Dear Srihari, From your email you seem to be exactly running mpirun -np 4 $<path to solver>/IncNavierStokesSolver file.xml’ However you have to replace $<path to solver> with the path to here you have placed the solver, i.e. something like mpirun -np 4 ~/Nektarpp/builds/dist/bin/IncNavierStokesSolver file.xml To see what is the directory of the path go to where the solver is located and type ‘pwd’ Regards, Spencer. On 12 Mar 2020, at 17:28, Srihari Menon <srimenon@seas.upenn.edu<mailto:srimenon@seas.upenn.edu>> wrote: This email from srimenon@seas.upenn.edu<mailto:srimenon@seas.upenn.edu> originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list<https://spam.ic.ac.uk/SpamConsole/Senders.aspx> to disable email stamping for this address. Hello all! I'm new to Nektar and have been trying to solve for incompressible flow using the MPI parallelisation feature. Problem: I run the command 'mpirun -np 4 $<path to solver>/IncNavierStokesSolver file.xml' and it does not work at all. No error no solver initialization. On running the same command with one modification 'mpirun -np 4 \$<path to solver>/IncNavierStokesSolver file.xml' the following error is encountered: -------------------------------------------------------------------------- mpirun was unable to launch the specified application as it could not access or execute an executable: Executable: \<path to solver>/IncNavierStokesSolver Node:XYZ while attempting to start process rank 0. -------------------------------------------------------------------------- 4 total processes failed to start Background: I am certain the server I work on has MPI enabled on it. When configuring the nektar package I switch the NEKTAR_USE_MPI to ON, and leave everything else as is, then install the make. I am also certain the file I'm trying to solve parallely works serially. I am not even being able to parallely execute standard files like Cyl.xml in the Examples of IncNavierStokesSovler. Following is my ccmake configuration list for reference. What am I doing wrong? Kindly advise. Thank you! Regards, Srihari Menon University of Pennsylvania Configuration list: CMAKE_BUILD_TYPE Release CMAKE_INSTALL_PREFIX /home1/s/srimenon/nektar++-4.4.1/build/dist CONVERT /usr/bin/convert NEKTAR_BUILD_DEMOS ON NEKTAR_BUILD_DOC OFF NEKTAR_BUILD_LIBRARY ON NEKTAR_BUILD_SOLVERS ON NEKTAR_BUILD_TESTS ON NEKTAR_BUILD_TIMINGS OFF NEKTAR_BUILD_UNIT_TESTS ON NEKTAR_BUILD_UTILITIES ON NEKTAR_SOLVER_ADR ON NEKTAR_SOLVER_APE ON NEKTAR_SOLVER_CARDIAC_EP ON NEKTAR_SOLVER_COMPRESSIBLE_FLO ON NEKTAR_SOLVER_DIFFUSION ON NEKTAR_SOLVER_ELASTICITY ON NEKTAR_SOLVER_INCNAVIERSTOKES ON NEKTAR_SOLVER_PULSEWAVE ON NEKTAR_SOLVER_SHALLOW_WATER ON NEKTAR_TEST_ALL OFF NEKTAR_TEST_FORCEMPIEXEC OFF NEKTAR_TEST_USE_HOSTFILE OFF NEKTAR_USE_ACML OFF NEKTAR_USE_ARPACK OFF NEKTAR_USE_BLAS_LAPACK ON NEKTAR_USE_CCM OFF NEKTAR_USE_FFTW OFF NEKTAR_USE_HDF5 OFF NEKTAR_USE_MESHGEN OFF NEKTAR_USE_MKL OFF NEKTAR_USE_MPI ON NEKTAR_USE_OPENBLAS ON NEKTAR_USE_PETSC OFF NEKTAR_USE_SCOTCH OFF NEKTAR_USE_SMV OFF NEKTAR_USE_VTK OFF THIRDPARTY_BUILD_BLAS_LAPACK ON THIRDPARTY_BUILD_BOOST ON THIRDPARTY_BUILD_GSMPI ON THIRDPARTY_BUILD_LOKI ON _______________________________________________ Nektar-users mailing list Nektar-users@imperial.ac.uk<mailto:Nektar-users@imperial.ac.uk> https://mailman.ic.ac.uk/mailman/listinfo/nektar-users Spencer Sherwin FREng, FRAeS Head of Aerodynamics Section, Director of Research Computing Service, Professor of Computational Fluid Mechanics, Department of Aeronautics, s.sherwin@imperial.ac.uk<mailto:s.sherwin@imperial.ac.uk> South Kensington Campus, Phone: +44 (0)20 7594 5052 Imperial College London, Fax: +44 (0)20 7594 1974 London, SW7 2AZ, UK http://www.imperial.ac.uk/people/s.sherwin/