Switching operations to the secondary site, Transferring operations back to the primary site – HP StorageWorks XP Remote Web Console Software User Manual
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Switching Operations to the Secondary Site
If a disaster or failure occurs at the primary site, the first disaster recovery activity is to use Business
Continuity Manager to switch your operations to the remote backup site.
The basic procedures for switching operations to the remote backup site are as follows:
If you need to perform an IPL of the secondary host system, please delete SIMs and then perform the IPL
before following the procedure below. When the IPL finishes, the secondary data volumes will usually be
varied online. If the secondary volume are not varied online, vary the volumes online.
If you do not need to perform an IPL of the secondary host system, please ensure that the secondary data
volumes are varied online before you follow the procedure below.
1.
Check whether the restore journal group includes a secondary data volume whose pair status is
Pending duplex or Suspend (equivalent to SUSPOP in Business Continuity Manager).
If such a pair exists, consistency in the secondary data volume is dubious, and recovery with
guaranteed consistency is impossible. In this case, if you want to use the secondary data volume,
you must release the pair.
2.
If such a pair does not exist, use Business Continuity Manager to execute the YKSUSPND
REVERSE option on the restore journal group (YKSUSPND is a command for splitting a pair).
If an error occurs, consistency in the secondary data volume is dubious, and recovery with
guaranteed consistency is impossible. In this case, if you want to use the secondary data
volume, you must release the pair.
3.
If no error occurs in step
on page 198, wait until the splitting finishes. When the splitting
finishes, the secondary data volume becomes usable with maintained consistency.
4.
When the splitting finishes, use Business Continuity Manager to execute the YKRESYNC REVERSE
option on the restore journal group (YKRESYNC is a command for restoring a pair). This option
attempts to restore the pair and reverse the primary/secondary relationship.
5.
Check whether there is a pair whose pair status of the restore journal group is Suspend
(equivalent to SWAPPING in Business Continuity Manager).
If such a pair does not exist, the pair is successfully restored and the copy direction is reversed, and
then copying of data from the secondary site to the primary site will start.
6.
If the YKSUSPND command finishes successfully and the splitting ends successfully, you can
resume business tasks (i.e., you can start business applications) by using secondary data volumes
in the secondary site. Also, if the primary storage system, the secondary storage system, and
remote copy connections are free from failure and fully operational, the restoring of the pair will
finish successfully, and then copying of data from the secondary site to the primary site will start.
For detailed information about how to use Business Continuity Manager and about pair status in Business
Continuity Manager, please refer to Business Continuity Manager User’s Guide.
For detailed information about status of data volumes, refer to “
Transferring Operations Back to the Primary Site
Once the disaster recovery procedure is finished and your business applications are running at the
secondary site, the next activity is to restore the primary site and make arrangements for copying data
from the secondary site back to the primary site. The following procedure explains how to use Business
Continuity Manager to copy data from the secondary site to the primary site:
1.
Restore the primary storage system and remote copy connections, and make sure that all URz
components are fully operational.
2.
At the primary site, locate primary data volumes whose pair status is Pending duplex or Duplex,
and then locate corresponding secondary data volumes whose pair status is Suspend, which is
equivalent to SWAPPING in Business Continuity Manager terminology. If such volume pairs are
found, issue a request for splitting the pairs to the primary data volumes.
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Disaster Recovery Operations