Environment Modules (software)

Last updated
Environment Modules
Stable release
5.5.0 / November 11, 2024;2 months ago (2024-11-11)
Repository
Written in Tcl
Operating system Unix-like
License GNU General Public License#Version 2
Website modules.sourceforge.net

The Environment Modules system is a software tool to help users manage their Unix or Linux shell environment, by allowing groups of related environment-variable settings to be made or removed dynamically.

Contents

Development

Modules has been around since the early 1990s [1] and is used at some of the largest computer centers [2] to deploy multiple versions of different software tools to users. The National Energy Research Scientific Computing Center (NERSC) reports that they use Environment Modules to manage nearly all software. [3] Environment Modules is specified as a Baseline Configuration requirement of the DoD High Performance Computing Modernization Program (HPCMP) [4] Project Baseline Configuration [5] team for participating DoD Supercomputing Resource Centers (DSRCs).

Modulefiles

The modules system is based on modulefiles, [6] which specify groups of environment settings that need to be made together. Modulefiles can be installed in a central location for general use, or in a user directory for personal use. Environment Modules modulefiles are written in the Tcl (Tool Command Language) and are interpreted by the modulecmd program via the module [7] user interface.

The key advantage of Environment Modules is that it is shell independent and supports all major shells such as Bash (bash), KornShell (ksh), Z shell (zsh), Bourne shell (sh), tcsh, and C shell (csh). The second key advantage is that it allows to use multiple versions of the program or package from the same account by just loading proper module. Those two advantages were instrumental in making Environment Modules a part of most HPC cluster setups. It also inspired several alternative implementation such as lmod from University of Texas, which is written in Lua instead of Tcl.

Modulefiles are created on per application per version basis. They can be dynamically loaded, unloaded, or switched. Along with the capability of using multiple versions of the same software it also can be used to implement site policies regarding the access and use of applications.

Default modulefiles directory

The default modules search path is in a hidden configuration file you can display with:

$ cat${MODULESHOME}/init/.modulespath /etc/modulefiles # CentOS, Scientific Linux, RHEL/usr/local/Modules/modulefiles # Build from source default

The /etc/modulefiles directory used by some distributions (or any other directory) can be used after a build from source by modifying the ${MODULESHOME}/init/.modulespath file.

Add your own modules to the path

The ${MODULESHOME}/modulefiles/use.own module essentially performs these steps:

mkdir$HOME/privatemodules cp${MODULESHOME}/modulefiles/null$HOME/privatemodules moduleuse--append$HOME/privatemodules

Use a version file within a hierarchical organization

The commands in this section require read/write/execute access to the /etc/modulefiles directory. The $HOME/privatemodules or another directory can be used instead along with "module use --append" or modification of the configuration file specifying the default modules search path.

The default modulefiles directory is empty initially. Copy the null module to the default modulefiles directory to have it shown by "module avail". The following uses the null and module-info modules to show use of a version file within a hierarchical organization and their effect on module avail and module show:

mkdir/etc/modulefiles/test cp${MODULESHOME}/modulefiles/null/etc/modulefiles/test/2.0 cp${MODULESHOME}/modulefiles/module-info/etc/modulefiles/test/1.0 moduleavail moduleshowtest

Set the first version as the default:

echo'#%Module'>/etc/modulefiles/test/.version echo'set ModulesVersion "1.0"'>>/etc/modulefiles/test/.version moduleavail moduleshowtest moduleshowtest/2.0

Switch to the newer version as the default with:

rm/etc/modulefiles/test/.version echo'#%Module'>/etc/modulefiles/test/.version echo'set ModulesVersion "2.0"'>>/etc/modulefiles/test/.version moduleavail moduleshowtest

After the above following a fresh install from source you would see:

