Hi Vincent (and others), I just wanted to add my own two cents after having fairly recently recalled the relative complexity of creating diskless nodes 'by hand' a few years back and subsequently finding the wonderful simplicity of tools such as Warewulf (or Rocks). So, in the interest of providing more information to the discussion at hand, here's a bit more detail and other assorted thoughts:
>[From pauln] >.. my apologies in advance: >http://www.psc.edu/~pauln/Diskless_Boot_Howto.html While I think cfengine and custom scripts gives a ton of flexibility, I've found it much easier on our diskless clusters to use the Warewulf software ( http://www.warewulf-cluster.org/ ). It handles a lot of the behind-the-scenes dirty work for you (ie, making the RAM disks/tmpfs, configuring PXE & DHCP, etc.) and the people on the mailing list tend to be quick to respond to troubles with effective solutions. Also, it's actively supported by other people and it just makes life a lot easier, in my opinion. It isn't hard at all to tweak, either, and I'd happily go into more detail if you wish, but I'd really recommend a quick look through the website as well, just to get a rough idea of the process. Secondly, though I haven't used it myself, I recently spoke with a friend who was very knowledgeable about Rocks, which also has a diskless mode, I'm told. Here's the link for that: ( http://www.rocksclusters.org/ ) > Programming in MPI/SHMEM is by the way pretty retarded way to program. If ease-of-use and shared-memory style are more important to you than performance, you might be interested in checking out the "Cluster OpenMP" developments in the Intel compilers. http://cache-www.intel.com/cd/00/00/28/58/285865_285865.pdf The list even had a short discussion on it that if you missed starts here: http://beowulf.org/pipermail/beowulf/2006-May/thread.html#15543 > Shared memory programming is just *so superior* over that in terms of ease > for the programmer and it also means you can just recompile your code to > work on a quad opteron or 8 processor opteron without any need to strip > MPI commands. This is mostly an aside, but why would you need to strip MPI commands to run on a 4 or 8 processor system? Or a one processor system, for that matter. I agree shared memory methods are easier to program, but I almost never need to strip MPI commands from my programs. In the worst case, I may need to add/remove a flag at compile time and use #defines in the code, but whenever possible, I actually try to build a code with MPI libraries that has a switch ('-serial') to allow it to run in single-processor mode. It just calls different routines where communication would ordinarily be. It's nice, elegant, and probably makes some people gasp in horror because of a few checks the code needs to make which possibly impact performance in a negligible way, but it's certainly extremely handy when benchmarking and verifying results. Finally, going back to the beginning of the discussion, I'd just caution you about putting motherboards on a slab of wood in a garage. The filter might keep dust out of the garage, but other things always seem to manage to get into garages, and lots of creepy-crawly things love warmth and light - two things your system are bound to give off. :) Good luck and have fun, - Brian _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
