Buy more 4/670 parts?

Nov 26 17:49 UTC 1997

In the past, we've always made sure that we had enough extra bits and pieces
of computers so that if we had a hardware failure, we could swap spare parts
in and get Grex running again quickly.

After we shift to the 4/670, we won't have any spare parts, except a few spare
memory chips.  If the 4/670 fails, we will have to fall back to the 4/260.

This isn't a totally simple fall back.  The 4/260 is a slightly different
architecture than the 4/670.  It runs most of the same binaries, but not all.
So if we have to fall back, we need to make software changes as well as
hardware changes.  We will keep around the current 4/260 disk partitions, but
unless we continue to maintain those, they will rapidly become obsolete.  So
if we have a serious hardware failure, it is likely to take us as long as a
day of downtime to get the 4/260 back up.

Options:

(1) Start shopping for spare 4/670 parts:

      motherboard - this contains scsi controller, sockets for the
        first 128Meg of memory, the ethernet interface, and several serial
        ports.  We have only one of these.  I haven't found any prices.
        I think they may be about $500-$600.  (it's called 501-1686 or
        501-2055).

      cpu board - this is a little piggyback board that contains two CPUs.
        The motherboard can take two of these.  We have one.  We originally
        budgetted money for two and bought two, but one of them turned out
        to have only one working processor on it.  I think Rob never charged
        us for this and still has it.  The money to buy a spare was in the
        4/670 budget.  If we buy one, we not only have a spare, but we can
        experiment with running Grex on 4 processors instead of 2.  (Actually,
        using Rob's half-dead board to run on three processors might work
        better than either - we should probably try to acquire that card).
        (I think the ones we have are SM100's, aka 370-1388 - prices seem to
        range from $150-$450).

      chassis:  The chassis we are running the 4/670 in is a newer model
        than the other three we have.  We don't know if it can be run in
        the older chassis.  My guess is that it can be, especially after we
        change over to the terminal server.  After that the 4/670 will be
        essentially a single-board computer, so the only thing it wants from
        the bus is power.  So I don't think there is a hurry to buy a spare
        chassis.

      memory:  In the old Grex, memory chips weren't socketed, so we had to
        have whole spare memory board.  Now we have SIMMs, so we mainly
        just need spare SIMMs.  We have two or three, I think.  That should
        be fine.

      memory board:  The first 128Meg of memory is socketed in the mother-
        board.  To expand beyond that, we have a memory board.  We haven't
        got any memory to put in it yet, and haven't budgetted for any yet.
        Getting a spare for this is probably not a priority.

     So basically, we'd need to budget money for a motherboard spare.  We
     should buy a cpu spare.  We should keep an eye out for good deals on
     other stuff.

(2) Continue using the 4/260 as a backup machine.

     This means staff needs to improve procedures for maintaining both the
     4/260 and 4/670 software suites.  In theory this shouldn't be too
     difficult, since the differ mainly in the kernels and in a few programs
     that interact closely with the kernel (like "ps").

response 2 of 37:

Nov 27 05:43 UTC 1997

I support the notion of parallel maintenance of both machines, especially
since it will be much simpler to do the same or similar changes on both
machines at one time (at the cost of a little extra time) than to try to play
catch-up in a crisis.  Some analysis and discussion to determine the
availability of the necessary time should take place, and if necessary, we
should consider adding more staff.  Certainly this scheme seems to make the
most sense until either we have the necessary parts or a greater sense of the
reliability of the current ones.

I'd like to learn more about programming in the unix environment, though my
background is fairly limited (old BASIC and HYPERTALK, the scripting language
for the Mac HyperCard program, with a very little introduction to HTML).
I've also dabbled with a little scripting in my home directory to facilitate
some frequently used commands...

response 4 of 37:

Nov 28 06:43 UTC 1997

understandably.  i just want to avoid taxing existing staff beyond burnout.
we place a lot of demands on them, and this is just another one...

response 6 of 37:

Dec 3 02:04 UTC 1997

I'd like to see enough spare hardware to keep the 670 running.  This means,
as Jan said, a spare motherboard, and a spare CPU.  We already have a spare
ALM, for when we will be using that, and a spare terminal server, for when
we will be using that.  Among other things, keeping the old computer in synch
as a hot backup makes it harder to use it for anything else, and I'd like to
see us use it for something.

response 8 of 37:

Dec 16 18:00 UTC 1997

SM100s should cost no more than $100, and could be $50 if you find a
deal.  Motherboards are a little hard to come by separately, but you
might find a good deal on a cheap system, if you keep up with Usenet
ads.

