I think I fixed the problem. I at least have mpirun ... hostname working over the cluster.
The first thing I needed to do was to make the gigabit network an internal zone in Yast ... firewall (which essentially turns off the firewall over this interface). Next I needed to add the -mca options as follows: mpirun --prefix /opt/openmpi -mca oob_tcp_include eth0 -mca btl_tcp_if_include eth0 --hostfile ~/work/openmpi_hostfile -np 4 hostname The above command works properly without the --prefix option, verifying that my PATH and LD_LIBRARY_PATH variables are properly set up. Unfortunately, I have jobs running on each machine in SMP mode that will take the better part of this coming week to complete, so it will be awhile before I will be able to do more than just mpirun ... hostname. Could a section be added to the FAQ mentioning that the firewall service should be shutdown over the mpi interface and that the two -mca switches should be used? This could perhaps be most useful to a beginner in either the 'Running MPI Jobs' or 'Troubleshooting' sections of the FAQ. Thanks, Mark Kosmowski
