SCSI reset ?

[Mike Bilow]

Guenther Fischer wrote in a message to Mike Bilow:

 GF> I will setup a linux box for squid. Its a dual processor PPro 
 GF> with a UltraWide SCSI Adapter AHA 294x and 3 9G Micropolis.
 GF> After some hours of haevy load the server hangs with 
 GF> SCSI-problems: 

 GF> I/O error (timeout) -> SCSI reset -> ...

 GF> any ideas?

You're not going to like this, but we are currently fighting the same problem
with, of all things, NetWare 4.11.  The early suspicion is that there is
something in the Intel 440FX chipset used on dual P6 boards that is responsible
for this, possibly relating to cache coherency.  We have swapped everything,
including cables, connectors, RAM, VRMs, brands of hard drives, and so forth.
We have slowed the SCSI bus to minimum speed.  Worst of all, we can replicate
the problem with a second similar machine, proving that the problem is systemic
rather than a simple defect!

It would be extremely helpful if you could give me more specific details of
your situation, especially the type of motherboard.  I doubt that you have
uncovered a Unix-specific issue, but I would assume that Unix would be as
affected as NetWare by a hardware problem of this type.  I plan to test this,
but I need to fine time to install Linux/FreeBSD on one of these machines.
 
-- Mike