5190/5194 Modular Tape Subsystem Manual

Operating the Cartridge Tape Drive and ACL
5190/5194 Modular Tape Subsystem Manual—426878-002
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Specifying a Compression Modifier in the
PERIPHERALS Paragraph (NonStop Himalaya
Specifying a Compression Modifier in the PERIPHERALS
Paragraph (NonStop Himalaya K-Series Servers)
When you use the PERIPHERALS paragraph of the CONFTEXT file to control
compression (shown in the following example), the compression mode can be changed
by:
•
Reconfiguring and reloading the system
•
Using MEDIACOM to set a systemwide default setting
•
Using the SETMODE 162 procedure call for a specific job
If you want to use a consistent systemwide compression default setting for the 5190
tape drive but you do not use MEDIACOM, you can specify a compression modifier for
that drive in the PERIPHERALS paragraph. The modifiers that control compression
are COMPRESSION and NOCOMPRESSION. For example, to set compression
mode on for the tape drive $BACKUP:
!Device Controller / Macro Modifiers
!Name Unit Number
!
$BACKUP TAPEA.5 5190 COMPRESSION;
It is not necessary to specify a compression modifier in the PERIPHERALS paragraph
if you set a systemwide default setting using the MEDIACOM ALTER MEDIADEFS
command. The MEDIACOM default setting overrides this modifier.
For more information on tape-specific CONFTEXT file entries, see Configuring the
Modular Tape Subsystem by Modifying the CONFTEXT File on page 2-13.
CLASS
TAPECATALOG
DEFINE
command
You can use the CLASS TAPECATALOG DEFINE to specify the
compression default setting for one job. (This setting overrides
the current systemwide default setting.)
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SETMODE 162
procedure call
You can use the Guardian SETMODE 162 procedure call to
specify the compression mode for one write command. (This
setting overrides the current systemwide default setting.)
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SCF (NonStop Himalaya S-series only) You set compression mode
on or off using the SCF ADD and ALTER TAPE command.
However, the MEDIACOM systemwide default setting overrides
this setting.
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Table 4-10. Methods for Controlling Compression on a 5190 Tape
Drive (page 2 of 2)
Method Description Page