Operating System Software User Manual

Changing Secondary Volume Groups to Primary
If a primary system or primary volume fails, you can change secondary volume groups to primary
volume groups to aid in disaster recovery. Changing secondary volume groups to primary volume
groups:
• Reverses the direction of data replication (if possible)
• Enables I/O to the volume groups
• Allows you to export the volume groups as read/write as part of the disaster-recovery process
(if you do not change secondary volume groups to primary groups, volumes are exported as
read-only)
Changing One Volume Group
To change a single secondary volume group to a primary group, follow these steps:
1. Stop the primary volume group on the primary system (Resynchronization snapshots remain
on the system.) by issuing either of the following commands:
# # stoprcopygroup <group_name>
where <group_name> represents the name of the volume group
or:
# stoprcopygroup -pat <pattern>
where <pattern> represents the pattern of volume group names to stop (for example,
Group*).
2. Issue the following command:
# setrcopygroup failover <group_name>
where <group_name> represents the name of the secondary volume group (for example,
Group1.r96) to change to a primary group.
Changing All Volume Groups on a System
To change all secondary volume groups on the backup system to primary groups, issue the following
command:
# setrcopygroup failover -t <target_name>
where <target_name> represents the name of the primary (failed) system (System1).
For additional information, see:
• “About the Remote-Copy Commands” (page 261)
• “Recovering from Disaster” (page 162)
Changing Secondary Volume Groups to Primary 117