Hello, Using today's SVN 1.4a1r19757
with MCA='--mca btl_openib_verbose 1 --mca btl openib,self --mca btl_openib_if_include "mlx4_0:1,mlx4_1:1"' ibstatus (OFED 1.3.1) gives: Infiniband device 'mlx4_0' port 1 status: default gid: fe80:0000:0000:0000:0003:ba00:0100:71a1 base lid: 0x2f sm lid: 0x1 state: 4: ACTIVE phys state: 5: LinkUp rate: 20 Gb/sec (4X DDR) Infiniband device 'mlx4_0' port 2 status: default gid: fe80:0000:0000:0000:0003:ba00:0100:71a2 base lid: 0x0 sm lid: 0x0 state: 1: DOWN phys state: 2: Polling rate: 10 Gb/sec (4X) Infiniband device 'mlx4_1' port 1 status: default gid: fe80:0000:0000:0000:0003:ba00:0100:70b9 base lid: 0x30 sm lid: 0x1 state: 4: ACTIVE phys state: 5: LinkUp rate: 20 Gb/sec (4X DDR) Infiniband device 'mlx4_1' port 2 status: default gid: fe80:0000:0000:0000:0003:ba00:0100:70ba base lid: 0x0 sm lid: 0x0 state: 1: DOWN phys state: 2: Polling rate: 10 Gb/sec (4X) OpenMPI says for a: mpirun --prefix /tools/openmpi/1.4a1r19757_svn/connectx/gcc64/4.1.2/openib/rh_EL_4/x86_64/xeon -x LD_LIBRARY_PATH --mca btl_openib_verbose 1 --mca btl openib,self --mca btl_openib_if_include "mlx4_0:1,mlx4_1:1" -np 4 -machinefile dhosts ./IMB-MPI1.openmpi -------------------------------------------------------------------------- WARNING: One or more nonexistent OpenFabrics devices/ports were specified: Host: r4450_3 MCA parameter: mca_btl_if_include Nonexistent entities: "mlx4_0:1,mlx4_1:1" These entities will be ignored. You can disable this warning by setting the btl_openib_warn_nonexistent_if MCA parameter to 0. -------------------------------------------------------------------------- Scali 5.6 works in dual-rail mode with this as does mvapich2-1.2rc2. What am I doing wrong, please? DM