HP P6000 Replication Solutions Manager User Guide (T3680-96089, October 2012)

Remote replication guidelines
Storage arrays
• Source and destination arrays must have remote replication licenses. See Replication licenses
overview.
• The array selected for the destination DR group depends on the remote replication configuration.
For supported configurations, see the HP P6000 Continuous Access Implementation Guide.
• A storage array can have DR group relationships with up to two other storage arrays.
• The maximum number of virtual disks in a DR group and the maximum number of DR groups
per array vary with controller software versions. See Controller software features - remote
replication.
DR groups and failover
• Failover of a DR group pair is permitted only by specifying a destination DR group.
• When failsafe mode is enabled, a DR group pair cannot be suspended. See Failsafe on
unavailable member and Suspend on failover.
• When a DR group pair is suspended, it cannot be failed over or reverted to home.
• A DR group cannot be deleted if a virtual disk in the destination DR group is presented.
• For additional help on usage, see Using DR groups.
Log disks
• Logs disks for the source and destination DR groups should be kept the same size.
• The log size cannot be changed when in enhanced asynchronous write mode. See Write
mode.
Write mode
• The write mode cannot be changed if the source log disk is in use or contains data. Before
changing, a non-empty source log disk must be merged to its destination.
• If a source and destination array are not running the same implementation of write mode
(basic or enhanced), only synchronous write mode can be selected.
Virtual disks
• All virtual disks that contain data for an application must be in the same DR group.
• When in enhanced asynchronous write mode, virtual disks cannot be added to or deleted
from a DR group. This restriction is controller software version dependent. See Controller
software features - remote replication.
• When suspended, virtual disks cannot be removed from the source or destination DR group.
• Virtual disks cannot be directly added to a destination DR group.
• To be added to a source DR group, a virtual disk:
Cannot be a member of another DR group◦
◦ Cannot be a snapshot or a mirrorclone. see virtual disks Types
◦ Cannot have a mirrorclone; this restriction is controller software version dependent, see
Controller software features - remote replication.
◦ Must be in a normal operational state, see resources Operational states
DR group concepts 91