HP StorageWorks SDLT 320, Справочное руководство

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Operating System Device Drivers
11 SDLT Tape Drives Reference Guide
Open VMS
The OpenVMS operating system uses native SCSI recognition for locally attached
SCSI drives, which allows the operating system to recognize the SDLT drive.
Recognition of the SDLT drive allows non-default settings, such as the density
setting, to be used.
SCSI recognition for the SDLT drive is not supported for SCSI drives on any
client node in an OpenVMS cluster that is running version 7.2-1 or earlier. If the
SDLT drive is served to such a client that client system defaults to a generic SCSI
device and the default settings are used.
The SDLT drive provides compression (called compaction in OpenVMS
terminology) so that the storage capability for tapes can be effectively doubled
when the SDLT drive has been instructed to turn on compaction. This is known as
hardware compaction and should be used instead of the software compaction that
is sometimes provided by software products. The SDLT drive is instructed by the
user to turn on hardware compaction through use of the OpenVMS
INITIALIZE
and
MOUNT
commands. (See these two commands using Open VMS help from
the $ prompt).
The format for the
INITIALIZE
command is:
INITIALIZE
/MEDIA_FORMAT
/MEDIA_FORMAT=[NO]COMPACTION
The
INITIALIZE
command controls whether data records are automatically
compacted and blocked together on any device that supports data compaction.
Data compaction and record blocking increase the amount of data that can be
stored on a single tape cartridge.
Note: Once data compaction or non-compaction has been selected for a given
cartridge, that same status applies to the entire cartridge.
The format for the
MOUNT
command is:
MOUNT
/MEDIA_FORMAT
COMPACTION
201412-003.book Page 11 Thursday, October 3, 2002 9:05 AM