[Info-vax] Unpleasant Disk Shadowing Surprise

[Kenneth Fairfield]

On Wednesday, October 12, 2011 1:11:42 AM UTC-7, tadamsmar wrote:
[...]
> I looked at SHOW DEVICE DK.  I now see that I did not read it
> correctly earlier, and I have been confused about some things.
> 
> The real sequence of events is that DKA100 went offline and DKA0
> logged an error at almost exactly the same time! Those are my shadow
> set. Hopefully that was a soft error on DKA0 so that my data is not
> compromised, I need to double check that.
> 
> I rebooted just before I left work and DKA100 did not even show up
> after the reboot.
> 
> I am now thinking that I probably have a bad SCSI cable.  I will
> replace that tomorrow, I think I have one in storage.
[...]

I find your error analysis logic, hmmm, "unusual".

The first event was that DKA100 went offline.  The
second was that it didn't show up on reboot.  I'd
call that a bad disk.  

Why (in the world) do you jump to the conclusion that
it's the SCSI cable???  You do understand that the same
cable is used to access DKA0 as DKA100, and if there
were a problem with the cable, you probably wouldn't
be able to boot at all (or at least, without errors) 
off DKA0?

Go replace DKA100 and get on with your life. :-)

   -Ken