Seagate ST12450W/WD manual Terminating the drive, Scsi bus termination

20 ST12450W/WD Installation Guide, Rev. B

Terminating the drive

If you are installing aBarracuda 2, 2HP drive in a system that has other SCSI devices installed, terminate only the end devices on the SCSI chain. A SCSI “device” is any disc drive, scanner, tape-backup unit, or other piece of hardware connected to your system using the SCSI bus.

The top example in Figure 3 shows an internal hard disc at one end of the SCSI bus with the SCSI controller at the other end (both are terminated). The bottom example shows two additional SCSI devices connected exter- nally—this means the SCSI controller is no longer on the end of the SCSI chain and should not be terminated.

Internal SCSI cable

Internal	Internal	Controller
SCSI device	SCSI device

Terminate

Internal SCSI cable

Internal	Internal	Controller
SCSI device	SCSI device

External

SCSI cable

External

SCSI device

External

SCSI device

Terminate

Figure 3. SCSI bus termination