Quantum DLTtape DLT 2000, Руководство пользователя

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media, however, a defect on the tape – say a scratch – could be as
long as an inch without causing an unrecoverable error. That’s
because the parallel channel architecture used in DLTtape drives
enables the system to automatically rewrite bad blocks to parallel
channels.
Maintaining Compatibility
Figure 2-3 shows the linear-serpentine recording pattern used in
DLTtape drives through the DLT 4000 model. The vertically-orient-
ed pattern requires guard bands between tracks to prevent cross-
track interference. In the DLT 7000 and DLT 8000 drives (see Figure
2-4), data density was increased by angling the data pattern on
WHAT IS THE DLTtape SYSTEM? 2.4
3mils
Track 0
Track 1
Track 2
Bottom edge of tape
Tape Direction
Figure 2-3 DLT 4000 Drive
writes data on two channels simultaneously
in linear tracks that run the length of the tape. The system has a capacity of
20GB native and 40GB compressed.
1.75mils
Bottom Edge of Tape
Track 3
Track 2
Track 1
Track 0
Track 4
Tape Direction
Figure 2-4 DLT 7000 and DLT 8000 Drives’ Symmetric Phase
Recording
™
writes data in an angled pattern, allowing higher data
density, with per cartridge capacity of 40GB native and 80GB compressed.