Device Termination - Dell 2100 User Manual

Device Termination

Before installing SCSI devices, you must configure the
termination on the device(s) and for the built-in SCSI
controller according to the guidelines listed in the follow-
ing text.
SCSI logic requires that termination be enabled for the
two devices at opposite ends of the SCSI chain and dis-
abled for all devices in between. To that end, regardless
of whether you are installing internal or external devices,
use the following guidelines:
•
The built-in SCSI controller has active termina-
tion—no action is required.
•
Termination is set on the SCSI hard-disk drive
installed in the left bay of the internal drive bays
when the drive is installed by Dell. Termination
should be disabled on any other drives installed in
the internal bays. Figure 9-1 shows where the termi-
nation jumper should be located on the Dell-supplied
2-gigabyte (GB) and 4-GB SCSI hard-disk drives for
the PowerEdge 2100 system.
•
If you install an optional SCSI controller card to con-
trol the CD-ROM drive and any other SCSI device in
the external bays, you must enable termination for
the SCSI controller card and the SCSI device at the
end of the interface cable (preferably the CD-ROM
drive). See the documentation that came with your
SCSI controller card for instructions. To enable ter-
mination for the CD-ROM drive, place a jumper on
the pins on the back of the CD-ROM drive as shown
in Figure 9-1.
CAUTION: When you install or remove termination
jumpers, do not move or remove any other jumpers
installed on the drives.
9-112 Dell PowerEdge 2100/180 and 2100/200 Systems User's Guide
CD-ROM drive
termination jumper
4-GB hard-disk drive
2-GB hard-disk drive
(bottom view)
Figure 9-1. SCSI Termination Jumper Locations
termination jumper
termination
jumper