DFSMShsm stores
data in a device-independent format so it can move data to any of
the following devices:
- Tape for the 3480, 3480X, 3490, and 3590-1 Magnetic Tape Subsystems.
- DASD for Models 3380, 3390, and 9345.
DFSMShsm supports
the following volume types:
- Level 0 volumes are volumes containing data
sets that are directly accessible to you and the jobs you run. DFSMShsm-managed volumes are those level 0 volumes
that are managed by the DFSMShsm automatic functions.
Level 0 volumes,
and DFSMShsm-managed volumes, can be any DFSMShsm-supported DASD.
These volumes must be mounted and online when you refer to them with DFSMShsm commands.
- Migration level 1 volumes contain data sets
that DFSMShsm moved
from level 0 volumes and contain the backup versions that were created
from a DFSMShsm BACKDS
or HBACKDS command.
Migration level 1 volumes are DFSMShsm-supported
DASD on which DFSMShsm maintains
your data in DFSMShsm format.
Normally, these volumes are permanently mounted and online.
- Migration level 2 volumes are volumes containing
data sets moved from migration level 1 volumes or level 0 volumes.
Migration
level 2 volumes are DFSMShsm-supported tape, or DASD, on which DFSMShsm maintains
your data in DFSMShsm format.
Normally, these volumes are not mounted or online.
- Daily backup volumes are volumes containing
the most current backup versions of data sets copied from level 0
volumes. These volumes may also contain earlier backup versions of
these data sets.
Daily backup volumes are DFSMShsm-supported tape,
or DASD, on which DFSMShsm maintains
your data in DFSMShsm format.
Normally, these volumes are not mounted or online.
- Spill backup volumes are volumes containing
earlier backup versions of data sets, which were moved from DASD backup
volumes.
Spill backup volumes are DFSMShsm-supported tape, or DASD,
on which DFSMShsm maintains
your data sets in DFSMShsm format.
Normally, these volumes are not mounted or online.
- Dump volumes are DFSMShsm-owned magnetic
tape volumes. When a volume is dumped, DFSMShsm invokes DFSMSdss to
write a copy of the entire allocated space of that volume on a dump
volume.
Dump volumes are DFSMShsm-supported
tape. Image copies of volumes are produced by the full volume dump
function of DFSMSdss,
which is invoked by DFSMShsm.
- Aggregate backup volumes contain copies
of the data sets of a user-defined group of data sets, along with
control information for those data sets. These data sets and their
control information are stored as a group so that they can be recovered
(if necessary) as an entity by an aggregate recovery process.
Aggregate
backup volumes are DFSMShsm-supported tape and are normally not mounted
or online.
- Fast replication target volumes contain
the fast replication backup copies of DFSMShsm-managed volumes. Fast
replication target volumes are contained within SMS copy pool backup
storage groups.