HP XP P9500 Storage - Manual (Page 107)

Recovery procedures when Cnt Ac-J Z P-VOLs and S-VOLs are shared with Continuous Access
Synchronous Z or with other Cnt Ac-J Z pairs can be more complex than general procedures.
The following topics provide recovery procedures for resuming host operations at a backup site
and then restoring the original system and configurations.
•
“Recovery for 3 Cnt Ac-J Z/Cnt Ac-S Z or 3 Cnt Ac-J Z DC cascade configuration ” (page 107)
•
“Recovery for 3 Cnt Ac-J Z/Cnt Ac-S Z or 3 Cnt Ac-J Z DC multi-target configuration ” (page 107)
•
“Recovery in a delta resync configuration” (page 109)
Use RAID Manager to perform all procedures.
Recovery for 3 Cnt Ac-J Z/Cnt Ac-S Z or 3 Cnt Ac-J Z DC cascade configuration
Host operations are transferred to the Cnt Ac-S Z secondary volume (S-VOL) at the intermediate
site when a disaster or failure occurs in the primary site of a 3DC cascade configuration. The
primary site failure is corrected and brought back online, then either the cascade configuration is
restored or the multi-target configuration is created.
See “3DC cascade configuration ” (page 145) or “3 Cnt Ac-J Z DC cascade configuration” (page 135)
for information and illustrations on the configuration covered in this procedure.
Procedure 30 To recover a 3DC cascade configuration failure
1. Check consistency of the secondary volume in the intermediate site.
2. Run the YKSUSPND REVERSE command on the secondary volume.
3. Start host operations to the secondary volume in the intermediate site.
4. Run the YKRESYNC REVERSE command on the copy groups of the primary-intermediate pair.
This operation reverses the copy direction.
Recovery for 3 Cnt Ac-J Z/Cnt Ac-S Z or 3 Cnt Ac-J Z DC multi-target configuration
The recovery procedure you perform in a 3DC multi-target configuration depends on the location
of the failure:
•
For failure in the primary site only — see “Recovering from primary site failure ” (page 107) .
•
For failure in the primary and Continuous Access Synchronous Z intermediate sites — see
“Recovering from primary and secondary site failure (3DC multi-target)” (page 109)
See “3DC multi-target configuration ” (page 147) or “3 Cnt Ac-J Z DC multi-target configuration”
(page 137) for information and illustrations on the configuration covered in this procedure.
Recovering from primary site failure
For 3 Cnt Ac-J Z DC configurations, recover by starting host operatons to either remote site secondary
volume.
For 3 Cnt Ac-J Z/Cnt Ac-S Z configurations, host operations are transferred to the secondary volume
in the intermediate site when disaster or failure occurs in the primary site in a 3DC multi-target
configuration. Replication occurs from the intermediate site to the primary site. Alternatively, a
temporary Cnt Ac-J Z system can be set up. Meanwhile, you correct the failure at the primary site,
then transfer host operations back to it and set up a 3DC configuration.
Procedure 31 To recover a primary site failure
1. Release the Cnt Ac-J Z pair to the S-VOL by executing the YKRECVER command.
2. Suspend the primary-remote site pair by executing the YKSUSPND REVERSE command. This
stops copy operations.
3. Start host operations to the remote site secondary volume.
4. Reverse the copy flow of the primary-remote site pair by executing the YKRESYNC REVERSE
command.
Recovery for 3 Cnt Ac-J Z/Cnt Ac-S Z data centers and 3 Cnt Ac-J Z data centers 107