DOCUMENT ID:  0910-02

SYNOPSIS:     DPT PM2x22B/9x caching raid controller problem using RAID5

OS RELEASE:   2.1

PRODUCT:      Solaris x86

KEYWORDS:     DPT PM2x22B/9x cache raid controller RAID5


DESCRIPTION:

DPT 2022 or 2122 is a supported controller under X86, but you should
avoid using RAID5 configuration.  This problem is corrected on the next
release 2.4.  Bug id#1164128


SOLUTION:

You need to choose a different configuration other than RAID5 under DPT
controller configuration. 

If you configure your hard drives under DPT 2x22 controller as RAID5
configuration, Solaris install will fail with the following error
message right after "Begin Installation" stage:

"Failed to create file system: /dev/rdsk/c0t0d0s0"

And the installation will abort.

You will also see a log entry in the /tmp/install_log file something
similar to:

"With 16065 sectors per cylinder, minimum cylinders per group is 16 and
the fragment size to be changed from 0 to 4096"

The problem was that mkfs expects cylinders per group to be 10, not 16. 
This problem has been fixed on 2.4. 


DATE APPROVED: 10/23/95