Archiving Data In Compressed And Noncompressed Mode - HP 2240 Owner's Manual

The tar (tape file archiv-
er) command saves files
to a data cassette, re-
stores files from a data
cassette, or lists files on
a data cassette.
3-14
Device Files — Data Compression
If you wish to use the data compression feature, use the device files
/dev/rmt/3hc and /dev/rmt/3hcn, which are set for SCSI ID 3.
If you use the /dev/rmt/3hc device file, the tape drive compresses the
data and rewinds the data cassette every time the system releases the
drive from its control.
If you use the /dev/rmt/3hcn device file, the drive compresses the
data, but does not rewind the data cassette. The tape stays where it
was after the last operation.
If you use these device files, you do not need to create any device
files.

Archiving Data in Compressed and Noncompressed Mode

This section describes how to transfer data to and from a DDS- for-
mat data cassette (saving and restoring) using the HP-UX tar com-
mand and your tape drive's device file.
NOTICE: Before using your DDS-format tape drive to
back up your file system, make sure you read
the "Media Interchangeability Restrictions"
section later in this chapter.
The tar (tape file archiver) command allows you to save files to a
data cassette, restore files from a data cassette to your system, or list
files on your data cassette.