Frank-Christian Kruegel wrote:
> On Sun, 06 Nov 2005 15:53:04 +0000, Dave <nospam@nowhere.com> wrote:
>
>
>>I have a 9 GB (hence reasonably old) disk which refuses to be seen even
>>at the OK prompt with a probe-scsi in a SPARC 20. One might conclude the
>>disk is dead, but it seems to work fine in a Ultra 80. Both machines run
>> Solaris 9, although I patched the SS20 last night, so it is more up to
>>date.
>
>
> The sun4m esp fast scsi controller is 8 bit only. I'm unsure whether the
> upper 8 bits of the wide (16 bit) sca connector are terminated properly or
> have been left open. Some wide hard disks hang unless both lower and upper 8
> bits are properly terminated.
>
> Maybe jumpering the drive to single ended may help. Jumpers for drive id or
> termination have to be removed.

Thanks for that.

I checked and found the disk was already jumped SE. I removed the jumper
(what else to try?) but no luck. I tried a few other jumpers, but no
improvement.

What was odd though is that

a) The disk is seen if it is the *only* disk in the machine.

b) The disk is seen if it the lower slot (SCSI ID=3), but not if its in
the upper one (ID=1). And no, there are not any jumpers installed on
any of the SCSI ID select pins.

Anyway, it is at least semi-resolved. I've put an operating system on it
and it boots OK now. Just needs to be in the lower slot, otherwise it
can't be seen on the bus.

> You may try a SunSwift fas wide scsi controller.

It gets away from the compactness of the SS20 though. I think I'd rather
get a disk that works.

I've often found Compaq disks "funny". Don't know what they do, but
whereas a normal Seagate, IBM or whatever seems to work with no hassle,
those badged Compaq seem to present me more hassles.