Drive Operations; Introduction; Data Compression Operation - Seagate STD124000N Product Manual

Drive Operations

Introduction

Data Compression Operation

Product Manual
This chapter describes important operational procedures for the Scorpion 24 drive. It
covers the following topics:
z
Data compression operation
z
Front panel LED operation
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Loading and unloading a cartridge
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Using a blank cartridge
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Using a cartridge that contains data
z
Loading revised firmware through Seagate firmware cartridges
Default operation for the Scorpion 24 drive is to have data compression enabled—
the drive automatically compresses all data written to tape and decompresses all
compressed data read from tape.
The degree of compression varies due to the type of data being processed.
Data with high degrees of redundancy, such as structured database files or graphics
files, can be compressed most efficiently, often at a ratio of 2:1 or more. Data with
little redundancy, such as executable programs, can be compressed the least.
The SCSI Mode Select command can switch the drive into compressed or
uncompressed mode for writing data regardless of the position of the jumper
position. When reading, the drive automatically selects compressed or
uncompressed mode, depending on the data that is read.
On internal models, a jumper on the rear panel can also be used to enable or
disable data compression. See Chapter 3 for more information.
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