Interface specifications and requirements for parallel SCSI
The parallel SCSI Autoloaders use the SCSI interface types described in
use a separate SCSI ID for each tape drive, with dual LUNs on the master drive's SCSI ID to control
the tape drive (LUN 0) and Autoloader robotic (LUN 1). HP recommends that each Ultrium tape drive
be put on its own bus when possible.
Table 6 Parallel SCSI interface types
The parallel SCSI Autoloader incorporates a wide SCSI-2 or SCSI-3 Low-Voltage Differential (LVD)
SCSI bus. Make sure your SCSI host adapter or controller supports these standards.
The Tape Autoloader is NOT compatible with a high-voltage differential (HVD) SCSI bus. Do not put
the Autoloader on a narrow (50-pin) parallel SCSI bus because doing so will severely degrade
Parallel SCSI host bus adapters (HBAs)
For optimum performance, place the Autoloader on its own SCSI bus with a host bus adapter that
can transfer data as fast as the Autoloader can read and write. The HBA must also be supported by
your operating system. Refer to the EBS matrix at
For LTO-3 or LTO-4 tape drives, use an Ultra 320 HBA.
For LTO-2 tape drives, use an Ultra 320 or Ultra 160 HBA.
Do not connect an Ultrium tape drive to an SE SCSI bus, as it severely degrades Autoloader
performance. A single-ended SCSI host bus adapter severely degrades Autoloader performance and
limits cable length. Also, if any SE devices are on the SCSI bus, all of the devices on the bus slow
down to SE speed, severely degrading performance.
Multiple LUN support
The Autoloader uses a single SCSI ID and two logical unit numbers (LUN). LUN 0 controls the tape
drive and LUN 1 controls the robotic. The Autoloader requires an HBA that supports multiple LUNs.
If multiple LUN support is not enabled, the host computer cannot scan beyond LUN 0 to discover the
Autoloader. It just sees the tape drive.
Features and overview
Ultra 160 SCSI LVD/SE
Ultra 320 SCSI LVD
6. The Autoloaders
for current HBA