At 04:58 PM 8/27/2007, Robert G. Brown wrote:
On Mon, 27 Aug 2007, Jim Lux wrote:
And here's a challenge at the other end of the spectrum.
What's the lowest cost, simplest, closest to off the shelf way to
build a small network file server that can do DHCP/PXE booting,
etc. for a compact low power cluster. Something like a LinkSys
NSLU-2 (<$100 but you need to add a USB disk, and load a new
version of the OS that has dhcpd and tftpd) could probably do it,
but it would be nice to have an integrated solution.
An intriguing problem, but if you are serious I think you'll have to
specify your requirements and the relative weight assigned tradeoffs a
bit more carefully. USB flash >>is<< remarkably cheap nowadays
(although often slow unless you spend a bit more than the minimum) and
there are a variety of very small devices, e.g. phones and PDAs and
PDA-phones capable of running an OS, networking, and attaching a USB
device or a flash chip directly. Then there are Slugs, and then there
are micro-ATX form factor motherboards, and then there are chopped up
laptops.
e.g. my HTC Hermes (aka ATT 8525) cellphone has a 2GB microSD flash
(and 802.11 wireless, and windows as well.. maybe I can get MPI to
work? A cluster of cellphones?)
The idea is to have a low power demo cluster that isn't cobbled up
out of spare parts and mobos (as nifty as the various toolbox and
bento box clusters are).
And, having a SINGLE place for the one-true-copy of the code (e.g. a
network server) that also assigns IP addresses, etc. is a nice thing.
(one could otherwise just put a local copy of everything at each node on flash)
One CAN buy a variety of low cost PCs that run off 12V (i.e. intended
as CarPCs) with no hard disk, etc., usually based on one of Via's
offerings. I have a set of 4 of them here, for instance, and they are
a Via C3 mobo with a addon board that holds the 12V power supply and
two CF slots.
I've looked at the "stack o'laptops" (much like the very first demo
cluster, no?) but you're paying a lot for screens, keyboards, etc,
and besides laptops aren't the most rugged devices in the world.
Truthfully, I think that if one really pushed it, one could probably
build a 50 GB solid state device (no moving parts) inside one of the
small "paperback" portable USB disk enclosures like the one I have for
my laptop.
There are a number of new laptops that have no hard disk, only
flash. Samsung has one with 32GB, Sony has one with the same (Vaio
Type G), etc.
One could likely power it off of a USB cable or a small
wall-wart, and serve the disk either over ethernet or 802.11b. It's
pretty easy to find functional motherboards this size or smaller for
prices as low as $52:
ooh, but it's a mobo, and you need the rest of the hardware (PS, case, etc.)
Think in terms of running off a 12V (unregulated) supply..
But you're right, it's quite doable as a hacking project, for under a
kilobuck (to build a server+4nodes)
James Lux, P.E.
Spacecraft Radio Frequency Subsystems Group
Flight Communications Systems Section
Jet Propulsion Laboratory, Mail Stop 161-213
4800 Oak Grove Drive
Pasadena CA 91109
tel: (818)354-2075
fax: (818)393-6875
_______________________________________________
Beowulf mailing list, [email protected]
To change your subscription (digest mode or unsubscribe) visit
http://www.beowulf.org/mailman/listinfo/beowulf
