DSM/Tape Catalog Operator Interface (MEDIACOM) Manual

MEDIACOM Commands
DSM/Tape Catalog Operator Interface (MEDIACOM) Manual—429828-010
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ADD POOL Command (Super Group Only)
Considerations

Density conflict when writing a tape
The density of all tapes in a pool must agree with the pool’s density if the pool was
assigned a density other than ANY. The tape’s density is used when writing data to
it.
If you specify a density in a TAPECATALOG DEFINE that is different from the
density of the tape, a conflict arises over which density to use. No data is written to
the tape, and an error is sent to the tape console and application. Processing stops
until the problem is resolved, usually by you changing the TAPECATALOG DEFINE
to remove or revise its DENSITY attribute before rerunning the application.

Grouping tapes in a pool by common attributes
Except in special cases, restrict a pool to one type of label, density, and tape type.
For example, all tapes in a pool could be 2400-foot open reels with ANSI labels
and a density of 1600 bpi.

Cartridge tapes for a tape library
Cartridge tapes stored in a tape library should be cataloged in the same pool with a
type of cart3480. Always keep such tapes in the tape library unless they are
removed for long-term storage or because they are defective.

Backup tape labels
Little difference exists between an ANSI label and a backup label. BACKUP and
BACKCOPY accept either type of labeled scratch tape as an output tape. (During
the BACKUP or BACKCOPY run, an ANSI output tape is modified in its label so it
is recognized after the run as a backup labeled tape.)
If you used both label types with BACKUP and BACKCOPY before DSM/TC was
installed, you can continue to do so with DSM/TC by cataloging ANSI or backup
labeled scratch tapes in a pool with a label type of ANY.
To keep ANSI labeled tapes completely separate from backup labeled tapes,
catalog the ANSI tapes in a pool with a label type of ANSI and the backup tapes in
a pool with a label type of BACKUP.

Excluding a pool from the system search space
A tape belonging to a pool excluded from the system search space is not
recognized when mounted on a tape drive. When a tape from an excluded pool is
needed, the tape drive name must be given in the TAPECATALOG DEFINE using
the DEVICE attribute. For information on TAPECATALOG DEFINEs and tape
processing concepts, see the DSM/Tape Catalog User’s Guide.

Changing search space attribute of an existing pool
To change the pool attributes set by the AUTOSCRATCH, DENSITY, LABELS, and
TYPE options for an existing pool, use the ALTER POOL command. However, you