Remixing Fedora 7

Fedora™ 7 hits the streets on May 31st. One of the most exciting features of the Fedora 7 release is the fact that users can remix the Fedora code in any variety of ways. Tools are provided that allow the user to build either a customized LiveCD or installable ISO, and to reach out to any 3rd-party RPM repositories and pull in packages from them at compose time.

First, the definition of a few terms:

• Repository — a collection of RPMs that live at a particular URL. These RPMs are available for install on a system.
• Distribution — A large number of RPMs, coming from potentially multiple repositories, that have been composed together to form a working system.
• Compose — the act of (and tools required for) taking RPMs from various repositories and turning them into a distribution.

The remainder of this article discusses three tools: Pungi, a command line tool used for building an installable ISO; LiveCD Creator, a command line tool used for building various “live” images; and Revisor, a graphical “wizard-like” program for building both installable ISOs and live ISOs, which uses the first two tools as its base.

Pungi

What is it?

Pungi is the Fedora Project’s compose tool. It is the code that takes RPMs from various repositories (including the Fedora repository) and turns those RPMs into a distribution that can actually be installed, usually by creating an ISO out of the RPMs that can in turn be burned onto a CD or DVD. Pungi’s home page has a more detailed description.

How is it installed?

The easiest way to get pungi is to run yum install pungi on your Fedora Core 6, Fedora 7 or Rawhide system, and the code will be installed from the Fedora repository.

How is it used?

Pungi is a command-line tool that is used for creating Fedora spins. It’s the tool that Fedora’s release engineering team is using to build the “official” Fedora 7 versions that will be released to the world, and the beauty of the tool is that since it is Free software, anyone else can use it to build their own custom version of Fedora as well.

This article does not delve too deeply into the specifics, because pungi is well-documented. If you can write a kickstart file, you can create a custom spin of Fedora using Pungi.

Once you have the RPM installed on your system, open up /etc/pungi/README or browse the online documentation, and go from there.

The basic steps that you will follow are:

• Configure /etc/pungi/pungi.conf as needed.
• Execute the command pungi, which will look to /etc/pungi/pungi.conf by default. Or run pungi --help to see some of the other options.

From there, pungi itself will go through the steps of downloading the RPMs you have requested from their repositories, figuring out how to break them up among various CDs (if it cannot fit on only one), and finally building the install tree and ISOs.

LiveCD Creator

What is it?

LiveCD Creator is aptly named, as it is the Fedora Project’s primary tool for the creation of “live” images. What happens to that image after its creation is up to the user — it can be burned to a CD or DVD, depending on size, or transferred onto a USB key, thereby making a custom mix of Fedora truly portable. The use case is compelling — a bootable USB key with a custom version of Fedora on part of it and personal data on the remaining free space. Plug that into any computer, boot, and your desktop follows you around.

How is it installed?

The easiest way to get pungi is to run yum install livecd-tools on your Fedora Core 6, Fedora 7 or Rawhide system, and the code will be installed from the Fedora repository.

How is it used?

A good overview of LiveCD Creator is available on the Fedora Project wiki. The basic options are quite simple to use, and is similar to pungi, since both use a kickstart-like file as the basis of the configuration.

The tool is more or less self-documenting, so livecd-creator –help will actually provide the user with a significant amount of information.

Revisor

What is it?

Revisor is the piece de resistance of the Fedora remixing tools. Using the Application Programming Interface (API) provided by Pungi and LiveCD Creator, Revisor is able to present the functionality of those two command line tools with a graphical front-end.

How is it installed?

Revisor will be in the Fedora repositories very soon. Until then, the RPM and md5sum are available from people.redhat.com.

How is it used?

There is some documentation available that goes into detail, but here’s a brief look:

Start Revisor by going to the application menu in your desktop, and selecting Revisor from the System Tools menu. You will be prompted for the root password.

From here on, pictures can do the talking:

This is what Revisor looks like at startup time.

Choose the media types that Revisor should produce.

Tell Revisor what repositories to use.

Select the packages that go on your custom spin.

Revisor allows you to specify configuration options similar to the installer.

Conclusion

There are three tools available for building custom respins of Fedora. Pungi is the command-line tool for building installable spins. LiveCD Creator is the command-line tool for building “live” spins. And Revisor is the graphical tool that builds on top of those two tools and gives the process a simple GUI.

So go forth and mix your own Fedora. And then come back and share it with us, and we’ll put it up on the Fedora website for others to use also.

This entry was posted by Max Spevack on Thursday, May 31st, 2007 at 7:42 am and is filed under Fedora. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.