3 Feb
2013
3 Feb
'13
1:40 p.m.
On Feb 2, 2013, at 5:11 PM, Pete Turnbull wrote:
On 02/02/2013 18:11, Dave McGuire wrote:
Did this while I was at IBM. We typically had demos of 2-3 systems accessing a
number of shared disks.
It's called multi-initiator mode. Though it was supposed to work (as per spec), not
all devices were great at having multiple initiators (hosts) on the same bus.
Slightly different, Adaptec did produce a device called a "Nodem" which was a
SCSI device that connected to ethernet. Was pretty cool in concept. However, I spent a
lot of time working with Adaptec and it has some serious bugs that they could never quite
work out. The biggest was they had a minimum interpacket time in order to receive an
ethernet packet. Unfortunately, the Nodem's interpacket time was longer than the
minimum interpacket time on ethernet. This resulted in some cases of missed packets.
:-(
TTFN - Guy
On 02/01/2013 09:42 PM, Jeff Jonas wrote:
A company called Lingenuity did the same with a product called SCSI
Share, for Acorn computers, around 1989 or 1990. It allowed six
computers to share a SCSI drive, which appeared as two partitions, one
read-only for software and one read-write for shared files. Of course
distances were limited by the SCSI bus, which meant you needed decent
cables and all the devices more or less on the same tabletop. But I
have seen it working on more than one occasion.
Long ago when SCSI was young
and just an 8 bit parallel bus,
Ampro littleboards advocated using the SCSI bus
for peer to peer communications, not just master/slave.
Did anyone else do that?
One used to be able to do it with Suns, in the Good Ol' Days. I've
not done it myself but have seen it done. It was really quite neat.