$ moduleavail  -------------------- /usr/local/Modules/3.2.10/modulefiles ---------------------dot         module-git  module-info modules     null        use.own------------------------------- /etc/modulefiles -------------------------------null              test/1.0          test/2.0(default)--------------------------- /home/user/privatemodules --------------------------null$ moduleshowtest-------------------------------------------------------------------/etc/modulefiles/test/2.0:module-whatis    does absolutely nothing -------------------------------------------------------------------$ moduleshowtest/1.0 -------------------------------------------------------------------/etc/modulefiles/test/1.0:module-whatis    returns all various module-info values +++ module-info +++++++++++++++++++++++++++++++flags                   = 2mode                    = displayname                    = test/1.0specified               = test/1.0shell                   = bashshelltype               = shversion                 = test/1.0user                    = advancedtrace                   = 0tracepat                = -.*symbols                 = *undef*+++ info ++++++++++++++++++++++++++++++++++++++hostname                = localhostlevel                   = 1loaded null             = 0library                 = /usr/local/lib/tcl8.6nameofexecutable        =sharedlibextension      = .sotclversion              = 8.6patchlevel              = 8.6.1+++++++++++++++++++++++++++++++++++++++++++++++-------------------------------------------------------------------

Automatic modules initialization

Environment Modules on Scientific Linux, CentOS, and Red Hat Enterprise Linux distributions in the environment-modules package include modules.csh and modules.sh scripts for the /etc/profile.d directory that make modules initialization part of the default shell initialization. One of the advantages of Environment Modules is a single modulefile that supports bash, ksh, zsh, sh as well as tcsh and csh shell users for environment setup and initialization. This makes managing complex environments a bit less complicated.

For a source build the automation for all users can be manually configured.

bash, ksh, zsh, sh automatic modules initialization

/etc/profile.d/modules.sh from the etc/global/profile.modules file in the 3.2.10 modules build directory.

trap""123case"$0"in-bash|bash|*/bash)./usr/local/Modules/default/init/bash;;-ksh|ksh|*/ksh)./usr/local/Modules/default/init/ksh;;-zsh|zsh|*/zsh)./usr/local/Modules/default/init/zsh;;*)./usr/local/Modules/default/init/sh;;# defaultesactrap123

Copy the etc/global/profile.modules file from the 3.2.10 modules build directory to the system initialization directory:

$ sudocpetc/global/profile.modules/etc/profile.d/modules.sh

Add a version 3.2.10 symbolic link for the above generic addresses:

$ cd/usr/local/Modules $ sudoln-sT3.2.10default

tcsh, csh automatic modules initialization

A /etc/profile.d/modules.csh symbolic link to the etc/global/profile.modules file in the 3.2.10 modules build directory can enable automatic modules initialization for these users.

Installing on Linux

yum and rpm

On Scientific Linux, CentOS, and RHEL distributions Environment Modules is in the environment-modules package which can be installed with:

sudoyuminstallenvironment-modules

Once installed the package information can be viewed with:

rpm-qienvironment-modules rpm-qlenvironment-modules

apt and dpkg

On Ubuntu or systems using apt-get, Environment Modules can be installed with:

sudoapt-getinstallenvironment-modules

Once installed the package information can be viewed with:

dpkg-Lenvironment-modules

Linux from source

Although installing from a Linux distributions repository using that distributions update manager is the easiest the software can be installed from source. Resolve dependencies is the most difficult task for an installation from source. The typical configure, make, install cycle can become painfully slow as each configure improvement reveals another dependency not available in your default environment. This section includes the steps to install the Environment Modules package on source including compiling the Tcl from source as a dependency. [8]

8.6.1 version of Tcl built from /usr/local/src

Although the PCLinuxOS 64-bit repositories include Tcl they do not include a development package with the configuration files required to build Environment Modules on Linux from source. Building Tcl from source will make the required files available. [9]

Extract source after downloading

cd/usr/local/src tar-xvzf~/Downloads/tcl8.6.1-src.tar.gz

Configure, make, install

cd/usr/local/src/tcl8.6.1 unix/configure make sudomakeinstall

3.2.10 version of modules built from /usr/local/src

Extract source after downloading

cd/usr/local/src tar-xvzf~/Downloads/modules-3.2.10.tar.gz

Configure, make, install

cd/usr/local/src/modules-3.2.10 CPPFLAGS="-DUSE_INTERP_ERRORLINE"./configure make sudomakeinstall

