Seagate BARRACUDA 36 ST136475LW/LC - Manual (Page 23)

Barracuda 36 Installation Guide, Rev. B 21
the case, change the ID so that each device on the SCSI chain
has its own unique ID. Also check your system or controller
user’s manual to ensure that you have not violated its SCSI ID
numbering recommendations.
Drive termination
If you are installing a Barracuda 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 sys-
tem using the SCSI bus.
The top example in Figure 2 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 externally—this means the SCSI con-
troller is no longer on the end of the SCSI chain and should not
be terminated.
Note. Some controllers prefer to remain terminated even if they
are in the middle of the chain. Also, some controllers treat
the internal and external chains as separate logical
buses. This means you may need to terminate both the
first and last devices on both logical buses to achieve
proper termination. If necessary, refer to your system or
controller documentation to see how this is handled in
your particular system.