There are two options for the management of private volumes:
- The simpler option allows sharing of private volumes among all
systems in all SMS complexes. This requires that each SCDS have the
same set of tape storage group definitions. All storage groups with
the same name must reside in the same set of libraries, though the
storage group state on each system in the SMS complex can vary. The
cartridge entry installation exit must also be the same on all systems.
- The other option, which proves more difficult, is to restrict
access to private volumes to a single SMS complex. Each SCDS can have
its own set of tape storage groups; an attempt to use a private volume
in a SMS complex where its assigned storage group does not exist causes
the job to fail. When existing private volumes are entered into the
library, the cartridge entry installation exit must recognize the
volumes which belong to its particular SMS complex. If this is not
possible, the volumes may be assigned to the blank storage group at
cartridge entry time, then selectively assigned to the proper storage
group by the storage administrator at some later time.
No matter which private volume management mechanism is selected,
it should be noted that a permanent association between the volume
and a particular SMS complex is not possible. When the volume use
attribute is changed from private to scratch, the volume becomes eligible
for use on any system sharing the ATLDS, or the MTL.