[gridengine users] tight openmpi integration - how to alter hostnames for selected exechosts?

[Kevin.Buckley at ecs.vuw.ac.nz]

> So my basic question is "how to force tightly integrated openmpi to use
> a (sligthly) different set of hostnames so that the IB fabric is
> actually used ..."

OpenMPI should just pick the "best" interface topology, which in
your case, should be the IB.

The one time I have had issues with OpenMPI geting things wrong, was
in running a VM cluster which had both the "real" IP interfaces, which
I had configured and some "background VM-control" interfaces, which I
had not, though once I'd realised what was happening, it was a simple
case to defeat the "extra" network using command-line flags to the
mpirun invocation.

Having said that, if you also had a IPoIB network, it might be fun
to see which gets the nod!

-- 
Kevin M. Buckley                                  Room:  CO327
School of Engineering and                         Phone: +64 4 463 5971
 Computer Science
Victoria University of Wellington
New Zealand