Hi Nils,
I think you can try the IMB test that is included in HPC-X that is in $HPCX_MPI_TESTS_DIR
mpirun -mca pml yalla -np 2 ${HPCX_MPI_TESTS_DIR}/imb/IMB-MPI1
Could it possibly be that there are other MPI libraries in your LD_LIBRARY_PATH?
Have you tried running 2 processes on a single node, and would that work?
