Installing Fluka with Singularity

Fluka happens to be ultra compiler sensitive, and every new version comes with different demands on the compiler major and minor version. This is why we changed to a containarized installation based on Singularity. To install the image, Singularity must be installed on a host with sudo privileges. Also, two fluka**.tar.gz files are needed, which we can find here https://www.fluka.org/. It is a licensed software package, so to download the files credentials are needed which can be found the usual way (KeePass).

The image recipe should be reproducible for years, so we can make use of it for the next installations. Find it here= $USER/Easyconfig/uniol/f/fluka/fluka_2021.2-Singularity.def

Copy this and the tar-Files to your host system and procees with:

sudo singularity build fluka_2021.2-Singularity.simg fluka_2021.2-Singularity.def

Or if you want to change and edit some things inside the container before making a write-protected image, proceed as follows:

sudo singularity build --sandbox fluka_2021.2-Singularity.img fluka_2021.2-Singularity.def

#### if executed with sudo, singularity is not able to set up a display connection from image to your display!
#### for testing X11 capabilities, start singularity without sudo privileges! (exec or shell)
sudo singularity shell --writable fluka_2021.2-Singularity.img  # enter the image and do stuff

Finishing up...

sudo singularity build fluka_2021.2-Singularity.simg fluka_2021.2-Singularity.img

Afterwards, copy the final image with rsync -avzP to the software admin account on the cluster, and you're done!