Related Research Articles

<span class="mw-page-title-main">Bash (Unix shell)</span> GNU replacement for the Bourne shell

In computing, Bash is an interactive command interpreter and command programming language developed for UNIX-like operating systems. Created in 1989 by Brian Fox for the GNU Project, it is supported by the Free Software Foundation and designed as a 100% free alternative for the Bourne shell (sh) and other proprietary Unix shells.

<span class="mw-page-title-main">Cygwin</span> Unix-like environment for Windows

Cygwin is a free and open-source Unix-like environment and command-line interface (CLI) for Microsoft Windows. The project also provides a software repository containing open-source packages. Cygwin allows source code for Unix-like operating systems to be compiled and run on Windows. Cygwin provides native integration of Windows-based applications.

<span class="mw-page-title-main">Shell script</span> Script written for the shell, or command line interpreter, of an operating system

A shell script is a computer program designed to be run by a Unix shell, a command-line interpreter. The various dialects of shell scripts are considered to be command languages. Typical operations performed by shell scripts include file manipulation, program execution, and printing text. A script which sets up the environment, runs the program, and does any necessary cleanup or logging, is called a wrapper.

<span class="mw-page-title-main">Unix shell</span> Command-line interpreter for Unix operating system

A Unix shell is a command-line interpreter or shell that provides a command line user interface for Unix-like operating systems. The shell is both an interactive command language and a scripting language, and is used by the operating system to control the execution of the system using shell scripts.

<span class="mw-page-title-main">Z shell</span> Unix shell

The Z shell (Zsh) is a Unix shell that can be used as an interactive login shell and as a command interpreter for shell scripting. Zsh is an extended Bourne shell with many improvements, including some features of Bash, ksh, and tcsh.

<span class="mw-page-title-main">GoboLinux</span> Linux distribution

GoboLinux is a Linux distribution whose most prominent feature is a reorganization of the traditional Linux file system. Rather than following the Filesystem Hierarchy Standard like most Unix-like systems, each program in a GoboLinux system has its own subdirectory tree, where all of its files may be found. Thus, a program "Foo" has all of its specific files and libraries in /Programs/Foo, under the corresponding version of this program at hand. For example, the commonly known GCC compiler suite version 8.1.0, would reside under the directory /Programs/GCC/8.1.0.

sudo Command on Unix systems to temporarily assume root privileges

sudo is a program for Unix-like computer operating systems that enables users to run programs with the security privileges of another user, by default the superuser. It originally stood for "superuser do", as that was all it did, and this remains its most common usage; however, the official Sudo project page lists it as "su 'do'". The current Linux manual pages for su define it as "substitute user", making the correct meaning of sudo "substitute user, do", because sudo can run a command as other users as well.

Maven is a build automation tool used primarily for Java projects. Maven can also be used to build and manage projects written in C#, Ruby, Scala, and other languages. The Maven project is hosted by The Apache Software Foundation, where it was formerly part of the Jakarta Project.

<span class="mw-page-title-main">Comparison of command shells</span>

A command shell is a command-line interface to interact with and manipulate a computer's operating system.

modprobe is a Linux program originally written by Rusty Russell and used to add a loadable kernel module to the Linux kernel or to remove a loadable kernel module from the kernel. It is commonly used indirectly: udev relies upon modprobe to load drivers for automatically detected hardware.

<span class="mw-page-title-main">MacPorts</span> Package Manager for macOS

MacPorts, formerly DarwinPorts, is a package manager for macOS and Darwin. It is an open-source software project that aims to simplify the installation of other open source software. It is similar in function to Fink and the BSD ports collections.

