DSM/Tape Catalog User's Guide

Configuring DSM/TC

DSM/Tape Catalog User’s Guide — 520233-008

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Default File Catalog

When the logical name of the file catalog is not specified in a TAPECATALOG DEFINE,

use this command to set the default file catalog:

>MEDIACOM ALTER MEDIADEFS, FILECAT

Default Volume Catalog

To set the default volume catalog, use the MEDIACOM ALTER MEDIADEFS command

with the VOLCAT option. Use this command to specify the logical name of the volume

catalog when it is not specified in a TAPECATALOG DEFINE.

Default Pool

To set the default pool, use the MEDIACOM ALTER MEDIADEFS command with the

POOL option. Use this command to specify the logical name of the pool to use when it

is not specified in a TAPECATALOG DEFINE.

Default Retention

DSM/TC supports the concept of generations of tape files. When a tape file is first

entered in the file catalog, it is assigned a generation number of 1. Each new

generation of the tape file is incremented by one. To read a tape file, programs ask for

the absolute or relative generation they want to use. Relative generations range from 

-1 (the most recent generation) to -n where n is rela

tive to the valid tape file records in

the file catalog.

A retention value is associated with each tape file. The retention determines h

ow long

a tape file is retained in the file catalog. When the retention period or date has elapsed,

the tape file is referred to as expired. All corresponding records are then deleted.

UNLABELED Permits only unlabeled tape processing. TAPE DEFINEs and

TAPECATALOG DEFINEs are not permitted. This level is equivalent

to the SYSGEN option TAPE_LABEL_PROCESSING DISABLED.

INTEGRATED A third-party tape management system is used in parallel with

DSM/TC. The only

DEFINEs that work are TAPECATALOG DEFINEs

with CATALOG ON. Labeled tape processing is allowed only if the

third-party tape management system is running.

TPTMCOMPATIBLE The third-party tape management system is used, and DSM/TC is not

consulted.

Unlabeled and labeled tape processing is permitted. TAPE

and TAPECATALOG DEFINEs are recognized. Cataloged tapes can

be read but not written when the CATALOG attribute is set to OFF.

TPTM The third-party tape management system is used, and DSM/TC is not

consu

lted. Labeled and unlabeled processing is permitted, but only

TAPE CATALOG DEFINEs are allowed.

option Desc

ription (page 2 of 2)