Re: no switch?

[Eray Ozkural <erayo@cs.bilkent.edu.tr>]

erasmo perez wrote:

hello

is it possible to link 2 machines in order to make a 2 machines
beowulf cluster but without a switch ?
 

Of course it's possible. Just connect two ethernets through a single UTP.
If you ask your hardware store how to do this, they'll give you two
eth cards
and a cable that does the job.
 
>  
> is is recomendable ? what about the latency times and collisions ?
Sure, it's recommendable, but it's good only for experimenting: not much
point in getting a 2 cluster. If you want to use it for processing
power, then
you should go for a dual board. Err, and you'll find out that a cluster
is good
only if you're using stuff meant for parallel machines, or if you need
to batch
process many serial jobs.  You may also find some kernel patches
useful.
For instance a certain patch gives you global PID's on the cluster
through a master node.

If you want low latency, you should get better network hardware, that easy.
By collision, do you mean eth collisions? You won't get much congestion when
you have just two nodes, so it's safe.

But if you're really considering it I recommend you to buy more than 4 nodes, that
will be a more sensible setup for beowulf, a 2 nodes beowulf is only useful
for practice. You can ask for more advice on what hardware to buy.
 

-- 
 ++++-+++-+++-++-++-++--+---+----+----- ---  --  -  - 
 +  Eray "eXa" Ozkural                   .      .   .  . . .
 +  CS, Bilkent University, Ankara             ^  .  o   .      .
 |  mail: erayo@cs.bilkent.edu.tr                .  ^  .   .