[comp.sys.dec] SI 8-mm on HSC VAX Cluster - dual drive ok?

rossperr@sud509.ed.ray.com (Fred Ross-Perry) (12/18/90)

Hi,

We are considering the purchase of 8-mm equipment for our VAX cluster
from System industries.  We're already worried about throughput, and
worry further about the performance of two drives running simultaneously
on the same SI controller.

Has anyone direct experience with both single- and dual-drive configurations?
what are the limitations you have found?  Should I stop worrying?

Thanks,


-- 
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 Fred Ross-Perry         Raytheon Company
 fredrp@mar.ed.ray.com   Equipment Division
 (508) 440-4481          528 Boston Post Road
                         Sudbury, MA 01776
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cooling@cssmtf.ccs.csus.edu (Mike Cooling) (12/20/90)

Before buying HSC equipment from SI, check out the front page article in
the December 17 issue of Digital Review. Basically due to the court battle
between DEC and SI over HSC/SDI&STI patents, SI has settled out of court and
agreed to "...the gradual elimination of its current HSC-compatable
subsystems, known as the C Series...".

I think purchasing SI HSC disk or tape equipment at this time would be risky 
at best!

herber@bgsuvax.UUCP (Steve Herber) (12/20/90)

From article <1990Dec19.213412.24576@csus.edu>, by cooling@cssmtf.ccs.csus.edu (Mike Cooling):
> Before buying HSC equipment from SI, check out the front page article in
> the December 17 issue of Digital Review. Basically due to the court battle
> between DEC and SI over HSC/SDI&STI patents, SI has settled out of court and
> agreed to "...the gradual elimination of its current HSC-compatable
> subsystems, known as the C Series...".
> 
> I think purchasing SI HSC disk or tape equipment at this time would be risky 
> at best!

I just talked to my SI salesman and I still am not clear what is going on.
I was assured that the level of support for my existing C series drives
wouldn't drop but when I asked about future sales of existing C series
drives, he said that he didn't know and that thing would change over
the next couple of years.

I found a conflict in the DR article when they said that SI would stop
making C series drives for the HSC but it was OK to market RA compatible
drives to run off the VAXBI.  Whats the difference?  I have some SI drives
I run off a VAXBI/KDB50 now and I view then as RA compatible.

Coincidentally, I just got an offer from my SI guy to swap out old disks
for new and a VERY GOOD price.  Is this the start of the fire sale?

Steve Herber			Internet	herber@andy.bgsu.edu
Systems Programming Manager	BITNET		HERBER@BGSUOPIE
Bowling Green State Univ.	UUCP		...!osu-cis!bgsuvax!herber

cooling@cssmtf.ccs.csus.edu (Mike Cooling) (12/21/90)

It's my understanding that in order to support HSC devices, SI reverse
engineered the SDI and STI boards and came up with their own board that will
plug into an HSC and support their disks and tapes. That is why DEC took them 
to court. Other vendors have made protocol converters that plug into DEC's SDI
or STI boards in the HSC, so there is no patent infringement.

If you buy an SI disk that plugs into a BI bus controller, then that disk
can be available cluster wide and no HSC patent infringements will exist.
However that disk is available to the cluster, only if the node it is
plugged into is up and running (ie. no failover or volume shadowing).
It all depends on your needs and goals.

Hope this helps.

-- 
____________________________________________________________________________
Mike Cooling                                    Internet: cooling@csus.edu
Manager, Operating Systems & Network Support
California State University, Sacramento