DSM/Tape Catalog User's Guide

DSM/Tape Catalog User’s Guide — 520233-008
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1 Introduction to DSM/TC
Distributed Systems Management/Tape Catalog (DSM/TC) is a software system that
manages tape files and labeled magnetic tapes (open reel and cartridge) in a NonStop
Kernel environment. Using this system:

A tape file can be accessed by name only. You need not know the name of the
tape containing the tape file.

Tape files are protected from being accidentally overwritten.

Multiple tape file generations and versions within a generation can be managed
more effectively.

Disk files copied by the BACKUP utility are easy to track for recovery purposes.

Scratch tapes can be assigned to user groups or applications for their use only.

Tapes can be managed and shared between nodes.

Control of tapes can be centralized on one node.

Full database protection is provided by TMF.

NonStop SQL/MP queries can be made from views of the DSM/TC database.
Magnetic Tape and Tape File Management
DSM/TC manages magnetic tapes and tape files by storing information about them in
NonStop SQL/MP databases. The majority of information is entered and maintained
automatically throughout the life of a tape file and tape.
Using DEFINE Requests
If you are running an application that reads files from tapes or writes files to tapes, you
are familiar with requesting tapes with a CLASS TAPE DEFINE request. If DSM/TC is
to manage tape files and tapes, use a CLASS TAPECATALOG DEFINE request
instead of a CLASS TAPE DEFINE request.
A TAPECATALOG DEFINE is a set of a TAPE DEFINE. Both specify the
characteristics of the input tape file or output scratch t
ape you need. It also triggers:

The cataloging of a new tape file so DSM/TC can manage the file for future
requests
Topic Page
Magnetic Tape and Tape File Management 1-1
Main Components of DSM/TC 1-2
DSM/TC System Terms 1-16
Role-based flexibility in handling MEDIACOM
commands
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