9710 (StorageTek) Addendum for NonStop Servers

Addendum to the StorageTek™ 9710 for the Tandem Environment
The 5155/5159 Digital Linear Tape CRE and NonStop Kernel
9-47
9.5.3 Methods for Controlling Compression
There are several ways to control compression for the 5155, 5159,
5150 or 5151 tape drive. Some methods are described in the
following table:
Method Description
The
PERIPHERALS
paragraph modifier
This is a convenient way of permanently
setting the compression mode for the tape
drive if MEDIACOM is not being used. (The
MEDIACOM system-wide default overrides
the PERIPHERALS paragraph setting.)
COUP If there is no system-wide default, the COUP
compression device attribute can be used to
enable or disable compression for the tape
drive being configured. (The MEDIACOM
system-wide default overrides the COUP
setting.)
MEDIACOM The MEDIACOM ALTER MEDIADEFS
command sets a system-wide default.
The CLASS
TAPECATALOG
DEFINE command
The CLASS TAPECATALOG DEFINE can
be used to specify the compression default for
one job. (It overrides the current system-wide
default.)
The SETMODE
162 procedure call
The SETMODE 162 procedure call can be
used to specify the compression mode for one
write command. (It overrides the current
system-wide default.)
The details of each of these methods are described next.