Adaptec aic7892 Ultra160 SCSI adapter ERROR

[Mark Terribile]

Aurimas Mikalauskas <updates at interdata.lt> writes

>> May 20 10:39:59 banners /kernel: (da0:ahc0:0:0:0): SCB 0x35 - timed out
>> May 20 10:40:04 banners /kernel: >>>>>>>>>>>>>>>>>> Dump Card State Begins
<<<<<<<<<<<<<<<<<
     :
     :

and "Justin T. Gibbs" <gibbs at scsiguy.com> replies:

> This means that your drive decided not to return a command back to the
> controller.  The controller driver was able to clear up the error by
> resetting the device (BDR = Bus Device Reset).
> 
> The failure could indicate a drive firmware bug or that the drive is
> failing.

I have seen similar messages that were traced to SCSI cabling problems.  At the
higher SCSI speeds, the electrical signal just barely has time to settle before
a new signal is introduced (this is _GREATLY_ simplifying the problem; the
science to study is Transmission Line Theory) and the only reason it works is
that the `terminators' absorb energy and keep it from reflecting back into
the line and the cabling rules (on where connectors may be placed) prevent
reflections from occurring where they can cause problems.  The whole thing is
sensitive to poor connections, connections placed too close together, sharp
bends in the cable, cables laced together face-to-face, etc.  And the
problems can be intermittent, or only show up under extreme load.

If you haven't, make sure that the connectors are properly seated, the
correct termination is installed/set, etc., and that the cable is not
folded on itself or clamped face-to-face with another flat cable.
And, of course, make sure that all the device IDs are set correctly.

   Mark Terribile



	
		
__________________________________
Do you Yahoo!?
Yahoo! Domains – Claim yours for only $14.70/year
http://smallbusiness.promotions.yahoo.com/offer