# FAQ¶

Most things in Salvus are statically linked, except MPI, thus dynamic MPI libraries must be available. If these are not present, errors like the following happen:

error while loading shared libraries: libmpicxx.so.12: cannot
open shared object file: No such file or directory


On sites without central job submission system (thus usually single nodes), just let the Mondaic downloader also download MPI. It will but the MPI libraries in the lib/ folder and SalvusFlow will set the LD_LIBRARY_PATH accordingly when running Salvus.

For other sites, please load a suitable MPI module (see here for more details). In some cases the module system might not set the \$LD_LIBRARY_PATH - then it has to be done manually in the SalvusFlow config file for the corresponding site.

### Jupyter kernel dies¶

If you see the Jupyter notebook kernel dying when importing parts of Salvus make sure that you have a valid license and an active internet connection. If one of these is the issue, there should be an error message in the terminal that started Jupyter notebook. For technical reasons we cannot show this message in the Jupyter notebook.