How to install runit
Upgrading from previous versions of runit
Benefits
How to replace init
How to use runit with current init
How to experiment with runit and other init
schemes
Frequently asked questions
Runlevels
Service dependencies
A collection of run scripts
The runit program
The runit-init program
The runsvdir program
The runsvchdir
program
The runsv program
runit is a cross-platform Unix init scheme with service supervision, a replacement for sysvinit and other init schemes. It runs on GNU/Linux, *BSD, MacOSX, Solaris, and can easily be adapted to other Unix operating systems. If runit runs for you on any other operating system, please let me know.
Contribute to runit through GitHub runit.
runit is discussed on the <supervision@list.skarnet.org> mailing list. Please contact this list and not me privately.
To subscribe send an empty email to <supervision-subscribe@list.skarnet.org>.
Mailing list archives are available at skarnet.org, and mail-archive.com.
The program runit is intended to run as
Unix process no 1, it is automatically started by the runit-init
/sbin/init-replacement if this is started by the
kernel.
runit performs the system's booting, running and shutting down in three stages:
/etc/runit/1 and waits for it to
terminate. The system's one time initialization tasks are done here.
/etc/runit/1 has full control over
/dev/console to be able to start an emergency shell in case
the one time initialization tasks fail./etc/runit/2 which should not return
until the system is going to halt or reboot; if it crashes, it will be
restarted. Normally, /etc/runit/2 runs runsvdir. In Stage 2 runit
optionally handles the INT signal (ctrl-alt-del keyboard request on
Linux/i386)./etc/runit/3. The systems tasks to shutdown and halt or
reboot are done here.These are working examples for Debian sarge: /etc/runit/1, /etc/runit/2, /etc/runit/3.
The program runit-init is intended to
replace /sbin/init. The command
init 0 tells runit to halt the
system, and init 6 to reboot. Runlevels are handled through the runsvdir and runsvchdir programs. Service dependencies are resolved
automatically.
runit is optimized for reliability and small size. The amount of code in process no 1 should be minimal.
See How to install runit for installing runit, and How to replace init for configuring runit to run as process no 1. See How to use with current init if you want to use runit without replacing the current init scheme. Please read the list of Frequently asked questions with answers.
The following distributions are known to include or package runit:
If you know of more distributions, please let me know.
runit in use: I replaced sysvinit successfully with runit on several server systems and a laptop running Debian/GNU Linux sarge, woody, and potato. Here is an example:
# strings /proc/1/exe |grep Id
$Id: runit.c,v 1.7 2002/02/13 09:59:52 pape Exp $
# uptime
11:59:13 up 365 days, 23:22, 3 users, load average: 0.01, 0.02, 0.00
# ps axuw |head -n20
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 0.0 20 16 ? S 2002 0:07 runit
root 2 0.0 0.0 0 0 ? SW 2002 0:00 [keventd]
root 3 0.0 0.0 0 0 ? SWN 2002 0:51 [ksoftirqd_CPU0]
root 4 0.0 0.0 0 0 ? SW 2002 144:38 [kswapd]
root 5 0.0 0.0 0 0 ? SW 2002 0:08 [bdflush]
root 6 0.0 0.0 0 0 ? SW 2002 7:24 [kupdated]
root 168 0.0 0.0 1652 168 ? S 2002 0:27 /usr/sbin/cron
root 174 0.0 0.0 36 24 ? S 2002 1:06 runsvdir /var/service log: ...............................................................................................
root 176 0.0 0.0 20 20 ? S 2002 0:00 runsv qmail-send
root 177 0.0 0.0 20 20 ? S 2002 0:00 runsv getty-5
root 178 0.0 0.0 20 20 ? S 2002 0:00 runsv getty-4
root 179 0.0 0.0 20 20 ? S 2002 0:00 runsv getty-3
root 180 0.0 0.0 20 20 ? S 2002 0:00 runsv getty-2
root 182 0.0 0.0 20 20 ? S 2002 0:00 runsv socklog-unix
root 183 0.0 0.0 1256 4 tty5 S 2002 0:00 /sbin/getty 38400 tty5 linux
root 184 0.0 0.0 1256 4 tty3 S 2002 0:00 getty 38400 tty3 linux
root 185 0.0 0.0 20 20 ? S 2002 0:00 runsv socklog-klog
root 186 0.0 0.0 20 20 ? S 2002 0:00 runsv ssh
root 187 0.0 0.0 1256 4 tty4 S 2002 0:00 getty 38400 tty4 linux
# pstree
runit-+-bdflush
|-cron
|-gcache
|-keventd
|-ksoftirqd_CPU0
|-kswapd
|-kupdated
`-runsvdir-+-runsv-+-multilog
| `-qmail-send-+-qmail-clean
| |-qmail-lspawn
| `-qmail-rspawn---qmail-remote
|-4*[runsv---getty]
|-2*[runsv-+-multilog]
| `-socklog]
|-runsv-+-multilog
| `-sshd-+-sshd---sshd---bash---bash---pstree
| `-sshd---sshd---rsync
|-runsv---clockspeed
|-runsv-+-dnscache
| `-multilog
|-runsv---apache-ssl-+-9*[apache-ssl]
| |-gcache
| `-4*[multilog]
|-7*[runsv-+-multilog]
| `-tcpserver]
|-4*[runsv-+-multilog]
| `-tinydns]
|-runsv---uncat
|-2*[runsv-+-multilog]
| `-tcpsvd]
|-runsv-+-svlogd
| `-tcpsvd-+-smtpfront-qmail
| `-smtpfront-qmail---qmail-queue
`-runsv-+-svlogd
`-tcpsvd---bincimap-up---bincimapdSee https://smarden.org/runit/ for recent information.