Host Scsi Channel Problems - Adaptec DuraStor 7220SS User Manual

disk drives from two different vendors may differ in capacity by
100 MB. With a backoff of 0%, you would not be able to replace an
array member's slightly larger 18-GB disk drive with a smaller 18-
GB disk drive. If you intend to only use identical disk drives from
the same vendor, then you can use a backoff of 0%.
The default setting is 1% backoff. This default allows you to easily
work with disk drives that have the same nominal capacity, but
different actual capacities. The backoff percentage affects all arrays
created on the controller after you set the percentage.
If the disk drives in an array are not equal in size, the array
capacity in a RAID 5 array is based on the smallest member's
capacity. The backoff percentage is then backed off the capacity
from that amount.
To change the backoff percentage:
1
From the System Menu, select Configuration Menu and press
Enter.
The Configuration Menu appears.
2
Select Backoff Percent and press Enter.
The Backoff Percent prompt appears.
3
Type the backoff percent you want to use and press Enter.
Type the percentage as three digits using the following format:
00.0%. The default is 01.0%.

Host SCSI Channel Problems

Problem: The host SCSI BIOS scan displays "Device name not
available".
The controller is properly connected, but no arrays have been
created. Use Adaptec Disk Array Administrator to create an array
and reboot the host system.
Problem: The host SCSI BIOS scan hangs.
Check that termination is set correctly in the Configuration Menu
and the disk drive storage enclosure. Check that the device ID set
in Adaptec Disk Array Administrator does not conflict with any
Troubleshooting
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