Cluster of 2 is setup “only” over InfiniBand (IPoIB) (no Ethernet configured). The IP communication like ping, ssh is functioning fine. Password-less ssh to node happening fine. When the command is given like: mpiexec.hydra -np 16 -iface ib0 -f cluster_list ./main.out -ppn 8 where cluster_list contains the lines node01 node02 we immediately get the following error: forrtl: severe (174): SIGSEGV, segmentation fault occurred However, if I comment “any one” node name in cluster_list file like: # node01 node02 or node01 # node02 or mpiexec.hydra -np 16 -iface ib0 -host node02 ./main.out -ppn 8 or mpiexec.hydra -np 16 -iface ib0 -host node01 ./main.out -ppn 8 and run the same command, we encounter “no errors” and the full runtime is achieved. My configuration ============= I’m using IPoIB only IB connection (Mellanox DDR HCA and SilverStorm Switch). Other application includes: Intel Fortran Composer XE 2013.3.163, Intel MPI 4.1.1.036, NetCDF 4.0.0, FFT 3.3.3, Intel OFED It is worth noting that only when two nodes provided, the error occurs. I can run mpiexec.hydra on one node (i.e. node01) and provide -host node02 in the command-line, and the process runs fine. Please provide your suggestion to eliminate this error. Thanks Girish Nair girish@njgroup.net (girish at njgroup dot net)
