====== Environment Modules ======

Environment modules are used to define environment variables for applications available on Magi. Formerly, we used **lmod**. We moved to **environment modules** in the current version of Magi. All modules are stored in /softs/modules.

In this directory, we find 4 subdirectories :
  * intel : Intel compiler's modules
  * slurm : SLURM job scheduler module
  * packages : Pre-compiled softwares (such as Matlab, CPLEX etc.)
  * compiled : Compiled software (such as OpenMPI, VASP etc.)

The **compiled** subdirectory reflects the way the software has been built. For instance, we have OpenMPI module located in gcc/10.2.1/openmpi/4.1.2 it means that OpenMPI version 4.1.2 has been compiled with gcc version 10.2.1.

To enable a module, for example OpenMPI, you use the **module** command with **load** :

   nicolas.greneche@magi3:~$ module load /softs/modules/compiled/gcc/10.2.1/openmpi/4.1.2

To list loaded modules :

   nicolas.greneche@magi3:~$ module list
   Currently Loaded Modulefiles:
    1) /softs/modules/slurm/21.08.5   2) /softs/modules/compiled/gcc/10.2.1/openmpi/4.1.2

To see all available modules :

   nicolas.greneche@magi3:~$ module av
   ------------------------------------------- /softs/modules/slurm -------------------------------
   21.08.5
   
   ------------------------------------------- /softs/modules/compiled ----------------------------
   gcc/10.2.1/openmpi/4.1.2(default)
   ...

And to unload a module :

   nicolas.greneche@magi3:~$ module unload /softs/modules/compiled/gcc/10.2.1/openmpi/4.1.2

The module is unloaded :

   nicolas.greneche@magi3:~$ module list
   Currently Loaded Modulefiles:
    1) /softs/modules/slurm/21.08.5

====== Upgrade from lmod to environment modules ======

You should modify your .bashrc to switch from **lmod** to **environement modules**. The .bashrc is located at the root of your home directory. For example, my .bashrc is in /home/dist/nicolas.greneche/.bashrc. For **lmod** you may find a section that looks like this :

   if [ -z "$BASHRC_READ" ]; then
      export BASHRC_READ=1
      module use /softs/modulefiles/Compiler
      module use /softs/modulefiles/Core
      module use /softs/modulefiles/MPI
      #Eventually, custom modules
   fi

You should replace this section with this one below :

   if [ -f /etc/profile.d/modules.sh ]
   then
      source /etc/profile.d/modules.sh
      export MODULEPATH=/softs/modules/slurm:/softs/modules/compiled:/softs/modules/intel:/softs/modules/packages
      # Enable some modules here
      module load /softs/modules/slurm/default
   fi

Then, you disconnect and reconnect to Magi and you should use **environment modules**.