name

5. Bring the disk device group online.

   # scswitch -z -D disk-device-group -h nodelist

3.3.19.1 Example--Putting a Disk Device Group in Maintenance State

This example shows how to put disk device group dg-schost-1 into maintenance state, and remove the disk device group from maintenance state.

[Place the disk device group in maintenance state.]
# scswitch -m -D dg-schost-1
 
[If needed, manually import the diskset or disk group.]
For Solstice DiskSuite:
  # metaset -C take -f -s dg-schost-1
For VERITAS Volume Manager:
  # vxdg -t import dg1
  
[Complete all necessary repair procedures.]
  
[Release ownership.]
For Solstice DiskSuite:
  # metaset -C release -s dg-schost-1
For VERITAS Volume Manager:
  # vxdg deport dg1
  
[Bring the disk device group online.]
# scswitch -z -D dg-schost-1 -h phys-schost-1