If you use the HSM feature, Backup requires a specific pool to receive the premigrated and migrated save sets. If you do not associate the migration data with a customized migration pool, Backup automatically uses the preconfigured Migration pool. You must mount an appropriately labeled volume on a storage device for the premigration and migration processes to proceed smoothly. See Failed Cross Reference Format for more information on the Backup HSM feature.
Archive and migration data are in a different format than regular Backup save set data. Therefore, they must be written to different volumes. Because of these differences, the client file indexes and bootstrap save set created during an archive, premigration, or migration operation are also not written to the same volume as the archived or migrated save sets. By default, they are written to a volume from the Default pool. If you need to direct the client file indexes and bootstrap to a volume pool other than Default, see "Example: Directing Client Indexes and Bootstrap to a Separate Pool " for information.