Technical data

Installing Expansion Boards
7-6
Boot Device Assignment Example
In this example, the assumption is that “PCI slots” is the selected boot sequence
preference in the SCU.
PCI Scan Order Example
PCI slot 1 PCI 2 channel SCSI controller with an onboard PCI to PCI
bridge chip to an internal PCI bus where one SCSI controller
is attached.
Drive on SCSI Channel 1 (lowest PCI device number) SCSI
ID 3
Drive on SCSI Channel 2 SCSI ID 1
PCI slot 3 PCI SCSI controller such as a 2940W
Drives at SCSI ID 1, 3
In this example, the scanning begins with PCI slot 1 (PCI bus 0) and the two
channel SCSI controller. The two channel SCSI controller has an internal PCI
bus, which is now seen as PCI bus 1. Channel 1 and Channel 2 of this
controller are detected in that order, as Channel 1 has a lower PCI device
number. Finally the 2940W is detected in PCI slot 3. The first device found
during the scan that is bootable will be the boot device. So, if all the drives in
this example were bootable, the boot device would be the drive attached to
Channel 1 on PCI Bus 1 of the two channel SCSI controller (see figure 7-2).