Call 
Walk-ins (closed temporarily)The module utility helps you identify software that is available on the system and then load compatible packages. It manages complex combinations of paths, variables, and dependencies so you can compile and run jobs efficiently and make the most of your allocation.
Some modules are loaded by default. To see which modules those are, run module list when you log in. Depending on the work you need to do, you can load additional modules or different modules, or you can create and save multiple customized environments as described below.
CAUTION: Do not use personalized start files to load environment modules; it can cause conflicts. Instead, set up any unique environments that you need as described in our Customized environments documentation. Use that approach to create and save different environments for various aspects of your work – one for model runs and another for data analysis, for example.
Essential module commands
Following are descriptions of commonly used module commands.
module av – Show which modules are available for use with the currently loaded compiler.
module help – List options and subcommands for the module utility; or specify a modulefile by name for help with an individual module.
module help module help netcdf
module list – List the modules that are loaded.
module load – Load the default version of a software package, or load a specified version.
module load modulefile_name module load modulefile_name/n.n.n
module purge – Unload all modules. Some users include this command in a batch script, followed by a sequence of module load commands to establish a customized environment for the job being submitted.
module spider – List all modules that exist on the system. This does not give you information on module dependencies or tell you which modules can be loaded without conflicts at that point. Output from this command is published on these web pages daily for easy reference when you are not logged in: Cheyenne and Casper.
module swap – Unload one module and load a different one. Example:
module swap netcdf pnetcdf
module unload – Unload the specified software package.
module unload modulefile_name
module whatis – Get a short description of a module.
Customized environments
If you have created your own environment or want to have multiple collections of modules for various tasks, you can save those customized environments for easy re-use.
To save a customized environment as your default environment, load the modules that you want to use, then simply run module save or module s.
module save
If you plan to set up additional custom environments for other needs, give each collection of modules a unique name.
module save environment_name
To see a list of your customized, saved environments, use module savelist.
module savelist
To use one of the custom environments from that list, use module restore, or module r, followed by the name.
module restore environment_name
To see which modules you've saved in a custom environment, use module describe as shown.
module describe environment_name
To remove a customized environment that you have saved:
- Change to your .lmod.d directory.
- List the files.
- Use rm to delete what you no longer need.
cd /glade/u/home/username/.lmod.d ls -l rm environment_name
To revise a customized environment:
- Restore (change to) that environment.
- Unload, load, or swap modules as needed.
- Save the environment as a default environment again with the same name.
module restore myenvironment module load additional_module module save myenvironment
The previously saved environment will be renamed automatically with the addition of a tilde (~). In the example just above, the previously saved environment would be renamed to myenvironment~.
Troubleshooting tips
Situation: You load a custom default module collection (for example, module restore myenvironment). You receive a warning similar to this:
Lmod Warning: The following modules have changed: pgi Lmod Warning: Please re-save this collection
What to do: “Re-save” the customized module collection by running module save and using the same environment name, as follows.
module save myenvironment