Hi Ralph, I can recreate this failure, I think it caused by the fact that we do not open orted on the last node( also I didnt check it ), since np < number of hosts.
I used the falowing configure line ../configure --prefix=/home/USERS/lenny/OMPI_ORTE_TRUNK on OMPI 1.4a1r19522 Hope it helped. #mpirun -np 3 -H witch2 ./spawn_multiple Parent: 1 of 3, witch2 (1 in init) Parent: 0 of 3, witch2 (1 in init) Parent: 2 of 3, witch2 (1 in init) #mpirun -np 3 -H witch2,witch3 ./spawn_multiple Parent: 0 of 3, witch2 (0 in init) Parent: 2 of 3, witch2 (0 in init) Parent: 1 of 3, witch3 (0 in init) #mpirun -np 3 -H witch2,witch3,witch4 ./spawn_multiple Parent: 0 of 3, witch2 (0 in init) Parent: 1 of 3, witch3 (0 in init) Parent: 2 of 3, witch4 (0 in init) #mpirun -np 3 -H witch2,witch3,witch4,witch5 ./spawn_multiple Parent: 0 of 3, witch2 (0 in init) Parent: 1 of 3, witch3 (0 in init) Parent: 2 of 3, witch4 (0 in init) [witch1:04806] *** Process received signal *** [witch1:04806] Signal: Segmentation fault (11) [witch1:04806] Signal code: Address not mapped (1) [witch1:04806] Failing at address: 0x38 [witch1:04806] [ 0] /lib64/libpthread.so.0 [0x2af5324e9c10] [witch1:04806] [ 1] /home/USERS/lenny/OMPI_ORTE_TRUNK/lib/libopen-rte.so.0(orte_plm_base_app_report_launch+0x27a) [0x2af531de3dca] [witch1:04806] [ 2] /home/USERS/lenny/OMPI_ORTE_TRUNK/lib/libopen-pal.so.0 [0x2af531f161bb] [witch1:04806] [ 3] /home/USERS/lenny/OMPI_ORTE_TRUNK/bin/mpirun [0x40378f] [witch1:04806] [ 4] /home/USERS/lenny/OMPI_ORTE_TRUNK/lib/libopen-pal.so.0 [0x2af531f161bb] [witch1:04806] [ 5] /home/USERS/lenny/OMPI_ORTE_TRUNK/lib/libopen-pal.so.0(opal_progress+0x9e) [0x2af531f0bf5e] [witch1:04806] [ 6] /home/USERS/lenny/OMPI_ORTE_TRUNK/lib/libopen-rte.so.0(orte_trigger_event+0x44) [0x2af531dc6c84] [witch1:04806] [ 7] /home/USERS/lenny/OMPI_ORTE_TRUNK/lib/libopen-rte.so.0(orte_plm_base_app_report_launch+0x20b) [0x2af531de3d5b] [witch1:04806] [ 8] /home/USERS/lenny/OMPI_ORTE_TRUNK/lib/libopen-pal.so.0 [0x2af531f161bb] [witch1:04806] [ 9] /home/USERS/lenny/OMPI_ORTE_TRUNK/lib/libopen-pal.so.0(opal_progress+0x9e) [0x2af531f0bf5e] [witch1:04806] [10] /home/USERS/lenny/OMPI_ORTE_TRUNK/lib/libopen-rte.so.0(orte_plm_base_launch_apps+0x227) [0x2af531de47e7] [witch1:04806] [11] /home/USERS/lenny/OMPI_ORTE_TRUNK/lib/openmpi/mca_plm_rsh.so [0x2af532c38d3d] [witch1:04806] [12] /home/USERS/lenny/OMPI_ORTE_TRUNK/lib/libopen-rte.so.0(orte_plm_base_receive_process_msg+0x456) [0x2af531de3086] [witch1:04806] [13] /home/USERS/lenny/OMPI_ORTE_TRUNK/lib/libopen-pal.so.0 [0x2af531f161bb] [witch1:04806] [14] /home/USERS/lenny/OMPI_ORTE_TRUNK/bin/mpirun [0x4033bc] [witch1:04806] [15] /home/USERS/lenny/OMPI_ORTE_TRUNK/bin/mpirun [0x402c23] [witch1:04806] [16] /lib64/libc.so.6(__libc_start_main+0xf4) [0x2af532610154] [witch1:04806] [17] /home/USERS/lenny/OMPI_ORTE_TRUNK/bin/mpirun [0x402b79] [witch1:04806] *** End of error message *** Segmentation fault Lenny.