If you read Usenet through DejaNews, I'd suggest creating your filter
for the newsgroup misc.forsale.computers.workstation, covering the
last couple months, then for the subject search after creating the
filter, use "'600mp' or '630mp' or '670mp' or '690mp'" as search
criteria.  An example "package" deal listed from this June:

> Sun Sparcserver board out of a 670MP, includes 2 dual cpu
> boards (ross 40mhz) , GX framebuffer, 64 megs of ram, and
> keyboard & mouse.  I would like to get $750 for this.
>
> The case may be available with a 1gig drive and cdrom.

I'm sure we purchased a couple spare SIMMs before.  I reimbursed
Grex for the bad SM100 board, intending to return it, although
since I didn't, I'll give that back as a freebie...it did seem to work
in the 670 with only one functioning CPU, so it should work as a
hobble-along backup processor.  Stuff I've read says running two
SM100s (i.e. four processors, since each SM100 has two CPUs) with
SunOS is usually slower than using one SM100, though it depends on
the type of load on the system.

If you buy another processor, you may want to consider an SM41 or
SM51 (I've forgotten precisely what submodels are compatible with
SunOS), rather than an SM100...I think SM51s might be around
$150-200 each.

response 10 of 37:

Dec 17 20:32 UTC 1997

Right.  My memory of the bad SM100 was that the first CPU on it was bad.  The
4/600 boots up on the first CPU, and only starts using the second one later.
I think that means that we could not boot with the bad SM100 card as the only
CPU card.  However, the card may be repairable.  It could be something as
simple as a bad trace on the PC board.  Maybe someone who understands such
things can look at it.

I think Birdsall's Sun Hardware Reference says that SM41 and SM51 modules can
only be used with Solaris 2.something.  That means that to use those, we'd
have to upgrade from SunOS to Solaris.  This may be something we want to do
someday, but it won't be simple.

So I think we should stick with SM100's for now.

Steve Weiss recently ordered and installed another 16 4M memory chips for the
4/670.  It is now running on 128Meg of memory.

response 12 of 37:

Dec 20 04:01 UTC 1997

You can run SunOS 4.1.3 on SM41s and SM51s, but you need
boot PROMs of a certain version (2.8v2 for SM41s and 2.10
for Sm51s), and I'm not positive if you can run multiple
processors with those CPUs.  But having the same processor
module would be best for trouble-shooting, too.  I'll keep
a lookout for SM100s.

By the way, this is a hardly-related tangent other than
being hardware Grex might want, but the latest Corporate
Systems Center catalog (from which Grex got some 2 gig
HP drives) lists an 8.5 gig Micropolis for $300...5.25"
FH SCSI2, new w/warranty.  Seems like a decent deal.

response 14 of 37:

Dec 20 13:16 UTC 1997

Didn't know they were going under...that would explain the
decent price!  The catalog lists a one year warranty, but
not by whom.  You could ask CSC by phone (408.743.8770) or
check their web site (www.corpsys.com) for an e-mail address.

response 16 of 37:

Dec 27 23:00 UTC 1997

however, it sounds as if grex has already experienced two not-good
disk deals from micropolis - beware of the third?

response 20 of 37:

Jan 13 02:20 UTC 1998

Unless we get *really* good deals, such that using a backup is still
economical, then I don't mind patronizing Micropolis again.  Otherwise, let's
not bother with them.

response 22 of 37:

Mar 11 17:12 UTC 1998

I've replied to this in E-mail - yes, we'd be very interested.  We have
been planing to set up a mail machine and need a drive for it.

response 24 of 37:

Mar 12 00:29 UTC 1998

You're quite welcome.

I have used M-Net and Grex off and on since around 1985, though mostly
"off" these days.  The Altos was the first UNIX machine I ever used.
It's what prompted me to buy my first UNIX box, a firesale AT&T 3B1,
in 1987.  After having made my living doing UNIX and IP network admin
stuff for several years now I'm glad to be able to give something
back.  In 1985 I'm sure I would have seriously doubted that I'd ever
own a 1.2G drive, much less be giving one away.  It's a testament to
how far things have come since then.