Frequently Asked Question

What other init systems exist besides systemd?

systemd, written by Lennart Poettering and Kay Sievers and first released in 2010, is now the init system on virtually every mainstream Linux distribution: Debian, Ubuntu, Fedora, RHEL, openSUSE, Arch. It is more than an init: it is a service manager, logger (journald), network configurator (networkd), DNS resolver (resolved), boot manager (systemd-boot), and much else. Its breadth has made it both extremely capable and, for some, controversial.

Alternatives still exist for users and distributions that prefer something smaller or more Unix-traditional. OpenRC is the default on Gentoo and Alpine, a dependency-based init that runs shell scripts. runit is a very minimal supervision suite used by Void Linux. s6 and the related 66 are micro-init suites favoured by some Artix users. Artix Linux is essentially Arch without systemd, offering OpenRC, runit, s6, dinit, or 66 as choices. Devuan is the same for Debian. For almost everyone in production these are curiosities, but they keep the init landscape from being a monoculture.