Obtaining CASA for Linux

Introduction

CASA is available for any interested user. You can find information about the software on http://casa.nrao.edu, including release notes and known issues.

To install CASA for Linux, we have packaged up a binary distribution of CASA which is available as a downloadable tar file. We believe this binary distribution works with most Linux distributions.

While the binary distribution is the only supported public distribution, most CASA developers use RPMs for many third-party packages installed with yum to do development on RedHat Enterprise Linux. Installing the developer RPMs requires root access and we only provide developer support for organizations which have a cooperative agreement to participate in the development of CASA.

We are currently working on the development of a distribution for developers similar to our standard binary distribution, but it is not yet ready for testing.

Installation

You do not have to have root or sudo permission, you can easily install CASA, delete it, move it, and it works for many versions of Linux.

The one caveat is that CASA on Linux currently will not run if the Security-Enhanced Linux option of the linux operating system is set to enforcing. For the non-root install to work. SElinux must be set to disabled or permissive (in /etc/selinux/config) or you must run (as root):

    setsebool -P allow_execheap=1 

Otherwise, you will encounter errors like:

    casapy: error while loading shared libraries: /opt/casa/casapy-20.0.5653-001/lib/liblapack.so.3.1.1:     cannot restore segment prot after reloc: Permission denied 

The non-root installation is thought to work on a wide variety of linux platforms including:

• RedHat Enterprise Linux: 4 & 5 (32 bit and 64 bit)
• Fedora Core Linux: 6, 7, 8 (32 bit and 64 bit)
• Ubuntu 8.0.4 (32 bit and 64 bit)
• openSUSE 10.0, 11.0 (32 bit and 64 bit)
• Debian 4.0 (32 bit and 64 bit)

and it may work for other versions of Linux. Please see our regression tables for a list of the platforms we test.

Unsupported platforms

The non-root install may work on other platforms not listed, please let us know if you find that this binary distribution of CASA works on other linux platforms.

Also note, that the plotting tasks like plotxy and plotcal are the ones that typically give problems for new platforms, so a check of these after attempting an unsupported platform installation is advisable.

Download & Unpack

You can download the distribution tar file from http://svn.cv.nrao.edu/casa/linux_distro.

This directory will contain two tar files one will be the 32-bit version of CASA and the other will be the 64-bit version of CASA. The file name of the 64-bit version ends with -64b.tar.gz.

After downloading the appropriate tar file, untar it with tar -zxf casapy-30.0.*.tar.gz. This will extract a directory with the same basename as the tar file. Change to that directory and add it to your path with, for example, PATH=`pwd`:$PATH. After that, you should be able to start CASA by running casapy.

If you encounter difficulties, please see our list of known problems.

Register for Support

If you would like to receive CASA support, please register for access to the NRAO Portal (my.nrao.edu). Registering will allow us to respond to defects and let you know when updates are available.

Developer Installation

Doing development in CASA currently requires root or sudo permission to install the prerequisite third party packages and it is only available for the versions of linux for which we have specifically built the necessary packages. Currently only RedHat Enterprise Linux:

• RHEL 4 (32 bit and 64 bit)
• RHEL 5 (32 bit and 64 bit)

Using Yum

We use yum to install and update the CASA RPMs. Yum is a package manager which downloads and installs CASA and all of its dependencies. See BuildingCasaLinux if you would like to see a list of its dependencies.

Update

If you have previously installed CASA using yum, you should be able to update to the most recent patch version by logging in as root and doing:

    yum update casapy 

or by running:

    sudo yum update casapy 

In the case of sudo, enter your UNIX password when prompted.

If you have not previously installed CASA or if the above update fails, continue reading...

Initial Install

You must either have the root password for your system or have sudo permissions to run commands as root.

We provide RPMs for RedHat Enterprise Linux (4 & 5), but this distribution has been used with success on Scientific Linux. 32 and 64 bit versions are available. If you try to install the 32 bit version on a 64 bit OS, you may run into dependency conflicts between the 32 bit versions of RPMs that CASA is linked against and pre-existing 64 bit RPMs already installed on your system.

On Linux we use yum to install and update CASA. To use yum, information about the CASA Linux repository must be added to yum's configuration. We have a bootstrap.linux script which adds this configuration information to yum. Although, yum is now part of the standard distribution of RedHat. This was not true for RedHat Enterprise Linux 4. For this version of Linux, the bootstrap.linux will both install yum and add the CASA Linux repository information.

To set up yum to install CASA for Linux, first fetch bootstrap.linux and make it executable by executing the following commands from the command line of a Linux terminal window:

   wget http://svn.cv.nrao.edu/casa/bootstrap.linux    chmod 755 bootstrap.linux 

To do the next part, you either have to be able to log in as root or be have permissions to use sudo. If you have the root password for your machine, do the following from the command line (entering the root password when prompted):

   su    ./bootstrap.linux    yum install casapy 

If you have sudo permissions, execute the following from the command line (entering your password when prompted):

   sudo ./bootstrap.linux    sudo yum install casapy

From this point on, you no longer need bootstrap.linux on the system on which you just installed CASA. Whenever you want to update to the most recent released version of CASA, either log in as root or use sudo to run:

   yum update casapy 

from the command line of a Linux terminal window.

-- DarrellSchiebel - 2009-06-17