NERSCPowering Scientific Discovery for 50 Years

Lmod User Training, June 22, 2021

June 22, 2021

Date and Time: 10 am -12pm Pacific Time, Tuesday, June 22, 2021

Lmod is a Lua based module system that is a new implementation of environment-modules that supports both TCL and Lua modules. Environment Modules provide a convenient way to dynamically change users' environment (PATH, LD_LIBRARY_PATH) through modulefiles by using the module command. Lmod and environment-modules expose the module command that provides a very similar command line interface however there are many differences between the tools along with new features only supported by Lmod.

Lmod will be used on Perlmutter as the primary interface for interacting with module files. If you have used Cori, you will find a lot of similarities with environment-modules. This training will walk through the new features and usage with Lmod to help users with the transition as Perlmutter comes online for general use.

In this session, we will conduct a hands-on training using Lmod in a shifter container where we will present an overview of module command, writing Lua modulefiles and Lmod specific features. The training section is organized in four exercises as follows:

  • Exercise 1: Intro to module and ml command
  • Exercise 2: Module collection, Debugging modules, using Lmod spider
  • Exercise 3: Overview of Lua Modulefile functions
  • Exercise 4: Translating modulefile from TCL to LUA, shell script to modulefile

The training material is available at and we highly encourage you perform the exercises during this session.

Lmod is developed by Texas Advanced Computing Center (TACC). For more details on Lmod see paper Best practices for the deployment and management of production HPC clusters.


This event will be presented online only using Zoom. Please see below for remote connection information.


Please use this form to register. There is no registration fee.