Skip to content

Configuration Example

This example /etc/finit.conf can also be split up in multiple .conf files in /etc/finit.d. Available, but not yet enabled, services can be placed in /etc/finit.d/available and enabled by an operator using the initctl tool.

See the contrib/ directory on GitHub for examples, or take a peek at systems using Finit, like Infix OS and myLinux.

Tip

As of Finit v4.4, .conf lines can be broken up using the standard UNIX continuation character (\), trailing comments are also supported. The latter means you must escape any hashes used in directives and descriptions (\#). For more on this and examples, see the finit.conf(5) manual or the Configuration section.

# Fallback if /etc/hostname is missing
host default

# Runlevel to start after bootstrap, 'S', default: 2
#runlevel 2

# Support for setting global environment variables, using foo=bar syntax
# be careful though with variables like PATH, SHELL, LOGNAME, etc.
#PATH=/usr/bin:/bin:/usr/sbin:/sbin

# Max file size for each log file: 100 kiB, rotate max 4 copies:
# log => log.1 => log.2.gz => log.3.gz => log.4.gz
log size=100k count=4

# Services to be monitored and respawned as needed
service [S12345] env:-/etc/conf.d/watchdog watchdog $WATCHDOG_OPTS $WATCHDOG_DEV -- System watchdog daemon
service [S12345] env:-/etc/conf.d/syslog syslogd -n $SYSLOGD_OPTS          -- System log daemon
service [S12345] <pid/syslogd> env:-/etc/conf.d/klogd klogd -n $KLOGD_OPTS -- Kernel log daemon
service   [2345] env:-/etc/conf.d/lldpd lldpd -d $LLDPD_OPTS               -- LLDP daemon (IEEE 802.1ab)

# The BusyBox ntpd does not use syslog when running in the foreground
# So we use this trick to redirect stdout/stderr to a log file.  The
# log file is rotated with the above settings.  The condition declares
# a dependency on a system default route (gateway) to be set.  A single
# <!> at the beginning means ntpd does not respect SIGHUP for restart.
service [2345] log:/var/log/ntpd.log <!net/route/default> ntpd -n -l -I eth0 -- NTP daemon

# For multiple instances of the same service, add :ID somewhere between
# the service/run/task keyword and the command.
service :80   [2345] merecat -n -p 80   /var/www -- Web server
service :8080 [2345] merecat -n -p 8080 /var/www -- Old web server

# Alternative method instead of below runparts, can also use /etc/rc.local
#sysv [S] /etc/init.d/keyboard-setup       -- Setting up preliminary keymap
#sysv [S] /etc/init.d/acpid                -- Starting ACPI Daemon
#task [S] /etc/init.d/kbd                  -- Preparing console

# Hidden from boot progress, using empty `--` description
#sysv [S] /etc/init.d/keyboard-setup       --
#sysv [S] /etc/init.d/acpid                --
#task [S] /etc/init.d/kbd                  --

# Run start scripts from this directory
# runparts /etc/start.d

# Virtual consoles run BusyBox getty, keep kernel default speed
tty [12345] /sbin/getty -L 0 /dev/tty1  linux nowait noclear
tty [2345]  /sbin/getty -L 0 /dev/tty2  linux nowait noclear
tty [2345]  /sbin/getty -L 0 /dev/tty3  linux nowait noclear

# Use built-in getty for serial port and USB serial
#tty [12345] /dev/ttyAMA0 noclear nowait
#tty [12345] /dev/ttyUSB0 noclear

# Just give me a shell, I need to debug this embedded system!
#tty [12345] console noclear nologin

The service stanza, as well as task, run and others are described in full in the Services Syntax section.

Here's a quick overview of some of the most common components needed to start a UNIX daemon:

service [LVLS] <COND> log env:[-]/etc/default/daemon daemon ARGS -- Example daemon
^       ^      ^      ^   ^                          ^      ^       ^
|       |      |      |   |                          |      |        `---------- Optional description
|       |      |      |   |                          |       `------------------ Daemon arguments
|       |      |      |   |                           `------------------------- Path to daemon
|       |      |      |    `---------------------------------------------------- Optional env. file
|       |      |       `-------------------------------------------------------- Redirect output to log
|       |       `--------------------------------------------------------------- Optional conditions
|        `---------------------------------------------------------------------- Optional Runlevels
 `------------------------------------------------------------------------------ Supervised program (daemon)

Some components are optional: runlevel(s), condition(s) and description, making it easy to create simple start scripts and still possible for more advanced uses as well:

service /usr/sbin/sshd -D

Dependencies are handled using conditions. One of the most common conditions is to wait for basic networking to become available:

service <net/route/default> nginx -- High performance HTTP server

Here is another example where we instruct Finit to not start BusyBox ntpd until syslogd has started properly. Finit waits for syslogd to create its PID file, by default /var/run/syslogd.pid.

service [2345] log <!pid/syslogd> ntpd -n -N -p pool.ntp.org
service [S12345] syslogd -n -- Syslog daemon

Notice the log keyword, BusyBox ntpd uses stderr for logging when run in the foreground. With log Finit redirects stdout + stderr to the system log daemon using the command line logger(1) tool.

A service, or task, can have multiple dependencies listed. Here we wait for both syslogd to have started and basic networking to be up:

service [2345] log <pid/syslogd,net/route/default> ntpd -n -N -p pool.ntp.org

If either condition fails, e.g. loss of networking, ntpd is stopped and as soon as it comes back up again ntpd is restarted automatically.

Note

Make sure daemons do not fork and detach themselves from the controlling TTY, usually an -n or -f flag, or -D as in the case of OpenSSH above. If it detaches itself, Finit cannot monitor it and will instead try to restart it.