I get the failure messages, unfortunately:
I actually had attempted to call setgid from within the application previously, which looks similar to what you've done, but it failed. That was when I initiated the post to the mailing list. My conclusion, a guess really, was that Linux would not let me setgid from within my program because I was not root.
From: users-bounces_at_[hidden] [mailto:users-bounces_at_[hidden]] On Behalf Of Ralph Castain
Sent: Wednesday, September 14, 2011 8:15 AM
To: Open MPI Users
Subject: Re: [OMPI users] EXTERNAL: Re: Can you set the gid of the processes created by mpirun?
The attached should set the gid of the remote daemons (and their children) to the gid of mpirun. No cmd line option or anything is required - it will just always do it.
Would you mind giving it a try?
Please let me know if/how it works.