<span class="mw-page-title-main">Fish (Unix shell)</span> User-friendly interactive Unix shell

Fish is a Unix-like shell with a focus on interactivity and usability. Fish is designed to be feature-rich by default, rather than highly configurable. Fish is considered an exotic shell since it does not adhere to POSIX shell standards, at the discretion of its maintainers.

<span class="mw-page-title-main">CMake</span> Cross-platform build tool for configuring platform-specific builds

CMake is a free, cross-platform, software development tool for building applications via compiler-independent instructions. It also can automate testing, packaging and installation. It runs on a variety of platforms and supports many programming languages.

When installing a package on a Unix or Unix-like environment, a configure script is a shell script that generates build configuration files for a codebase to facilitate cross-platform support. It generates files tailoring for the host system – the environment on which the codebase is built and run.

NixOS is a free and open source Linux distribution based on the Nix package manager. NixOS uses an immutable design and an atomic update model. Its use of a declarative configuration system allows reproducibility and portability.

<span class="mw-page-title-main">Command-line interface</span> Computer interface that uses text

A command-line interface (CLI) is a means of interacting with a computer program by inputting lines of text called command lines. Command-line interfaces emerged in the mid-1960s, on computer terminals, as an interactive and more user-friendly alternative to the non-interactive mode available with punched cards.

cdist Software configuration management tool

cdist is a free software configuration management tool for Unix-like systems. It manages nodes over SSH using the Bourne Shell, and does not require any additional software to be installed on target nodes.

<span class="mw-page-title-main">Windows Subsystem for Linux</span> Feature for a Linux environment in Windows

Windows Subsystem for Linux (WSL) is a feature of Microsoft Windows that allows for using a Linux environment without the need for a separate virtual machine or dual booting. WSL is installed by default in Windows 11. In Windows 10, it can be installed either by joining the Windows Insider program or manually via Microsoft Store or Winget.

doas is a program to execute commands as another user. The system administrator can configure it to give specified users privileges to execute specified commands. It is free and open-source under the ISC license and available in Unix and Unix-like operating systems.

<span class="mw-page-title-main">Termux</span> Terminal emulator for Android

Termux is a free and open-source terminal emulator for Android which allows for running a Linux environment on an Android device. Termux installs a minimal base system automatically; additional packages are available using its package manager, based on Debian's.

References

  1. ↑ Furlani, John L. (September 30 – October 3, 1991). "Modules: Providing a Flexible User Environment" (PDF). Proceedings of the Fifth Large Installation Systems Administration Conference (LISA V). San Diego, CA: 141–152. Retrieved 9 February 2014.
  2. ↑ "NICS User Support Kraken Modules Description". The National Institute for Computational Sciences (NICS). Oak Ridge National Laboratory - Department of Energy. 22 May 2011. Archived from the original on 22 February 2014. Retrieved 9 February 2014.
  3. ↑ "NERSC Modules Software Environment". The National Energy Research Scientific Computing Center (NERSC). Office of Science - Department of Energy. 2014-02-07. Retrieved 19 February 2014.
  4. ↑ "Use of Modules for Accessing Multiple Versions of Software". Baseline Configuration. DoD High Performance Computing Modernization Program (HPCMP). 20 Mar 2008. Archived from the original on 22 February 2014. Retrieved 9 February 2014.
  5. ↑ "DoD High Performance Computing Modernization Program Baseline Configuration". Baseline Configuration. DoD High Performance Computing Modernization Program (HPCMP). Archived from the original on 22 February 2014. Retrieved 9 February 2014.
  6. ↑ John L. Furlani & Peter W. Osel (July 2009). "modulefile - files containing Tcl code for the Modules package". SourceForge. man page. Retrieved 9 February 2014.
  7. ↑ John L. Furlani & Peter W. Osel (July 2009). "module - command interface to the Modules package". SourceForge. man page. Retrieved 9 February 2014.
  8. ↑ http://nickgeoghegan.net/linux/installing-environment-modules
  9. ↑ "TCL - Browse /TCL at SourceForge.net".
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.