Corruption with SCSI RAID drives and DAT tape

Corruption with SCSI RAID drives and DAT tape

Post by Nigel Port » Thu, 19 Jul 2001 21:07:35


I have a brand new HP NetServer LC2000 with 2 SCSI-3 18Gb drives on
the first SCSI channel, managed by an HP NetRaid 1M RAID controller
(using the AMI MegaRaid chipset within) and setup as a 36Gb RAID-0
array, and a HP SureStore 24i DAT drive on the second SCSI channel.
The NetServer uses the Symbios 53c896 SCSI adapter to control both
channels at the lowest level. I am running SuSE 7.1 with Kernel 2.4.x.

My problem is this...if I compile the 'megaraid' driver into the
kernel (or have it installed as a module and loaded in the initial
ramdisk image) then I can see the hard disks fine and everything works
fine.....except that I can't see the tape drive (dmesg | grep st0
returns nothing) which I would expect as I haven't loaded any SCSI
driver to control the DAT. If I then go on the load the 'sym53c8xx'
module into the kernel I can see the tape drive and everything appears
to be fine for a short time before I start seeing serious corruption
with the hard disk (doesn't matter whether it's ReiserFS or ext2 -
same deal). After about an hour the drives are so corrupted that the
system crashes fatally.

I assume this is because there is now some ambiguity as to how hard
disk access is taking place; either direct to the disk (via the
sym53c8xx driver) or through the RAID controller (using the megaraid
drivers)?  I can't remove the megaraid module or the kernel doesn't
find the hard disks and can't boot.  What can I do about this? Can I
instruct the sym53c8xx module to only control the second SCSI channel.
If not it seems I have no way of getting my SCSI tape drives to work
with linux - not good!

Does anyone have any experience of this? Any ideas....?