In contrast to the other HSMS functions, there are a great many control options for migration, and there is also a greater need for control.
In contrast to backup or archival, which can be used on any pubset, migration is possible only on pubsets that have been placed under HSMS management and assigned to storage level S0. The files of the pubset which reside on an assigned Net-Storage volume (storage type NET-STORAGE) are excluded from migration.
In particular, the HSMS administrator (or system administrator) is responsible for protecting important system files from being migrated (see section “Except file” for more information).
Migration in shared pubset systems
The migration of a file on a shared pubset can also be initiated from the slave. However, the actual processing of requests takes place on the master for performance reasons.