Cygwin Error : tcp_peer_send_blocking: send() to socket

Question

My Cygwin installed on Windows 7 was working properly till I try to install a new package. The package installation failed. Then I keep getting this error every time I want to run my Open MPI program. I can successfully compile the program but cannot run it. I even remove and make a new installation without success.

Thanks for any hints. Below is the sample error message.

[Reloaded-PC:03900] [[3921,1],0] tcp_peer_send_blocking: send() to socket 13 failed: Transport endpoint is not connected (128)

[Reloaded-PC:03900] [[3921,1],0] tcp_peer_send_blocking: send() to socket 13 failed: Transport endpoint is not connected (128)

[Reloaded-PC:04676] [[3921,1],2] tcp_peer_send_blocking: send() to socket 13 failed: Transport endpoint is not connected (128)

[Reloaded-PC:04676] [[3921,1],2] tcp_peer_send_blocking: send() to socket 13 failed: Transport endpoint is not connected (128)

Answer 1

The problem is solved by disabling the unused network adapter in "Control Panel->Network and Internet->Network Connections".

It turned out the unused network adapter tried to get configured by DHCP and an IP address started with "169.254.X.X" was assigned to this adapter when DHCP fails. Somehow openmpi on Cygwin use that invalid IP address for establishing communication between processes.

I figured it out by looking at /tmp/openmpi-sessions-{username}/{PID of orterun}/contact.txt.