HP XP7 Storage - Manual (Page 108)

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 DC cascade configuration ” (page 108)
•
“Recovery for 3 Cnt Ac-J Z/Cnt Ac-S Z DC multi-target configuration ” (page 108)
•
“Recovery in a delta resync configuration” (page 110)
Use RAID Manager to perform all procedures.
Recovery for 3 Cnt Ac-J Z/Cnt Ac-S 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 local site of a 3DC cascade configuration. The local
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 141) for information and illustrations on the configuration
covered in this procedure.
Procedure 38 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 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 local site only — see “Recovering from local site failure ” (page 108) .
•
For failure in the local and Continuous Access Synchronous Z intermediate sites — see
“Recovering from local and remote site failure (3DC multi-target)” (page 110)
See “3DC multi-target configuration ” (page 143) for information and illustrations on the configuration
covered in this procedure.
Recovering from local site failure
Host operations are transferred to the secondary volume in the intermediate site when disaster or
failure occurs in the local site in a 3DC multi-target configuration. Replication occurs from the
intermediate site to the local site. Alternatively, a temporary Cnt Ac-J Z system can be set up.
Meanwhile, you correct the failure at the local site, then transfer host operations back to it and set
up a 3DC configuration.
Procedure 39 To recover a local 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.
Running the YKRESYNC REVERSE results in one of the following conditions:
•
The original copy flow of the primary-remote site pair reverses and flows from the
primary-remote secondary volume to the primary volume.
•
The original copy flow does not reverse because of failure in the local site or data path.
108 Cnt Ac-J Z disaster recovery operations