HP StorageWorks SAN Virtualization Services Platform administrator guide (5697-0109, July 2009)

3. Detach the tasks coming into the SVSP domain.
4. Assign the host permission to use the recovery virtual disks. You can do either of the following:
a. Right-click the specific DR element that you want to recover, and select Manage > Add Host
Permission to assign permission to a host to use the DR element. The host will then use the
most recent PiT available on that DR element. There is a chance, however, that the application
will not be able to use the PiT as it is. This is because mirror standard PiTs are taken at times
that are asynchronous to the application state. If this is the case and the application cannot
use the PiT, you will need to run some application-specific recovery procedures to bring the
application online. Any modifications that such utilities perform will be written to the most
recent PiT. If this procedure fails, you still have the option to roll back to earlier PiTs or user
PiTs, if available, and try once again to recover. Once recovered, you may start deleting
the older PiTs that are on that element, unless you want to maintain them for a future merge
with the main site, after recovery.
b. Test the ability to recover from every PiT before assigning presentations to production hosts,
and without modifying any PiT while testing. To test each PiT for this purpose, create a
snapshot on the PiT, and present it to the host running the application. If the application
works with the snapshot, you know that the host can also work directly with the PiT from
which the snapshot was created. Any modification that the application writes to the snapshot
during the validation process does not modify the PiT. If your recovery attempt fails, you can
delete the snapshot, create a new one, and start again. After you have found the best PiT
for recovery and verified the steps that you need to perform on the application, you can
delete the snapshot. You should then roll back to the PiT you want to use, and then expose
the DR element with all its remaining PiTs to a host. To expose the DR element to a host, right
click the DR element and select Manage > Add Host Permission. Once recovered, you may
start deleting the older PiTs that are on the DR element, unless you want to maintain them
for a future merge with the main site, once recovered.
When you have rebuilt the main site, you can run the following procedure to fail back to the new
main site without losing production data.
To restore production to a rebuilt main site:
1. Reconnect the SVSP domains.
2. Connect to the DR site's SVSP domain and create new async mirror groups and tasks to mirror
the production virtual disks on the DR site to new destination virtual disks on the new main site.
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