Installing Multiple Adapters - Adaptec AHA-3980 User Manual

Installing Multiple Adapters

You can install multiple AHA-398x RAID adapters in the same com-
puter. You can also install an AHA-398x in computers that have
other PCI-, ISA-, or EISA-based host adapters. However, keep the
following considerations in mind:
All drives in an array must be connected to the same host
adapter. A single array cannot include drives from two or more
host adapters.
If you are booting from a SCSI disk drive or array, it must be
connected to the adapter that the computer scans first. Usually,
you need to determine by experimentation which PCI slot the
computer scans first and then make sure the adapter with the
boot device is installed in that slot. Some computers boot from
the device with the lowest PCI device number; others boot from
the device with the highest number. If the system does not boot
from the host adapter you want, move that host adapter to a dif-
ferent PCI slot and try again. Alternatively, you can disable the
BIOS on host adapters that are scanned before the desired boot
host adapter.
In systems with EISA- and ISA-based host adapters, the boot
host adapter must have the lowest BIOS base address. The system
BIOS automatically controls the AHA-398x base address (the user
has no control over the assigned address).
AHA-3980/3980W/3985/3985W User's Guide
Stock Number: 510810-00, Rev. D
Print Spec Number: 493479-00
Current Date: 3/1/99
Installing the AHA-398x and the SCSI Drives
Page: 5-17
ECN Date: 3/19/96
5-17