A Short Tour of Linux Distributions

Transcript

1. A Short Tour of Linux
   Distributions
   Open Source 101, February 2017
   Tyler Langlois
   Infrastructure Engineer, Elastic
   

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2. $ whois tylerjl
   ● Infrastructure engineering/devops
   at Elastic
   ○ Operations and software dev
   ● Other pursuits
   ○ Linux package maintainer,
   functional programming,
   raspberry pi wrangler,
   automation
   normal
   person
   

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3. Who is This For?
   ● What’s a distribution?
   ● How are they different?
   ● Which should I
   choose?
   ● How should I choose?
   ● What’s happening in
   the distro landscape?
   

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4. Stay With Me, Here
   

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5. What’s a distribution?
   Version
   10
   8
   7
   Vista
   …
   Version
   Sierra
   El Capitan
   Yosemite
   ....
   

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6. What’s a distribution?
   Distribution
   

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7. What’s a distribution?
   Distribution
   Stable
   Testing
   Unstable (Sid)
   Version
   Jessie (8)
   Wheezy (7)
   …
   

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8. What’s a distribution?
   kernel
   Licensing
   Technology
   choices
   systemd
   rpm
   dpkg
   openrc
   Community
   GNU utilities
   

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9. What’s a distribution?
   Technology choices
   Package management
   ● apt, yum , pacman, portage
   Init system
   ● SysV, Upstart, systemd
   Other
   ● Desktop Environment
   ○ Gnome, KDE, xfce
   ● Defaults
   ○ filesystem, kernel patchsets
   ● Installer
   

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10. What’s a distribution?
    Technology choices: Package Management
    build
    $ conky
    ???
    

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11. What’s a distribution?
    Technology choices: Package Management
    $ apt install conky
    $ conky
    $ yum install conky
    $ conky
    $ pacman -S conky
    $ conky
    

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12. What’s a distribution?
    Technology choices: Package Management
    ● dpkg
    ○ Debian and all derivatives
    ○ .deb packages widely available
    ○ apt (formerly apt-get) CLI utility
    ● Features of note
    ○ dist-upgrade for easier
    major version updates
    ○ Ubuntu-created PPAs for small,
    third-party repos
    $ apt update
    $ apt upgrade
    $ apt search conky
    $ apt install conky
    

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13. What’s a distribution?
    Technology choices: Package Management
    ● rpm
    ○ Red Hat derivatives
    ○ .rpm shipped alongside .deb
    ○ yum, dnf most commonly used
    ● Features of note
    ○ Plugins like deltarpm improve
    performance
    ○ dnf next-gen yum replacement
    $ yum update
    $ yum search conky
    $ yum install conky
    

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14. What’s a distribution?
    Technology choices: Init Systems
    openrc
    sysv
    s6
    upstart
    runit
    systemd
    

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15. Distributions: Overview
    .rpm
    .deb
    

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16. Distributions: Overview
    Root distributions Derivatives
    + more!
    + more!
    deb
    rpm
    

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17. Debian
    Vital stats
    ● Governance
    ○ Community/constitution
    ● Tech
    ○ dpkg / apt / systemd
    ● Notes
    ○ Stability, open source
    ○ Bedrock for many .deb
    based distributions
    

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18. Debian
    Use Cases
    ● Rock-solid foundation for other projects (raspbian, Ubuntu, others)
    ● Stable branch is extremely stable, most users rely on
    testing/unstable
    ● No “flavors” of Debian per se, but equally capable for many roles
    ● Predictable cycle, stable releases are easy to test beforehand
    

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19. Ubuntu
    Vital stats
    ● Governance
    ○ Supported by Canonical
    ● Tech
    ○ dpkg / apt / systemd
    ● Notes
    ○ userbase, widespread
    adoption
    ○ Regular release cycle
    

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20. Ubuntu
    

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21. Use Cases
    ● Often the default choice for users who need general purpose distro
    ● For more specific purposes, Canonical ships more tuned releases
    ● Focus on user-friendly installation and experience
    ● Set-in-stone release cycle means predictable releases (+LTS)
    Ubuntu
    

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22. Linux Mint
    Vital stats
    ● Governance
    ○ Community distribution
    ● Notes
    ○ Very closely related to
    Ubuntu
    ○ Customized user interface
    and desktop experience
    ○ Ease-of-use and user
    friendliness
    

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23. Fedora
    Vital stats
    ● Governance
    ○ Community, sponsored by
    Red Hat
    ● Package management
    ○ rpm / dnf / systemd
    ● Notes
    ○ Strictly OSS
    ○ Cutting edge software
    ○ Spins
    

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24. RHEL
    Vital stats
    ● Governance
    ○ Red Hat, Inc.
    ● Package management
    ○ rpm / yum / systemd
    ● Notes
    ○ Enterprise-grade & industrial
    strength
    ○ Certifications & compliance
    ○ Commercial support
    

