HP StorageWorks SAN Virtualization Services Platform Best Practices Guide (5697-0935, May 2011)

Prepare destination site group
1. Delete synchronous mirrors to prepare for migration (the synchronous mirror cannot be
migrated). Delete the synchronous mirrors in the following order or you may lose host
presentation:
a. Detach the second task.
b. Delete the synchronous mirror group.
2. Delete SVSP virtual disks on the second site (former second task) to create pool space.
3. Delete the pool (if there are still virtual disk segments, the deletion will not be possible). Verify
that all back-end LUs display "configured=No" in the GUI.
4. Reorganize the back-end LUs.
5. Reboot the DPMs.
a. Failover the SVSP virtual disks to the other DPM (right-click the DPM, and select failover
all).
NOTE: Ensure all application servers have MPIO installed. Otherwise they will lose
access to their virtual disks.
b. Verify that the DPM does not have any active virtual disks.
c. Reboot the DPM.
d. When the DPM is online, use PuTTY or Telnet and run show debug agentstate to
verify that all paths to the back-end LUs display an OK status.
e. Repeat steps a through d for the other DPMs.
6. Re-create the pool according to the new design (stripe sets first, then the pool from the stripe
sets).
Migrate to the destination site pool
1. Migrate the virtual disks from the first site (former first task with host presentations) to the second
site pool that has the new design.
• Ensure that you have at least 20% of the largest virtual disk free in the source pool,
otherwise migration will not be possible. You might need to temporarily add an additional
back-end LU to the pool.
• HP recommends adding prefixes to the names of groups, tasks, and virtual disks. For
example, -g_ for groups, -t_ for tasks, and -a_ for auxiliary virtual disks (the auxiliary
virtual disks will be deleted afterwards). A group example may be -g_host1Database1.
2. Once all migration groups are finished (they are automatically deleted once they are complete),
verify that all migrated virtual disks are in the new pool and have host presentation.
3. Verify that all virtual disks in the original pool (the migration source site) have the auxiliary
name (with host presentation = none).
Prepare the source site pool
1. Delete auxiliary virtual disks to create source pool capacity (be careful because SVSP does
not check if virtual disks have host presentation). Make sure you delete auxiliary virtual disks
only.
2. Delete the pool (if there are still virtual disk segments, the deletion cannot happen). Check
that all back-end LUs display "configured=No" in the GUI.
3. Reorganize the back-end LUs.
4. Reboot the DPMs.
44 Synchronous mirroring