<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;">Hi,<div> I am having a problem in running replica exchange simulation over multiple nodes. </div><div>To run the simulation for 16 replicas over two 8-core processors, I generated a hostfile as follows:</div><div> yethiraj30 slots=8 max_slots=8</div><div> yethiraj31 slots=8 max_slots=8</div><div><br></div><div>These two machines are intra-connected and I have installed openmpi </div><div>Then If I try to run the replica exchange simulation using the following command:</div><div>mpirun -np 16 --hostfile hostfile mdrun_4mpi -s topol_.tpr -multi 16 -replex 100 >& log_replica_test</div><div><br></div><div>But I find following error and mdrun does not proceed at all :</div><div><br></div><div><div>NNODES=16, MYRANK=0, HOSTNAME=yethiraj30</div><div>NNODES=16, MYRANK=1, HOSTNAME=yethiraj30</div><div>NNODES=16,
MYRANK=4, HOSTNAME=yethiraj30</div><div>NNODES=16, MYRANK=2, HOSTNAME=yethiraj30</div><div>NNODES=16, MYRANK=6, HOSTNAME=yethiraj30</div><div>NNODES=16, MYRANK=3, HOSTNAME=yethiraj30</div><div>NNODES=16, MYRANK=5, HOSTNAME=yethiraj30</div><div>NNODES=16, MYRANK=7, HOSTNAME=yethiraj30</div><div>[yethiraj30][[22604,1],0][btl_tcp_endpoint.c:636:mca_btl_tcp_endpoint_complete_connect] connect() to 192.168.0.31 failed: No route to host (113)</div><div>[yethiraj30][[22604,1],4][btl_tcp_endpoint.c:636:mca_btl_tcp_endpoint_complete_connect] connect() to 192.168.0.31 failed: No route to host (113)</div><div>[yethiraj30][[22604,1],6][btl_tcp_endpoint.c:636:mca_btl_tcp_endpoint_complete_connect] connect() to 192.168.0.31 failed: No route to host (113)</div><div>[yethiraj30][[22604,1],1][btl_tcp_endpoint.c:636:mca_btl_tcp_endpoint_complete_connect] connect() to 192.168.0.31 failed: No route to host
(113)</div><div>[yethiraj30][[22604,1],3][btl_tcp_endpoint.c:636:mca_btl_tcp_endpoint_complete_connect] connect() to 192.168.0.31 failed: No route to host (113)</div><div>[yethiraj30][[22604,1],2][btl_tcp_endpoint.c:636:mca_btl_tcp_endpoint_complete_connect] connect() to 192.168.0.31 failed: No route to host (113)</div><div>NNODES=16, MYRANK=10, HOSTNAME=yethiraj31</div><div>NNODES=16, MYRANK=12, HOSTNAME=yethiraj31</div></div><div><br></div><div>I am not sure how to resolve this issue. In general, I can go from one machine to another without any problem using ssh. But, when I am trying to run openmpi over both the machines, I get this error. Any help will be appreciated.</div><div><br></div><div>Jagannath</div><div><br></div></td></tr></table>