[luau] Re: Start the ball rolling

Wed Apr 30 01:10:04 PDT 2003

On Tue, 2003-04-29 at 11:04, Nakashima wrote:
> On Tue, 29 Apr 2003, Warren Togami wrote:
> > Are both schools a situation where you have a room that you want to
> > convert into a computer lab?
> 
> Both schools want an LTSP lab (25-30 thin clients). However, we would like
> to extend LTSP services to other locations also (classrooms, library,
> office, etc).
> 
> Is there a time where we can meet with someone to discuss options in
> detail? Our budgets are limited, we are not LTSP experts, and I would hate
> to make a poorly informed decision.
> 
> > Assuming we have enough suitable computers at Pricebusters that are
> > workable with LTSP,
> 
> We may have access to other sources.  We are certainly not in a rush to do
> this.  We want to do it "right" more than "quick." Liliuokalani is looking
> at a $1,500 budget next year, so they might be planning now for 2 years
> down the road. On the positive side, they just got 25 Pentium II 133's
> from Bank of Hawaii that they could use.

If the $1,500 is available entirely to this project, it wouldn't take
much more of community donations to make this possible.  We could
probably tap the school's PTA and solicit LUAU sources of some
donations.  I think we may be able to collect enough money from these
sources if the school has a firm commitment that they will use it if
they had the funds.

Commercial sources would be more likely to give if they realize the
tremendous amount of benefit possible with relatively little cost.

> 
> > the following would need to be purchased in order to make this happen.
> > (These are just recommendations based on my recent research.)
> >
> > http://www.micropro.com/syslist.htm?product=Servers&sub=AMD%20Opteron%20Servers
> > MicroVault 5002 Tower (roughly $2142 as spec'ed)
> > SILVER Service Plan (3 Years Labor, 1 Year Parts).
> > In-Win IW-Q2000 ATX Tower 300W P.S..
> > Upgrade from 300 to 400Watt Intel/AMD PS.
> > Enermax UC-8FAB 8cm Case Cooling Fan.
> > MSI K8D Master Dual AMD Opteron DDR200/266/333 G-bit LAN Video.
> > Two AMD Opteron 240 Server CPU.
> > Two 1GB PC2100 DDR266 ECC Registered.
> > Mitsumi 3.5" Floppy Disk Drive.
> > Two Fujitsu 36.7GB 10K-RPM Ultra320 MAP3367NP.
> > Adaptec 29320-R Ultra320 SCSI PCI-X Card.
> > 54X CD-ROM IDE Drive, Mitsumi CD-FX54.
> >
> > * This particular server is around the low end of what I would currently
> > recommend.  The key parts are the two mirroring SCSI drives, for fault
> > tolerance and extra speed.  This motherboard can accept up to 4 more
> > sticks of RAM, so you can gain extra performance in the next year's
> > budget with plenty of room for RAM.  (Supports up to 12GB of RAM total.)
> > * I am buying two of these servers for Mid-Pac soon.  One for e-mail,
> > another for LTSP server.
> 
> Will this server allow us to "grow?" Or is it limited in terms of the
> number of thin clients it can support? Would we need to buy one server for
> the lab, one server for the classrooms, one server for the library, etc?
> Is there a solution that would be more scalable? So many questions because
> we are so green at this.
> 

You can buy servers that are slightly cheaper than this, but you would
have less ability to grow.  I have *no idea* how many thin clients this
new server would support, I can only compare it to my existing LTSP
server.

Mid-Pac's current LTSP server:
2x 32bit 850MHz Pentium3 processors
2GB ECC Registered SDRAM (100MHz)
(2GB maximum RAM)
IDE hard drive

This sample server above:
2x 64bit 1.4GHz AMD Opteron 1MB L2 cache (Model 240)
2GB ECC Registered DDR SDRAM (266MHz)
(12GB maximum RAM)
SCSI hard drives

Mid-Pac's current LTSP server is slightly sluggish with the 22 clients,
but still plenty usable.  Generally the thin clients will always outlive
your server as the software becomes more bloated over time.  (Last
year's version of Linux was faster than this latest version with the
enhanced desktop stuff.)  The new server mentioned above is a MONSTER by
comparison.  I believe that after tweaking the operating system, it will
be significantly more powerful and able to support minimally 40 clients
comfortably.  Perhaps more.  I have no way of really knowing until the
new server is delivered to Mid-Pac in about 3 weeks.

I already plan on ordering additional RAM during the 2003-2004 budget
year in order to add more performance/capacity to this new server.  The
motherboard has 6 RAM slots, so I can go up to 6GB RAM total using the
relatively cheap 1GB RAM sticks (about $300 each).

I believe this server would be able to handle an entire classroom of 30
of LTSP thin clients, plus maybe a dozen thin clients going over the
network to other rooms on campus.  There however may be a problem in
high bandwidth use going over your campus network, because 8 thin
clients using full screen animation can easily saturate a 100mbit
network link.  There are also security implications of transmitting this
over your campus network rather than an isolated network segment for a
classroom LTSP lab.  Network utilization may be the largest bottleneck
in some areas!

One more comment about the processor.  The Opteron model 240 at 1.4GHz
is the slowest available, with the fastest 1.8GHz.  The 25% faster
processor rivals the high end Xeons and Itaniums in performance in many
benchmarks, but is considerably more expensive.  It would add about
$1,400 to the cost to buy two of the 244's instead of two 240's.  At
that price you would be almost be better off buying TWO servers of the
slower speed.

> > PXE bootable network cards
> > * There are several brands of these.  I myself have only tested and used
> > 3Com 3c905-TXM cards for Mid-Pac and St. John's labs.  You can find
> > these in many places all over the Internet.  They seem to have been
> > completely reliable for me so far.
> > We managed to buy these for about $20 each from an online vendor
> > before.  Your mileage may vary.
> 
> How many NICs in the server? One? Two? What about a gigabit NIC?
> 

That particular motherboard comes with one gigabit copper NIC.

> > Cheap Unmanaged Switches
> > * Mid-Pac used cheap SMC switches from CompUSA.  I took a gamble when
> > buying them because I had no idea if they would be reliable, but at $150
> > each at the time it didn't seem like much of a risk.  In maybe two
> > years, 1 of 3 broke, although that may have been because I dropped it.
> > =(
> 
> What about using one big switch like
> http://www.netgear.com/products/details/FS750.asp
> 

Wow, this one looks really good, well worth the cost if you can afford
it.

If you had this switch with gigabit copper uplink, all you would really
need is to add one or two more 100mbit NICs to the server to go to the
campus network.  I would need to explain more about network utilization
of LTSP later.

> > Cable... RJ45 ends... maybe RJ45 jackets
> > * If you are going to buy cable locally, check out Home Depot before
> > going to computer stores.  I heard that CompUSA's own tech people buy
> > cable from Home Depot a mile away to use at their jobs rather than get
> > it from their own stock.
> >
> > Altogether this would be maybe $3,000-4,000.
> 
> Thanks for all the info! Sorry again if my questions sound dumb.

=)

Warren Togami
warren at togami.com