On Dec 20, 2018, at 3:33 PM, Bob Beattie <b...@earth-alliance.co.uk> wrote:
> I'm working on OpenFOAM v5 and have been successful in getting two nodes 
> working together. (both 18.04 LTS connected via GbE)
> As both machines have a quad port gigabit NIC I have been trying to persuade 
> mpirun to use more than a single link on each machine for its communications, 
> but this has not been successful.

How are you measuring that it hasn't been successful?

By default, Open MPI's TCP BTL should utilize all the IP interfaces that it can 
find and are usable to reach peers.  E.g., if you have:

Machine A:


And machine B has similar interfaces (but .2 instead of .1), then Open MPI 
should automatically see / use them all.

One thing to make sure of is that you interfaces are on different subnets.  Bad 
Things(tm) can happen if you have multiple IP interfaces on the same subnet.  
It's technically allowed, but it's rarely what you actually want to do.

Jeff Squyres

users mailing list

Reply via email to