Practice volumes
You can use a practice volume to practice what you would do in the event of a disaster, without interrupting current data replication. Practice volumes are available in Metro Mirror, Global Mirror, Metro Global Mirror, and Metro Mirror - Global Mirror sessions.
To use the practice volumes, the session must be in the prepared state. Issuing the Flash command against the session while in the Prepared state creates a usable practice copy of the data on the target site.
Note: You can test disaster-recovery actions without using practice
volumes. However, without practice volumes, you cannot continue to
copy data changes between volumes while testing disaster-recovery
actions.
Note: After fail over to Site 2 and then fail back to Site 1 have both been
performed, a subsequent Start of H1-H2 will require a full push of data because there is no longer a
bitmap between H1 and H2 because of the force fail over from H2 to H1 done during Recover H1,
therefore the bitmap at I2 may be inconsistent with H1 and cannot be used for the subsequent
synchronization.