[OMPI users] How to set parameters to utilize multiple network interfaces?

Hello, I am trying to run OpenMPI on AWSs new p4d instances. These instances have 4x 100Gb/s network interfaces, each with their own ipv4 address. I am primarily testing the bandwidth with the osu_micro_benchmarks test suite. Specifically I am running the osu_bibw and osu_mbw_mr tests to calculat

[OMPI users] Force TCP to go through network adapter for single-machine test.

I would like to test the network latency/bandwidth of each node that I am running on in parallel. I think the simplest way to do this would be to have each node test itself. My question is: How can I force all the OpenMPI TCP communication to go through the network adapter, and not use the optimiz