Re: ARGH, weird SCSI I/O errors on second/third drive on Debian/PPC
On Fri, 27 Dec 2002, Michael D. Crawford wrote:
> Could the original drive still be terminated after you have installed the other
> drives? It is probably worse to have extra termination than to have none at
> all. Make sure you've got it right.
The original drive was NOT installed at the end of the chain. (The
original Apple-branded CD-ROM drive was...) So I don't think termination
would be an issue for this drive, no?
How do I know if I got it right? I wish there was a "scsidiag" program
that would say "Your termination sucks, try this; your SCSI IDs have a
conflict, try this..."
> I think on my 8500 the original configuration had the boot drive in the middle
> of the bus, the CD drive at one end and the host bus adapter at the other end.
> The CD drive was terminated.
> If your CD drive is providing the termination there is probably a jumber that
> you can remove. If your hard drive is terminated on the drive, there is
> probably a resistor pack you can remove - although it is probably harder to be
> certain you're pulling the right thing off.
The thing that confuses me is thus: There are several termination options
for the drive I placed at the end of the SCSI chain (read the Web page I
referred to: http://www.seagate.com/support/disc/scsi/st15150n.html ). I
do not know which ones are correct. "Terminate power from drive"?
"Terminate power to SCSI bus"? I know nothing of these things.
> There is a Mac OS utility called SCSI probe you might find helpful. The
> version of it that Adaptec distributes is a pretty fancy version. I think it
> might tell you if your bus is terminated correctly. I'm not sure but you might
> try it. Check at http://www.adaptec.com/ it should be available as a free
J e s s i c a L e a h B l a n k