A Short Tour of Linux Distributions

1. A Short Tour of Linux Distributions Open Source 101, February 2017 Tyler Langlois Infrastructure Engineer, Elastic
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
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?
4. Stay With Me, Here
5. What’s a distribution? Version 10 8 7 Vista … Version Sierra El Capitan Yosemite ....
6. What’s a distribution? Distribution
7. What’s a distribution? Distribution Stable Testing Unstable (Sid) Version Jessie (8) Wheezy (7) …
8. What’s a distribution? kernel Licensing Technology choices systemd rpm dpkg openrc Community GNU utilities
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
10. What’s a distribution? Technology choices: Package Management build $ conky ???
11. What’s a distribution? Technology choices: Package Management $ apt install conky $ conky $ yum install conky $ conky $ pacman -S conky $ conky
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
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
14. What’s a distribution? Technology choices: Init Systems openrc sysv s6 upstart runit systemd
15. Distributions: Overview .rpm .deb
16. Distributions: Overview Root distributions Derivatives + more! + more! deb rpm
17. Debian Vital stats • Governance ◦ Community/constitution • Tech ◦ dpkg / apt / systemd • Notes ◦ Stability, open source ◦ Bedrock for many .deb based distributions
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
19. Ubuntu Vital stats • Governance ◦ Supported by Canonical • Tech ◦ dpkg / apt / systemd • Notes ◦ userbase, widespread adoption ◦ Regular release cycle
20. Ubuntu
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
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
23. Fedora Vital stats • Governance ◦ Community, sponsored by Red Hat • Package management ◦ rpm / dnf / systemd • Notes ◦ Strictly OSS ◦ Cutting edge software ◦ Spins
24. RHEL Vital stats • Governance ◦ Red Hat, Inc. • Package management ◦ rpm / yum / systemd • Notes ◦ Enterprise-grade & industrial strength ◦ Certifications & compliance ◦ Commercial support
25. CentOS Vital stats • Governance ◦ Community-driven, blessed by Red Hat • Notes ◦ It’s RHEL, but rebranded + free ◦ Common base (for example, Amazon Linux)
26. openSuSE + SLES Vital stats • Governance ◦ Commercial (SuSE) • Tech ◦ zypper / rpm / systemd • Notes ◦ OSS distro (openSuSE) and Enterprise (SLES) ◦ Useful tools (YAST, btrfs)
27. ...and so many more
28. The “Other” Distros
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
30. Arch Vital stats • Governance ◦ Community of trusted users • Tech ◦ pacman / systemd • Notes ◦ Simplicity ◦ Vanilla software ◦ Bleeding edge
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
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
33. Gentoo Vital stats • Governance ◦ Community • Tech ◦ emerge / portage / openrc • Hallmarks ◦ From-source distro ◦ Simplicity has spawned some other distros (including ChromeOS)
34. Slackware Vital stats • Governance ◦ Community • Tech ◦ tarballs / BSD-SysV init • Hallmarks ◦ Oldest distribution still maintained ◦ Simple package management
35. Which Distro?
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???)
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.
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
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
40. The Future
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
42. The Future Distribution • OSTree ◦ Swap running operating system with new image ◦ Similar strategy used in CoreOS ◦ Experimental progress in Fedora v1 v2 /root
43. The Future Distribution Source: https://sourcediver.org/blog/2017/01/18/distributing-nixos-with-ipfs-part-1/
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
45. Questions?
46. Thank You! • GitHub ◦ tylerjl • IRC, Twitter ◦ leothrix • tjll.net • Check out “Open Source Developer’s Toolbox” later today