[mpich-discuss] How to specify which Ethernet / IP interface to use?

[Jonathon Anderson]

I'm trying to use mpich2 [1] on a cluster of compute nodes each of
which has two Ethernet interfaces: one, an encumbered public /
Internet interface, and another a private / intranet interface. mpich
is defaulting to trying to use the public interface, which then hangs
indefinitely with both nodes in my job stuck listening via UDP.

I experience the same behavior whether I use mpiexec or srun --mpi=pmi2.

How do I tell mpich which interface to use?

Thanks!

~jonathon


[1]: mpich-ofi-gnu9-ohpc-3.4.2-3.1.ohpc.2.4.x86_64