DSM/Tape Catalog Operator Interface (MEDIACOM) Manual

MEDIACOM Commands
DSM/Tape Catalog Operator Interface (MEDIACOM) Manual—429828-010
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ALTER MEDIADEFS Command (Super Group or
SECURITY-MEDIA-ADMIN Only)
ALTER MEDIADEFS Command (Super Group
or SECURITY-MEDIA-ADMIN Only)
Use ALTER MEDIADEFS primarily to configure various aspects of the DSM/TC system
after installing DSM/TC. It can set:

The name of the default file catalog for the DSM/TC system

The name of the default volume catalog for the DSM/TC system

The name of the default pool for the DSM/TC system

Whether to try more than one time to automatically select a scratch tape in a tape
library

Whether to use compression when writing data to a tape on a tape library drive

The default length of time valid and invalid file entries are kept in the DSM/TC
system
The DSM/TC system default values are used when the AUTOMATED,
COMPRESSION, FILECAT, POOL, RETENTION, or VOLCAT options of a
TAPECATALOG DEFINE are not used.
The system default names for the file catalog, volume catalog, and pool are also used
as session default names when those names are not explicitly set with the FILECAT,
POOL, and VOLCAT commands.
ALTER MEDIADEFS creates the system search list or lists, an important part of a
DSM/TC system. When DSM/TC resides on one node, the system search list contains
only that node’s name. When the DSM/TC system is shared between two or more
nodes, a system search list on each node names the other nodes.
Support Levels
ALTER MEDIADEFS also defines a node’s level of tape support. When a DEFINE is
opened, the support level determines which database is consulted (DSM/TC, a third
party, neither, or both). If a third-party tape management system is used in parallel with
DSM/TC, the support level must be INTEGRATED. If a third-party tape management
system is used alone, the support level must be TPTM or TPTMCOMPATIBLE.
For more information on using ALTER MEDIADEFS to set the tape support level, see
the DSM/Tape Catalog User’s Guide.
Note. If configured, this command can only be executed by SECURITY-MEDIA-ADMIN group
users. If not, only Super group users can execute this command. For information on
SECURITY-MEDIA-ADMIN group, see the DSM/Tape Catalog User's Guide.
Note. The ALTER MEDIADEFS settings used by TAPECATALOG DEFINEs take effect
immediately, but settings used in a MEDIACOM session take effect following the session that
the command was executed.