A scratch volume is an optical volume that is not yet associated
with an Object storage group or an Object Backup storage group.
If an optical volume is not pre-formatted and labeled, it must
be labeled with a unique volume serial number before it can be accessed
by OAM. This task can be completed in either of two ways:
- Labeling an unlabeled optical disk on an operator-accessible optical
disk drive in response to a LABEL command which is entered by the
operator
- Labeling an unlabeled optical disk on a library-resident optical
disk drive as a result of being inserted into the input/output station
of an optical library
In either case, the operator is asked to supply the volume serial
number for each side of the optical disk. The volume labels are written
and rows are created in the volume table in the OAM configuration
database. The volumes are marked as scratch volumes or grouped volumes
depending on how the operator replies to the CBR4432D message during
label processing.
Both sides of a scratch volume become either grouped or backup
volumes when a scratch volume is used to satisfy an out-of-space condition
in an Object or an Object Backup storage group.
Note: Because WORM optical volumes that are full or have
very little free space are not as useful as scratch volumes, the operator
is notified by message CBR4451I if the kilobytes that are free are
less than the SCRENTRYTHRESHOLD parameter. The message contains the
number of kilobytes that are free and the percentage of free space
that this represents on the volume. This gives the operator the opportunity
to fail the cartridge entry process by responding through message
CBR4452D, thus causing the cartridge to be ejected from the library.