I tried disabling the firewall real quick and still got the same results.

Disabling a potential error source for trial and error is always a good thing to isolate a problem. However, at one point I got the following error: [proxy:0:1@Pi02] launch_procs (/home/pi/mpich2/mpich-3.1/src/pm/hydra/pm/pmiserv/pmip_cb.c:641): unable to change wdir to /home/pi/mpi_test (No such file or directory) So I scratched my head and wondered if it was something as silly as the fact that I was calling mpiexec from a directory that existed on Pi01 and not on the other three. I quickly created the same directory on the other three Pis and bam: pi@Pi01 ~/mpi_test $ mpiexec -f machinefile -n 4 hostname Pi01 Pi04 Pi03 Pi02 Was it really that simple? Thanks. Ken Yes, That *IS* possible ! :) As you mention it now - I had the same problem some years ago. Unfortunately I didn't remember in time sparing you from dealing with the same trouble. Ursula _______________________________________________ discuss mailing list [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss