DSM/Tape Catalog Management Programming Manual

DSM/Tape Catalog Management Programming Manual—520481-003
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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.
The DSM/TC subsystem manages magnetic tapes and tape files by storing information
about them in HP NonStop SQL/MP databases. The majority of information is entered
and maintained automatically throughout the life of a tape file and tape.
With DSM/TC, the problems associated with hand management of tapes and tape files
disappear. All the information you need about your tapes and tape files is automatically
captured and stored in a catalog system to which you have easy access. Because
DSM/TC works with the NonStop Kernel tape server process, $ZSVR, all tapes are
verified as being correct before the application is given access to them. It is virtually
impossible for an application to write over an unexpired tape file.
The Advantages of Using DSM/TC
The advantages of using DSM/TC to manage your tape environment are:
•
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 HP BACKUP utility are easy to track for eventual recovery.
•
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 the HP NonStop Transaction Management
Facility (TMF).
•
NonStop SQL/MP queries can be made from views of the DSM/TC database.