You should be aware of restrictions if you want to use GAD with nondisruptive migration.
- When creating a GAD pair, you cannot specify a volume being migrated by nondisruptive migration as its S-VOL.
- Before creating a GAD pair, you need to change the cache mode of the destination volume to Write Sync. Use CCI when changing the cache mode.
- I/O operations from the host to the GAD S-VOL cannot be done until Volume Migration is completed. If you want to allow the host to recognize the GAD S-VOL, do this after Volume Migration is completed.
- You cannot swap resynchronize GAD pairs. If you want to swap resynchronize them, delete Volume Migration pairs after Volume Migration ends.
- Before you start Volume Migration, set the same provisioning type for both the target volume of Volume Migration and the GAD S-VOL.
- 3-data-center (3DC) configurations using both GAD and Universal Replicator (UR) cannot be used for destination volumes. To use a 3DC configuration combining GAD and UR, configure the 3DC system after volumes are completely migrated by Volume Migration.