MPICH2

Settings for MPICH2 daemon:

$ echo "MPD_SECRETWORD=XXX" > ~/.mpd.conf
$ chmod 600 ~/.mpd.conf

Script for running application:

NODES=`uniq < $OAR_NODEFILE | wc -l | tr -d ' '`
NPROCS=`wc -l < $OAR_NODEFILE | tr -d ' '`
mpdboot --rsh=ssh --totalnum=$NODES --file=$OAR_NODEFILE
sleep 1
mpirun -n $NPROCS path_to_executable

In MPICH2, you normally don't need to specify -machinefile explicitly for Grid5000 (OAR machinefiles are automatically read)