Old Scheme Modules

Software installations on the clusters span many applications, and many different version numbers of the same application. It is not possible (nor desirable) to use them all at the same time, since different versions of the same application may conflict with each other. In order to simplify the control of which application versions are available in a specific session, there is a system for loading and unloading ‘modules’ which activate and deactivate the relevant parts of your user session.

The main command for using this system is the module command. You can find a list of all its options by typing:

module --help

Below we listed the most commonly used options.

Which modules are currently loaded?

To see the modules currently active in your session, use the command:

module list

Which modules are available?

In order to see a complete list of available modules, issue the command:

module avail

The resulting list will contain module names conforming to the following pattern:

  • name of the module
  • /
  • version
  • (default) if default version

How to load a module

In order to make, for instance, the NetCDF library available issue the command:

module load netCDF

This will load the default NetCDF version. To load a specific version, just include the version after a slash:

module load netCDF/3.6.2

How to unload a module

Keeping with the above example, use the following command to unload the NetCDF module again:

module unload netcdf

Which version of a module is the default?

In order to see, for instance, which version of NetCDF is loaded by the module, use:

module show netcdf

This will show the version and path of the module.

How do I switch to a different version of a module?

Switching to another version is similar to loading a specific version. As an example, if you want to switch from the default (current) Intel compilers version to version 14.0, type:

module switch intel intel/14.0