[rescue] Needed: SM61/SM81

[Skeezics Boondoggle]

On Mon, 15 Mar 2004, Lionel Peterson wrote:

> > From: Patrick Finnegan
> 
> > Does anyone have spare SM61's or SM81's that they'd
> > be willing to part with?  I think that I could use
> > up to 8 more CPUs to max out the boards I've got.
> 
> www.ebay.com, search for seller "ssinc1500" (or "sm81") - $20/pair
> 
> No connection, happy customer (many times over, over the years)

I've tracked "ssinc1500" auctions for a while too.  When looking at SM81s
for a 2000E, however, you really want that 2nd MB of cache - so check your
part numbers carefully:

	SM81 (1MB)		SM81-2 (2MB)
	501-2953		501-3022
	501-3033		501-3098
	501-4810		501-4780
				501-5056

If you mix'n'match the 1MB and 2MB modules, the 2000E will only use the
first MB on all CPUs.  Also, putting a 2MB module in anything but a 2000
or 2000E is a waste - nothing else will use the 2nd MB.  And there can be
some funkiness with mixing revs; you'll want to read the notes in the FE
Handbook very carefully in case you run into compatibility issues.  (With
dual SM71s or SM81s the SS20's tend to prefer the newest rev chip in Mbus
slot 0; I can't recall if the SC2Ks are as finicky, but I generally put
the newest module in board 0, slot 0...)

When people auction SM81s and don't list part numbers, I usually send an
email to the seller to request that they update the auction to explicitly
state that the SM81-2 modules are _wasted_ in anything other than a
2000/E, because they were (and are) pretty rare at one time, and it makes
me cringe that folks are running SS10s or 20s with 2MB modules that should
rightfully be in a 2K...

The SC2000s are great machines.  I'm about to pick up a 4th machine, as
soon as I finish decommissioning it.  This is a box that has been online
continuously since late 1993 when it was purchased new, with six Sparc
Classics, for $249K (at .edu discounts).  Since then it's run virtually
everything (services and interactive logins) for the computer science
department at a local grad school.  From '97 to '00 I managed the machine,
upgrading it from a 6x40Mhz, 512MB config to a 50Mhz backplane and pushing
it to 12x85Mhz, 2GB + 8MB Prestoserve, 18 disks on 11 SCSI chains, and 7
Ethernets.  It's still running today (unpatched since y2k and just
screaming "own me!  own me!" :-/) but up solid for stretches of 400+ days
at a time, between A/C or power failures... great hardware.  Built like a
freakin' tank.

And as Dave M pointed out, *damn* that's a ton of SCSI adapters. :-)  
Clearly that box had more connected to it than the two 6-bay trays shown
in the pictures... care to post the 'prtdiag -v' output? :-)

-- Chris