On 09/27/2011 07:50 AM, Jeff Squyres wrote:
> On Sep 27, 2011, at 6:35 AM, Salvatore Podda wrote:
> 
>>      We would like to know if the ethernet interfaces play any role in the 
>> startup phase of an opempi job using InfiniBand
>> In this case, where we can found some literature on this topic?
> 
> Unfortunately, there's not a lot of docs about this other than people asking 
> questions on this list.
> 
> IP is used by default during Open MPI startup.  Specifically, it is used as 
> our "out of band" communication channel for things like stdin/stdout/stderr 
> redirection, launch command relaying, process control, etc.  The OOB channel 
> is also used by default for bootstrapping IB queue pairs.

To clarify, is IP/Ethernet required, or will IPoIB be used if it's
configured on the nodes? Would this make a difference.

Just curious,
Prentice

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