Introduction¶

Alpine screenshot

Reverse engineered from the EeePC fastinit
"gaps filled with frog DNA …"
— Claudio Matsuoka

Finit is a process starter and supervisor designed to run as PID 1 on Linux systems. It consists of a set of plugins and can be set up using configuration files. Plugins start at hook points and can run various set up tasks and/or install event handlers that later provide runtime services, e.g., PID file monitoring, or conditions.

Features¶

Runlevels, defined per service
One-shot tasks, services (daemons), or SysV init start/stop scripts
Runparts and /etc/rc.local support
Process supervision similar to systemd
Sourcing environment files
Conditions for network/process/custom dependencies
Readiness notification; PID files (native) for synchronizing system startup, support for systemd sd_notify(), or s6 style too
Limited support for tmpfiles.d(5) (no aging, attributes, or subvolumes)
Pre/Post script actions
Rudimentary templating support
Tooling to enable/disable services
Built-in getty
Built-in watchdog, with support for hand-over to watchdogd
Built-in support for Debian/BusyBox /etc/network/interfaces
Cgroups v2, both configuration and monitoring in initctl top
Plugin support for customization
Proper rescue mode with bundled sulogin for protected maintenance shell
Integration with watchdogd for full system supervision
Logging to kernel ring buffer before syslogd has started, see the recommended sysklogd project for complete logging integration and how to log to the kernel ring buffer from scripts using logger

For a more thorough overview, see the Features section.

Tip

See SysV Init Compatibility for help to quickly get going with an existing SysV or BusyBox init setup.

Origin¶

This project is based on the original finit by Claudio Matsuoka which was reverse engineered from syscalls of the EeePC fastinit.

Finit is developed and maintained by Joachim Wiberg at GitHub. Please file bug reports, clone it, or send pull requests for bug fixes and proposed extensions.