MPI error Plumed 2.4 patched with GROMACS 2016.4

[Leon Cole]

Hey guys!

So I'm running a version of Plumed (2.4)+INDUS (a code for indirect Umbrella sampling) patched with GROMACS 2016.4. I had to revert back to these older versions as its what works with the INDUS code. However I'm getting and error when running this code:

gmx mdrun -s prd.tpr -o prd.trr -x prd.xtc -c prd.gro  -e prd.edr -g prd.log -plumed plumed_bias.dat

This is the error :

Program:     gmx mdrun, version 2016.4
Unknown exception:
(exception type: N15MpiCommunicator26MpiNotInitializedExceptionE)
MPI has not been initialized

Now Ik the error is essentially telling me that theres issues in MPI communication bw GROMACS and Plumed. Im not sure if its both or just one. I have tried checking if my plumed install has MPI support initialized with plumed --has-mpi, i dont get a false or true or anything printed out so I'll just assume it does not. I also realized i did not do DGMX_MPI=OFF when installing GROMACS. Kindly correct me if anything Ive just written is off or incorrect. I have a feeling I might have to do the whole compilation and installation again however my main question is, is there a way to get around this error without the need to potentially do a reinstall?

Thanks in advance !