HP NonStop G-Series - Manual (Page 112)

Tape Library Control Path Configuration Guidelines
DSM/Tape Catalog User’s Guide — 520233-008
7 - 4
Configuring the AUTOMATED Attribute
Automated OFF means that TMF requests for online and audit dumps do not try a
different scratch tape name if the selected scratch tape is not in the tape library. If
AUTOMATED is specified as ON, and if the scratch tape is not in the tape library, a
different scratch tape is requested, up to a maximum of 10 tape volumes.
For tape drives that support software control of compression, Compression OFF
means that, as a default, compression is not attempted when writing to a scratch tape
volume.
Configuring the AUTOMATED Attribute
To set the AUTOMATED attribute to ON:
MC>ALTER MEDIADEFS, AUTOMATED OFF
1 system defaults altered.
The INFO MEDIADEFS command shows the status:
MC>INFO MEDIADEFS
Support Level NOCATALOG

Automated OFF

Compression OFF
Configuring Compression
To set the system default for compression, use the MEDIACOM command ALTER
MEDIADEFS with the COMPRESSION option. (When using this option, the IDRC
attribute means use compression when writing data to a tape. OFF means do not use
compression.) To support compression mode write for labeled tapes, $ZSVR stores the
default system value for compression.
If COMPRESSION IDRC is specified as the default, any tape drive that has
compression capability (supports compression and contains the appropriate hardware)
compresses data when writing. For tape drives that do not have compression capability
or do not support software control of compression, specifying COMPRESSION has no
effect.
Applications can use the COMPRESSION attribute of a TAPECATALOG DEFINE to
override the current system default. However, applications specifying a TAPE DEFINE
must always use the system default because no compression parameter exists for a
TAPE DEFINE.