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25. CentOS
    Vital stats
    ● Governance
    ○ Community-driven, blessed
    by Red Hat
    ● Notes
    ○ It’s RHEL, but rebranded +
    free
    ○ Common base (for example,
    Amazon Linux)
    

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26. openSuSE + SLES
    Vital stats
    ● Governance
    ○ Commercial (SuSE)
    ● Tech
    ○ zypper / rpm / systemd
    ● Notes
    ○ OSS distro (openSuSE) and
    Enterprise (SLES)
    ○ Useful tools (YAST, btrfs)
    

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27. ...and so many more
    

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28. The “Other” Distros
    

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29. ● Most off-brand distributions are tuned to a specific use case
    ● All the exciting evolution happens at the fringes!
    What’s the Distinction?
    ● Nearly all distros branch off dpkg/rpm
    ● Package managers outside the norm grow a whole new ecosystem
    

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30. Arch
    Vital stats
    ● Governance
    ○ Community of trusted users
    ● Tech
    ○ pacman / systemd
    ● Notes
    ○ Simplicity
    ○ Vanilla software
    ○ Bleeding edge
    

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31. Use Cases
    ● pacman == yum == apt
    ● AUR is community-managed package repository
    ● Rolling updates means there are no “versions” of Arch
    ● Vanilla package a good base for derivative distributions
    ● Often a good choice if latest software is always needed
    Arch
    

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32. NixOS
    Vital stats
    ● Governance
    ○ Community (GitHub)
    ● Tech
    ○ nix / systemd
    ● Hallmarks
    ○ Declarative config
    ○ Atomic upgrades
    $ cat configuration.nix
    {
    virtualisation.docker.enable = true;
    }
    $ nixos-rebuild switch
    

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33. Gentoo
    Vital stats
    ● Governance
    ○ Community
    ● Tech
    ○ emerge / portage / openrc
    ● Hallmarks
    ○ From-source distro
    ○ Simplicity has spawned
    some other distros
    (including ChromeOS)
    

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34. Slackware
    Vital stats
    ● Governance
    ○ Community
    ● Tech
    ○ tarballs / BSD-SysV init
    ● Hallmarks
    ○ Oldest distribution still
    maintained
    ○ Simple package
    management
    

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35. Which Distro?
    

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36. Which Distro?
    Points to consider
    ● Stability versus latest features
    ○ Solid reliability takes years, it’s a tradeoff
    ○ Time-tested package managers (rpm, deb) are a safe bet
    ○ Users have a nice spectrum of latest-shipping distros (i.e., CentOS ->
    Fedora -> Arch)
    ○ Know your (eventual) upgrade plan (CentOS 6 -> 7???)
    

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37. Which Distro?
    Points to consider
    ● Stability versus latest features
    ● Machine use case
    ○ Servers
    ■ Stability, consistency, support considerations
    ■ CentOS, RHEL, Debian, Ubuntu LTS
    ○ Desktop
    ■ Graphics drivers, wireless drivers, etc.
    ○ Special-case
    ■ Kali, Vyatta, Raspbian, etc.
    

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38. Which Distro?
    Points to consider
    ● Stability versus latest features
    ● Machine use case
    ● Technology decisions
    ○ systemd-ocalypse
    ○ Preferred desktop environment
    ○ Defaults (filesystem, bootloader, and so on)
    ○ Kernel choices
    

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39. Which Distro?
    Points to consider
    ● Stability versus latest features
    ● Machine use case
    ● Technology decisions
    ● OSS versus commercial
    ○ How comfortable are you with a) community support, b) commercial
    support, c) do-it-yourself?
    ○ Licensing: are you compliant?
    ○ Free as in beer ≠ free as in speech
    

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40. The Future
    

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41. The Future
    ● btrfs and ZFS on Linux
    ○ btrfs
    ■ Native Linux filesystem
    ■ Rapidly stabilizing
    ○ ZFS
    ■ Adapted from Solaris
    ■ Long history
    ○ Copy-on-write
    ○ Online scrubbing
    ○ Snapshots
    Filesystems
    file.txt
    file.txt file.txt
    sda sdb pool
    

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42. The Future
    Distribution
    ● OSTree
    ○ Swap running operating system
    with new image
    ○ Similar strategy used in
    CoreOS
    ○ Experimental progress in
    Fedora
    v1 v2
    /root
    

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43. The Future
    Distribution
    Source: https://sourcediver.org/blog/2017/01/18/distributing-nixos-with-ipfs-part-1/
    

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44. The Future
    ● Wayland / Mir
    ○ Replacements for the venerable
    XFree86 / X.org
    ● Snappy
    ○ Ubuntu’s new packaging format
    ● dnf
    ○ Red Hat-based distribution
    next-gen yum
    ● Kernel
    ○ Live patching
    New Core Components
    

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45. Questions?
    

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46. Thank You!
    ● GitHub
    ○ tylerjl
    ● IRC, Twitter
    ○ leothrix
    ● tjll.net
    ● Check out “Open
    Source Developer’s
    Toolbox” later today
    

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