Seagate BARRACUDA 9 ST19171WD - Manual (Page 24)

22 Barracuda 9 Installation Guide, Rev. B
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.
For information about how to terminate your drive, refer to the
appropriate drive-specific section.
Figure 2. SCSI bus termination
Internal
SCSI device
Internal
SCSI device
Controller
External
SCSI device
External
SCSI device
External
SCSI
cable
Internal SCSI cable
Terminate
Internal
SCSI device
Internal
SCSI device
Controller
Internal SCSI cable
Terminate