Hi. I do "mpirun -np 4 pvserver --client-host=xxx --use-offscreen-rendering", and connect a ParaView client viewer. I can see 4 nodes in the memory inspector, but when I start a python shell in ParaView, and do: from mpi4py import MPI print MPI.COMM_WORLD.Get_size() I get the answer 1. Shouldn't it be 4? Thanks. -jeff