[Beowulf] Re: how do I get started?

[Mark Kosmowski]

>>> Mark Kosmowski wrote:
>>>
>>> I have a small cluster too (ok, had, I'm condensing to one big RAM
>>> workstation at the moment).  Mine was a 3 node dual Opteron setup.
>>>
>>> The first trick is to get each node to be able to ssh to every other
>>> node without getting a password prompt.  It doesn't matter for the
>>> calculation whether this is done by passwordless ssh or using some
>>> keychain type applet.  All that matters for the calculation is that
>>> each node be able to ssh without prompt to each other node.  This
>>> means n! checks.  For my 3 node baby cluster I did this manually,
>>> since 3! is 6.  More nodes - might want to make a script or something.

Here is a link for the keychain script I mentioned earlier:

http://www.ibm.com/developerworks/library/l-keyc2/

>>>
>>>
>>>  Here is an example with one-lined "script" for the ssh password less
>>> logon:
>>>
>>>
>>> http://wiki.neuralbs.com/index.php/Howto_Build_a_Basic_Gentoo_Beowulf_Cluster#Passwordless_Logon_to_the_Nodes_and_Node_List_Creation
>>>
>>> Next, you need to make your application parellel.  This typically
>>> involves compiling with some sort of MPI.  I use OpenMPI.  MPICH is
>>> another option.  This is going to be part of the learning curve.  When
>>> you can <mpirun hostname> and get an output for each CPU (each core?)
>>> you're ready to start wrestling with an MPI compile of your
>>> application code.
>>>
>>> If you're not used to compiling your own code, there may be a bit of a
>>> learning curve for this also.
>>>
>>>
>>>  Well... once I "finish" my Google Summer of Code project, people like you
>>> will have a fun playground with graphical examples (as well as serious
>>> people for serious HPC...but they won't admit to that and keep using RH as
>>> an OS :P)
>>>
>>> http://soc.gentooexperimental.org/projects/show/gentoo-cluster-seed
>>>
>>> Good luck!
>>>
>>> Mark E. Kosmowski
>>>
>>>
>>>  Enjoy,
>>>
>>> Eric Thibodeau
>>>
>>>  Amir,
>>> Did you try any of the documents referenced at wiki,http://en.wikipedia.org/wiki/Beowulf_%28computing%29#See_also?
>>>
>>> There is a free downloadable book at Professor Brown's website, start athttp://www.phy.duke.edu/~rgb/Beowulf/beowulf.php <http://www.phy.duke.edu/%7Ergb/Beowulf/beowulf.php>
>>>
>>> And I believe yes, you can use SSH to replace RSH pretty much anywhere. I
>>> haven't done that myself but I'm only a hobbyist.
>>>
>>> Good luck,
>>> Peter
>>>
>>>
>>> On 7/16/08, Amir Saad <eng_amirsaad at yahoo.com> <eng_amirsaad at yahoo.com> wrote:
>>>
>>>
>>>  I'm trying to build a small Beowulf cluster using 5 Ubuntu machines. I did
>>> a lot of search and yet couldn't find a getting started guide. Any ideas?
>>>
>>> All the articles I found are using RSH, is it possible to replace this with
>>> password-less SSH? Would it be possible to use Ubuntu? Which packages should
>>> I install to build the cluster?
>>>
>>> Please advice.
>>>
>>> Thank you
>>>
>>> Amir