I am trying to run a test mpiHelloWorld program that simply initializes the MPI environment on all the nodes, prints the hostname and rank of each node in the MPI process group and exits.

I am using MPI 1.1.2 and am running 997 processes on 499 nodes (Nodes have 2 dual core CPUs).

I get the following error messages when I run my program as follows: mpirun -np 997 -bynode -hostfile nodelist /main/mpiHelloWorld
[0,1,380][btl_tcp_endpoint.c:572:mca_btl_tcp_endpoint_complete_connect] [0,1,142][btl_tcp_endpoint.c:572:mca_btl_tcp_endpoint_complete_connect] [0,1,140][btl_tcp_endpoint.c:572:mca_btl_tcp_endpoint_complete_connect] [0,1,390][btl_tcp_endpoint.c:572:mca_btl_tcp_endpoint_complete_connect] connect() failed with errno=113
connect() failed with errno=113connect() failed with errno=113connect() failed with errno=113[0,1,138][btl_tcp_endpoint.c:572:mca_btl_tcp_endpoint_complete_connect]
connect() failed with errno=113[0,1,384][btl_tcp_endpoint.c:572:mca_btl_tcp_endpoint_complete_connect] [0,1,144][btl_tcp_endpoint.c:572:mca_btl_tcp_endpoint_complete_connect] connect() failed with errno=113
[0,1,388][btl_tcp_endpoint.c:572:mca_btl_tcp_endpoint_complete_connect] connect() failed with errno=113[0,1,386][btl_tcp_endpoint.c:572:mca_btl_tcp_endpoint_complete_connect] connect() failed with errno=113
[0,1,139][btl_tcp_endpoint.c:572:mca_btl_tcp_endpoint_complete_connect] connect() failed with errno=113
connect() failed with errno=113

The main thing is that I get these error messages around 3-4 times out of 10 attempts with the rest all completing successfully. I have looked into the FAQs in detail and also checked the tcp btl settings but am not able to figure it out.

All the 499 nodes have only eth0 active and I get the error even when I run the following: mpirun -np 997 -bynode –hostfile nodelist --mca btl_tcp_if_include eth0 /main/mpiHelloWorld

I have attached the output of ompi_info —all.

The following is the output of /sbin/ifconfig on the node where I start the mpi process (it is one of the 499 nodes)

eth0      Link encap:Ethernet  HWaddr 00:03:25:44:8F:D6  
          inet addr:  Bcast:  Mask:
          RX packets:1978724556 errors:17 dropped:0 overruns:0 frame:17
          TX packets:1767028063 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:580938897359 (554026.5 Mb)  TX bytes:689318600552 (657385.4 Mb)
          Interrupt:22 Base address:0xc000

lo        Link encap:Local Loopback  
          inet addr:  Mask:
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:70560 errors:0 dropped:0 overruns:0 frame:0
          TX packets:70560 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:339687635 (323.9 Mb)  TX bytes:339687635 (323.9 Mb)

Kindly help.