The Lofar Login Environment (LLE)

This page describes the standard login environment for new users on the LOFAR cluster nodes. It can also be applied to accounts at the WRST site and on the Dwingeloo Linux systems.

Existing accounts can be easily modified; see below for a manual to do this.

The Lofar Login Environment sets a few things for your account, and allows you to easily initialise often used packages and tools at login time. To this purpose we provide a few simple standardized login-scripts.

To be able to use the LLE environment you must either use a (t)csh or bash login shell. We do not support scripts for any other shells.

If you have chosen for the (t)csh shell, you do as follows:

• Log in and go to your (empty) $HOME directory
• > ln -s /opt/login/cshrc .cshrc (Note: on lioffen you should refer to /app/login/cshrc !)
• Log out and login again; you should see a welcome message.

If you have chosen for the bash shell, you do as follows:

• Log in and go to your (empty) $HOME directory
• > ln -s /opt/login/bashrc .bashrc (Note: on lioffen you should refer to /app/login/cshrc !)
• Log out and login again; you should see a welcome message.

To use the LLE in an existing account, rename your existing .cshrc or .bashrc in your $HOME and follow the instructions given above.

Make sure that possibly existing files $HOME/.login, $HOME/.setenv and $HOME/.alias that you still want to use at login time are renamed to $HOME/.mylogin, $HOME/.mysetenv, $HOME/.myalias.

Some of the details are presented here.

The root directory for the scripts is provided in environment variable $APS_LOCAL, whose value is set in the cshrc or bashrc scripts. The actual value depends on your location:

• CEP processing cluster: /opt
• lioffen nodes: /app
• WSRT: /wop25_1/aps_local
• D'loo: /local

In directory ${APS_LOCAL}/login are a number of default login scripts. The scripts ending with .bash are for the bash shell, the others for the (t)csh shell:

• cshrc → sets APS_LOCAL and calls the other scripts
• login → Displays welcome message; no settings
• setenv → adds some items to $PATH, sets your prompt, etc.
• alias → some default aliases to make life easy
• setpackages → script to define packages to initialize at login-time

Users should NEVER modify these default scripts at this location!

Personal command aliases can be added to a file $HOME/.myalias. When this file exists, the .cshrc or .bashrc script will read this file after reading the default ${APS_LOCAL}/login/alias(.bash).

Personal extensions to $PATH, personal environment variables, personal prompt setting, or overloaded existing environment variables should be done in a file $HOME/.mysetenv. If this file exists, the cshrc or bashrc script will read this file.

To initialize the use of installed packages on your system you must create a file $HOME/.mypackages. If this file exists, it is used by the LLE script setpackages.

In the directory ${APS_LOCAL}/scripts you will find available package initialization scripts, named like do<package> (e.g., doCasacore, doPyrap). Whenever you add a package to the file $HOME/.mypackages, the associated script in $APS_LOCAL/scripts will be source'd.

The file $HOME/.mypackages can look like this:

Casacore
doPyrap

The packages can be on one line or on multiple lines. Also note the use of <package> and do<package>; both are accepted. If an initialization script cannot be found, it will be reported to the user.

Apart from the systemwide do<package> files provided in directory $APS_LOCAL/scripts, users can add their personal do<package> files in their $HOME and have these run at login time. If there is a do<package> file both in $HOME and in $APS_LOCAL/scripts, the version in $HOME has preference and will be executed. This can be used to test a different version of a package, etc… To add a new, personal, package, act as follows:

• Install the package
• Create a $HOME/do<package> initialization script (e.g., adding the installation directory to your $PATH)
• Add <package> to the list of packages in file $HOME/.mypackages

To start up an X environment you have to make sure that

• The files $HOME/.xinitrc and $HOME/.xsession are removed

Determine the colordepth that you need (8, 16, 24 bit display) and type:

  startx -- :1 -depth <colordepth>

This should start your X environment at the proper colordepth. This will create an additional X Server next to the one you are already running. You can access this with Alt-F8 or Cntl-Alt-F8. The F7 variant will give you back your normal X.

If you need help, or have questions, or want to give any other comments, contact Arno Schoenmakers or Adriaan Renting.

New do<xxxx>-files can be added at any time if you have a new package that is available systemwide. Contact Arno Schoenmakers or Adriaan Renting in this case.