Hack 35 Convert Knoppix to Debian Unstable

Even though Knoppix is based on Debian, and the installation instructions help you install Knoppix on your hard drive, what you have installed is a hybrid Debian system. Here's how to convert a Knoppix install to as close to a standard Debian unstable branch distribution as you can get.

Knoppix is based on the Debian GNU/Linux distribution, but Knoppix uses a unique mix of packages from the stable, testing, and unstable branches, as well as from other unofficial Debian repositories. As a result, even if you select the Debian system install type, you won't get the same system as if you had installed Debian unstable from scratch. There are some steps you can perform, however, to get closer to a Debian unstable system.

The installation process for this system is almost exactly the same as for [Hack #33] . The only exception is that you select the Debian system type during configuration instead of beginner. Remember, with the Debian system type, Knoppix does not include its hardware-detection scripts in the install, so make sure that you have all of your hardware detected and configured before you start the install. In order to convert the install to Debian, the real work begins after the files have been copied, and you boot into the new system.

4.5.1 Configure APT

Once you boot into your new Knoppix install, you must change your Advanced Package Tool (APT) settings. APT is a management system for software packages. Under Debian, it provides a series of tools to ease installing, removing, and updating packages. The most commonly used APT tool is apt-get, which automates downloading packages and their dependencies for installation. When you tell apt-get to install a package, it finds the newest version of the package from its list of package repositories. Then it checks its local cache of packages, and if it does not have the package you need, it downloads the package and any dependencies directly from the repository. All of the configuration files for APT are located in the /etc/apt directory. The /etc/apt/sources.list file contains a list of all of the repositories the APT tool uses to look for packages. The /etc/apt/apt.conf file contains APT settings, such as which Debian branch to use by default.

The first step to convert Knoppix to Debian unstable is to edit /etc/apt/apt.conf as root, changing:

APT::Default-Release "testing";

to:

APT::Default-Release "unstable";

This setting controls which branch Debian defaults to when installing and upgrading packages. By changing testing to unstable, you tell Debian to upgrade any packages from the testing or stable repositories it might have installed to unstable at the next upgrade, and to default to installing from the unstable branch in the future.

The next step is to update the list of repositories APT uses by editing /etc/apt/sources.list as root. The default Knoppix sources.list file has sources for stable, testing, unstable, experimental, and a few other repositories. Comment all of the stable and testing repositories, which ensures that all our installs use the unstable packages. It is up to you if you wish to leave some of the other unofficial repositories in your sources.list. For a pure Debian Sid system, including non-us sources, delete all of the lines in your sources.list file, and edit it to look like this:

# Unstable

deb http://ftp.us.debian.org/debian unstable main contrib non-free

deb http://non-us.debian.org/debian-non-US unstable/non-US main contrib non-free



# Unstable Sources

deb-src http://ftp.us.debian.org/debian unstable main contrib non-free

deb-src http://non-us.debian.org/debian-non-US unstable/non-US main contrib non-free

Once you have edited your sources.list, update your system to unstable by running the following command as root:

root@ttyp0[knoppix]# apt-get update && apt-get dist-upgrade

This command downloads the latest list of packages from each source in your sources.list file, and then it upgrades the distribution to the very latest versions of each package. This ensures that old packages from stable or testing are replaced with packages from unstable.

As the packages install, you might be prompted that a configuration file for a package has been modified since installation. Chances are that Knoppix modified these configuration files to better suit your system, so it's safe to go with the default and keep the current version of the configuration file. Once this update has completed, your system should be up-to-date with the current Debian unstable.

As a final note, some packages on the Knoppix system come from other unofficial or experimental repositories, so there still might be a few packages on the system that can't be updated in this manner. Packages from the experimental repository, given time and testing, typically find their way into unstable. After using and updating your system, these packages should eventually sync up with unstable. In the case of packages from other sources (such as Java), you must decide whether to keep these repositories in your sources.list file, so the packages can be updated, or you must decide whether to leave these packages at their installed version by leaving out the repository.