Debian

The godfather of Linux distros

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Debian History

• Almost the oldest continuous Linux distribution - first release in September 1993
  • Slackware is slightly older with a first release in July 1993
  • Linux kernel was only introduced in 1991
• Named after founder Ian Murdock and his wife Debra (Deb-Ian)
• Current version is only 11.2, due to Debian’s slow and steady release cadence
• Very opinionated about software freedoms
• Basis for other well-known distros

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Debian Toy Story Version Naming

• Debian 1.x - Buzz, Rex, Bo
• Debian 2.x - Hamm, Slink, Potato
• Debian 3.x - Woody, Sarge
• Debian 4.0 - Etch
• Debian 5.0 - Lenny
• Debian 6.0 - Squeeze
• Debian 7 - Wheezy
• Debian 8 - Jessie
• Debian 9 - Stretch
• Debian 10 - Buster
• Debian 11 - Bullseye

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Debian Architectures

• armel / armhf / arm64
• i386 / amd64
• mips / mipsel / mips64el
• ppc64el / s390x

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Debian Software Packaging (by license)

• Repositories have grown from 500 packages in 1.x era to over 51,000 now
• Packages organized by three primary licensing schemes:
  • main - completely free software according to Debian guidelines
  • contrib - still free software, but has dependencies outside the Debian repos
  • non-free - software that is not under a free license

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Debian Software Packaging (by release cadence)

• Packages are part of several release streams
  • old stable - packages from the previous stable release
  • stable - packages from the current stable release
  • testing - packages that have sat in unstable for weeks with no major bugs filed
  • unstable - package updates that have just been submitted, and are believed to be ready for use
  • experimental - package version that are still incubating, and might require major changes, and coordination across maintainers
• unstable and testing are under increasing strict rules for new versions as the 2-3 year stable release cadence progresses

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Debian Software Packaging (tools)

• dpkg tool at the heart of everything
  • In its 3rd rewrite, shell -> Perl -> C
  • You’re probably having a weird day if using this is necessary
• apt-get, apt, aptitude, or Synaptic are more common front-ends to the dpkg tool
  • Package browsing and searching
  • Automated downloads
  • Dependency resolution

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Debian Software Packaging (frustrations)

• Strict adherence to licensing freedoms
• Separate package for each library
• Packages must be able to update themselves
• Often a maddening array of “supported” configurations
  • systemd vs sysvinit
  • kFreeBSD vs Linux
  • Desktop environments
• Very long release cycles

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Desktop Environments

Debian doesn’t like doing per-DE installers, and most notable desktop environments are packaged and selectable from a common installer:

• GNOME
• KDE
• Xfce
• LXDE
• MATE

Others packaged for later installation:

• Cinnamon, LXQt, Budgie, Enlightenment, FVWM-Crystal, GNUstep/Window Maker, Sugar Notion WM

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Derivatives

• Ubuntu
  • Clones Debian unstable at the start of every release cycle
  • Six month release cadence, long-term support edition every two years
  • Separate installers for different desktop environments
• Mint
  • Six month releases of their own packages, new Ubuntu core with each LTS
  • Only Cinnamon and MATE desktops supported
• Raspbian
  • Modified kernel/boot, and minimal desktop environment
• Kali, Tails, Pop!_OS, many, many others