Installing external tape drives Connecting a SCSI Cable

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Connecting a SCSI Cable
The external tape drives provide two 68-pin, shielded connectors on the back panel (see Figure 11
on page 35). You can use either connector to attach the drive to the host computer or to another
SCSI device.
The internal tape drives can be used with two SCSI interfaces:
• Wide SCSI — either Low Voltage Differential (LVD) or Single-ended (16-bit Wide mode).
• Narrow SCSI — either Low Voltage Differential (LVD) or Single-ended (8-bit Wide mode).
The tape drive automatically detects whether the SCSI bus is LVD or single ended. Be sure the SCSI
bus is terminated properly.
NOTE: We strongly recommend that you attach the tape drive to SCSI controllers that
support the SCSI Ultra2 LVD interface only. Attaching the tape drive to a non-LVD SCSI
controller or an 8-bit Narrow SCSO controller will degrade the performance of your tape
drive and backup operations. Performance will also be degraded if you attach non-LVD
SCSI devices on the same bus cable as your LVD connection. Do not connect the tape drive
to a disk RAID controller (disk RAID controllers are not supported). If you install an adapter,
we recommend you purchase a SCSI LVD controller kit that includes the SCSI cable and
terminator.

Connecting to a Wide SCSI Connector

If your computer has a 68-pin wide SCSI connector:
1. Turn off your computer.
2. Connect the SCSI cable from the SCSI host adapter or from another unterminated SCSI device
to either of the two 68-pin SCSI connectors on the back of the external tape drive (see
Figure 11 on page 35).
3. If desired, use the other SCSI connector on the back panel of the external tape drive to attach
another SCSI device.If the external tape drive is the last or only device in the SCSI chain, ter-
minate the SCSI chain (see “Checking SCSI Termination” on page38).

Connecting to a Narrow SCSI Connector

The external tape drives have an Ultra Wide SCSI interface. Obtaining a 50-to-68 pin adapter lets
you connect the 68 pins on the external tape drive to the 50 pins on the computer’s narrow SCSI
bus.
1. Turn off your computer.
2. Connect the adapter to your computer’s 50-pin SCSI connector.
3. Connect the SCSI cable with the adapter to either of the two 68-pin SCSI connectors on the
back of the external tape drive (see Figure 11 on page 35).
4. If desired, use the other SCSI connector on the back panel of the external tape drive to attach
another SCSI device.If the external tape drive is the last or only device in the SCSI chain, ter-
minate the SCSI chain (see “Checking SCSI Termination” on page38).