A pubset must be assigned to storage level S0 if files of this pubset are to be capable of migration or if pubset-specific default system archives are to be defined that differ from the globally defined default system archives.
If version backups of the files from a pubset are planned to be done, the pubset should be defined as S0. Note that only pubset-specific default system version backup archives can be defined. There is no globally defined archives for version backups.
A pubset of storage level S0 can be assigned an S1 pubset as a background level to which files can be backed up or migrated. A pubset is defined as a global pubset with:
//MODIFY-HSMS-PARAMETERS DEFAULT-HSMS-STORAGE=*PAR - // (S1-PUBSET-ID=<S1-pubset-id>)
This global pubset is used as a background level by all S0 pubsets unless a different S1 pubset is defined by means of:
//MODIFY-PUBSET-PARAMETERS PUBSET-ID=<S0-pubset-id>, - // STORAGE-LEVEL=*S0(S1-PUBSET-ID=<S1-pubset-id>)
Systems under HSMS management can get by without definition of an S1 pubset: all basic functions can use storage level S2 or private disks instead.