Step 3: Attach Scsi Cable - HP VS160 - StorageWorks DLT Tape Drive Troubleshooting Manual

Step 3: Attach SCSI cable

A wide VHDCI-to-HD SCSI cable is provided to connect your HP StorageWorks VS160 tape
drive to a VHDCI SCSI port on an LVD SCSI bus. If your server has an HD SCSI port, you must
either purchase and install a VHDCI-to-HD adapter or use an HD-to-HD cable instead of the
supplied cable. Refer to our web site for recommended products:
connect .
Caution To avoid damaging the server or tape drive, ensure that both are powered off while you
attach the SCSI cable.
1 Make sure you are connecting to a recommended SCSI bus type. See "Step 1: Check the SCSI
connection" on page 11. For optimum performance, we recommend that your
HP StorageWorks VS160 tape drive is installed on a dedicated SCSI bus. If it is not, do not
connect it to the same bus as your disk drive. Do not connect the tape drive to the same bus
as a RAID controller, unless you are connecting to a ProLiant server with a Smart Array 6i RAID
controller.
Note: The recommended connections support a maximum bus length of 12 meters. However,
if you daisy chain the tape drive with an Ultra device, cable length is restricted to 3 meters.
Use a 1.8 meter cable to attach the initial unit and a 0.9 meter cable to daisy chain the
additional tape drive. Do not connect more than two tape drives per SCSI controller.
Perform a normal system shutdown and turn off the server and any connected peripherals.
2
3 Attach the VHDCI connection on the SCSI cable to the server's external SCSI connector and
secure it by tightening the screws.
4 Attach the HD connection on the SCSI cable to one of the SCSI connectors on the rear panel
of the tape drive and secure it by tightening the screws. (See Figure 5.)
5 Connect the multimode terminator to the tape drive's other SCSI connector and tighten the
screws to secure it. The multimode terminator detects whether the host bus adapter is SE or LVD
and automatically provides the appropriate termination.
Why does the tape drive need a terminator?
Terminators are essential, as they provide the correct voltages on the SCSI bus and prevent
unwanted signal reflections from interfering with data transfers. The rule is:
There must be termination at both physical ends of the bus and only at the ends.
Normally the HBA forms one end of the SCSI bus and provides termination. You, therefore,
need to ensure that the other end of the bus is terminated. If the tape drive is at the end of
the SCSI bus, the terminator must be attached to the tape drive.
If you want to attach additional devices to the SCSI bus after the tape drive, you will need
to remove the SCSI terminator and attach the next device to this SCSI connector. Make sure
that you attach the terminator to the last device in the chain.
www.hp.com/go/
15