OpenMPI - MPICH2 conflict us-west2 AMI

[stefna87]

Hello,

I noticed an issue with the us-west2 AMI (ami-04bedf34) where the mpirun/mpiexec is linking to openMPI while mpicc and mpif90 are linking to MPICH2. Should be an easy fix for the next AMI update!

• Stefan

[jtriley]

This will be fixed in the upcoming 14.04 AMIs. For now you can fix this by running the following commands as root and rebundle the AMI:

$ update-alternatives --config mpi
$ update-alternatives --config mpirun

Select either all openmpi or all mpich paths at the interactive prompts.

[alexbw]

Bump, status of 14.04 AMIs? Lots of apt-get installs are 404ing with 13...

[jmuhlich]

I wanted to mention, in case anyone searches for it, that this also causes issues with the AMI-provided mpi4py. If you try to run mpi4py code with mpirun, all of the processes think they are rank 0 due to the mpich2/openmpi mismatch between mpi4py's compiled libraries and mpirun. The fix is to either switch the mpirun alternative to mpich2, or switch mpi to openmpi and reinstall mpi4py.