Hitachi G1000 - Page 202

Failure locations
Reference codes of SIMs that
might be issued
Can the volume
access to the GAD
volumes?
1
Primary
storage
system
Secondary
storage
system
P-VOL S-VOL
failure does not cause the GAD pair suspended, or the inaccessible GAD volume
even if a failure occurs in a part of hardware, if the following physical paths are
redundant.
¢
Between a server and a storage systems of the primary and secondary sites
¢
Between an external storage system and storage systems of the primary and
secondary sites
¢
Between storage systems of the primary and secondary sites
2. A SIM that corresponds to the failure type is issued. You might not be able to view
SIMs according to the failure type.
3. You can access the S-VOL, if the pair status of the S-VOL is SSWS, even if a failure
occurs.
Steps for recovery from the failure
1. Using the alternate path software, delete the alternate path to the GAD P-
VOL.
2. At the secondary storage system, delete the GAD pair forcibly.
Select Enable for Volume Access in the Delete Pairs window.
3. Confirm that the GAD pair is deleted.
4. Using the alternate path software, resume I/Os from the server to the
GAD S-VOL.
5. Restore the primary storage system from the failure.
6. At the primary storage system, delete the GAD pair forcibly.
Select Disable for Volume Access in the Delete Pairs window.
Depending on the failure type of the primary storage system, after the
primary storage is restored from a failure, the pair status of the P-VOL
might change to SMPL, and the GAD reservation attribute might be set. In
this case, you do not need to delete the GAD pair forcibly.
7. Confirm that the GAD pair is deleted.
8. Restore the external storage system from a failure.
9. From the primary and secondary storage systems, delete the quorum
disk.
Depending on the failure type of the external storage system, after the
external storage system is restored from a failure, a quorum disk can be
deleted. In this case, you do not need to delete the quorum disk.
10. From the primary and secondary storage systems, add a quorum disk.
11. From the secondary storage system, recreate a GAD pair.
12. Using the alternate path software, add a path to the GAD P-VOL, and then
resume I/Os.
6-50
Disaster recovery of global-active device
Hitachi Virtual Storage Platform G1000 Global-Active Device User Guide