Recovery in a 3dc cascade configuration – HP XP P9500 Storage User Manual
Page 106
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“Recovering from primary site failures (when delta resync operation is performed)” (page 109)
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“Recovery with Business Copy Z configuration ” (page 113)
Recovery in a 3DC cascade configuration
If a disaster or failure occurs in the primary site of a 3DC cascade configuration, you transfer
business operations to the intermediate Continuous Access Synchronous Z secondary volume
(S-VOL) site.
After this is done, the primary site should be corrected and brought back online. Then, you have
choices for proceeding: re-create the cascading configuration, or change the Continuous Access
Journal Z/Continuous Access Synchronous Z configuration to multitarget. These procedures are
described in the following subsections.
To transfer business operations to the secondary site
1.
Check consistency of the Continuous Access Synchronous Z R-VOL in the intermediate site.
2.
Use Business Continuity Manager to execute the YKSUSPND REVERSE command on the
Continuous Access Synchronous Z pair.
3.
Use the Continuous Access Synchronous Z R-VOL in the intermediate site to resume your
business tasks.
4.
Use Business Continuity Manager to execute the YKRESYNC REVERSE command onto the
copy groups that make a Continuous Access Synchronous Z pair between the primary site
and the intermediate site. This operation reverses the copy direction.
Transferring business tasks back to the primary site
To transfer business tasks back to the primary site, follow the procedure below. Business Continuity
Manager is used in this procedure:
1.
Stop business tasks at the secondary site.
2.
If the disaster recovery operation (as explained in
“Recovery in a 3DC cascade configuration
) could not change the Continuous Access Journal Z pair status to Duplex and
could not reverse the copy direction, use Business Continuity Manager to execute the
YKRESYNC REVERSE command (a command for re establishing a pair) onto the journals that
make a Continuous Access Journal Z pair between the intermediate site and the secondary
site.
3.
Wait until the status of the Continuous Access Journal Z pair changes to Duplex.
4.
Use Business Continuity Manager to execute the YKSUSPND REVERSE command (a command
for splitting a pair and stopping the copy operation temporarily) onto the journals that make
a Continuous Access Journal Z pair between the intermediate site and the secondary site.
5.
Wait until the status of the Continuous Access Journal Z pair changes to Suspend.
6.
If the Continuous Access Synchronous Z volume is not in Simplex status, use Business Continuity
Manager to execute the YKDELETE command (a command for releasing a pair) onto the
Continuous Access Synchronous Z pair, and then wait until the status changes to Simplex.
7.
If the Continuous Access Synchronous Z volume is in Simplex status, use Business Continuity
Manager to execute the YKMAKE REVERSE command (a command for establishing a pair)
onto the Continuous Access Synchronous Z pair that exists between the primary site and the
intermediate site.
8.
Use Business Continuity Manager to execute the YKSUSPND FORWARD command onto the
Continuous Access Synchronous Z pair that exists between the primary site and the intermediate
site.
9.
Use Business Continuity Manager to execute the YKDELETE command onto the Continuous
Access Synchronous Z pair that exists between the primary site and the intermediate site.
106 Disaster recovery operations