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 acquiesced 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.

Before a device group can be placed in maintenance state, all access to its devices must be stopped, and all dependent file systems must be unmounted.

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/Solaris Volume Manager:

   # metaset -C take -f -s diskset

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   Caution –

   If you are taking ownership of a Solstice DiskSuite/Solaris Volume Manager 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.

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   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.

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   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.

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   • For Solstice DiskSuite/Solaris Volume Manager:

     # 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 node

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/Solaris Volume Manager:
  # 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/Solaris Volume Manager:
  # 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