### 3.1.2. Running Autodyn with Intel MPI

Intel MPI must be installed on each machine that will be used in the parallel processing environment by following the installation instructions for Intel MPI as provided in Setting up Distributed ANSYS. You may find it necessary to set the MPI password on each machine used. To do this, call `mpiexec` with the `-register` argument the first time you run `mpiexec`, entering your user password when prompted. This argument should be removed for subsequent parallel runs.

Note: The recommended method of running an Autodyn job using Intel MPI is by using the AUTODYNWRAPPER.exe file, which is described in Running Autodyn on Windows Platforms. The following is an alternative method of starting an Autodyn parallel job using Intel MPI. This method gives you the ability to add other Intel MPI options that are not supported by AUTODYNWRAPPER.exe.

Create a file called applfile, and in this file enter the following text, making the relevant changes for your parallel model, machine names, and installation path, should the installation not be in the default location:

    -localroot -env ANSYS_EXD_MPI_TYPE intelmpi -host [machinenameA] -np 1 –wdir "C:\Program Files\ANSYS Inc\v182\aisol\AUTODYN\winx64” autodyn.exe
    -host [machinenameB] -env ANSYS_EXD_MPI_TYPE intelmpi -np [number of slaves] "C:\Program Files\ANSYS Inc\v182\aisol\AUTODYN\winx64\adslave.exe"

The commands shown above will launch 1 master process on `machinenameA` and `number of slaves` slave processes on `machinenameB`. The working directory is specified by the `-wdir` option and should be modified if the installation of Autodyn is not in the default location.

Then start Autodyn using `mpiexec`. It is important that you reference the correct version of MPI, otherwise the wrong `mpiexec` command will be picked up from the path environment variable. You can reference the correct version of MPI by permanently setting the I_MPI_ROOT environment variable to point to latest supported version, or by temporarily changing it through a batch script.

To start Autodyn, create a batch file in the same application data directory as applfile file and execute it.

For example, create a blank file called autodyn_mpi.bat. In this file enter:

    set I_MPI_ROOT=%AWP_ROOT182%\commonfiles\MPI\Intel\4.1.3\winx64
    "%I_MPI_ROOT%\bin\mpiexec.exe" -configfile applfile

Once the batch file is executed, Autodyn starts, along with the number of slaves specified in applfile. You can now create your model or load an existing one and proceed with your analysis.

Release 18.2 - © ANSYS, Inc. All rights reserved.