xref: /freebsd/share/man/man8/rc.8 (revision aaa3852435aee8c1b5abfe38ed7d43f9ba57e6dd)
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31.\"     @(#)rc.8	8.2 (Berkeley) 12/11/93
32.\" $FreeBSD$
33.\"
34.Dd September 6, 2019
35.Dt RC 8
36.Os
37.Sh NAME
38.Nm rc
39.Nd command scripts for auto-reboot and daemon startup
40.Sh SYNOPSIS
41.Nm
42.Nm rc.conf
43.Nm rc.conf.local
44.Nm rc.d/
45.Nm rc.firewall
46.Nm rc.local
47.Nm rc.resume
48.Nm rc.shutdown
49.Nm rc.subr
50.Sh DESCRIPTION
51The
52.Nm
53utility is the command script which controls the automatic boot process
54after being called by
55.Xr init 8 .
56The
57.Nm rc.local
58script contains commands which are pertinent only
59to a specific site.
60Typically, the
61.Pa /usr/local/etc/rc.d/
62mechanism is used instead of
63.Nm rc.local
64these days but if
65you want to use
66.Nm rc.local ,
67it is still supported.
68In this case, it should source
69.Pa /etc/rc.conf
70and contain additional custom startup code for your system.
71The best way to handle
72.Nm rc.local ,
73however, is to separate it out into
74.Nm rc.d/
75style scripts and place them under
76.Pa /usr/local/etc/rc.d/ .
77The
78.Nm rc.conf
79file contains the global system configuration information referenced
80by the startup scripts, while
81.Nm rc.conf.local
82contains the local system configuration.
83See
84.Xr rc.conf 5
85for more information.
86.Pp
87The
88.Nm rc.d/
89directories contain scripts which will be automatically
90executed at boot time and shutdown time.
91.Pp
92The
93.Xr service 8
94command provides a convenient interface to manage rc.d services.
95.Pp
96The
97.Xr sysrc 8
98command provides a scripting interface to modify system config files.
99.Ss Operation of Nm
100.Bl -enum
101.It
102If autobooting, set
103.Va autoboot Ns = Ns Li yes
104and enable a flag
105.Pq Va rc_fast Ns = Ns Li yes ,
106which prevents the
107.Nm rc.d/
108scripts from performing the check for already running processes
109(thus speeding up the boot process).
110This
111.Va rc_fast Ns = Ns Li yes
112speedup will not occur when
113.Nm
114is started up after exiting the single-user shell.
115.It
116Determine whether the system is booting diskless,
117and if so run the
118.Pa /etc/rc.initdiskless
119script.
120.It
121Source
122.Pa /etc/rc.subr
123to load various
124.Xr rc.subr 8
125shell functions to use.
126.It
127Load the configuration files.
128.It
129Determine if booting in a jail,
130and add
131.Dq Li nojail
132(no jails allowed) or
133.Dq Li nojailvnet
134(only allow vnet-enabled jails) to the list of KEYWORDS to skip in
135.Xr rcorder 8 .
136.It
137If the file
138.Va ${firstboot_sentinel}
139does not exist, add
140.Dq Li firstboot
141to the list of KEYWORDS to skip in
142.Xr rcorder 8 .
143.It
144Invoke
145.Xr rcorder 8
146to order the files in
147.Pa /etc/rc.d/
148that do not have a
149.Dq Li nostart
150KEYWORD (refer to
151.Xr rcorder 8 Ns 's
152.Fl s
153flag).
154.It
155Call each script in turn using
156.Fn run_rc_script
157(from
158.Xr rc.subr 8 ) ,
159which sets
160.Va $1
161to
162.Dq Li start ,
163and sources the script in a subshell.
164Stop processing when the script that is the value of the
165.Va $early_late_divider
166has been run.
167.It
168Check again to see if the file
169.Va ${firstboot_sentinel}
170exists (in case it is located on a newly mounted file system)
171and adjust the list of KEYWORDs to skip appropriately.
172.It
173Re-run
174.Xr rcorder 8 ,
175this time including the scripts in the
176.Va $local_startup
177directories.
178Ignore everything up to the
179.Va $early_late_divider ,
180then start executing the scripts as described above.
181.It
182If the file
183.Va ${firstboot_sentinel}
184exists, delete it.
185If the file
186.Va ${firstboot_sentinel}-reboot
187also exists (because it was created by a script), then delete it and reboot.
188.El
189.Ss Operation of Nm rc.shutdown
190.Bl -enum
191.It
192Source
193.Pa /etc/rc.subr
194to load various
195.Xr rc.subr 8
196shell functions to use.
197.It
198Load the configuration files.
199.It
200Invoke
201.Xr rcorder 8
202to order the files in
203.Pa /etc/rc.d/
204and the
205.Va $local_startup
206directories
207that have a
208.Dq Li shutdown
209KEYWORD (refer to
210.Xr rcorder 8 Ns 's
211.Fl k
212flag),
213reverse that order, and assign the result to a variable.
214.It
215Call each script in turn using
216.Fn run_rc_script
217(from
218.Xr rc.subr 8 ) ,
219which sets
220.Va $1
221to
222.Dq Li faststop ,
223and sources the script in a subshell.
224.El
225.Ss Contents of Nm rc.d/
226.Nm rc.d/
227is located in
228.Pa /etc/rc.d/ .
229The following file naming conventions are currently used in
230.Nm rc.d/ :
231.Bl -tag -width ".Pa ALLUPPERCASE" -offset indent
232.It Pa ALLUPPERCASE
233Scripts that are
234.Dq placeholders
235to ensure that certain operations are performed before others.
236In order of startup, these are:
237.Bl -tag -width ".Pa NETWORKING"
238.It Pa NETWORKING
239Ensure basic network services are running, including general
240network configuration.
241.It Pa SERVERS
242Ensure basic services
243exist for services that start early (such as
244.Pa nisdomain ) ,
245because they are required by
246.Pa DAEMON
247below.
248.It Pa DAEMON
249Check-point before all general purpose daemons such as
250.Pa lpd
251and
252.Pa ntpd .
253.It Pa LOGIN
254Check-point before user login services
255.Pa ( inetd
256and
257.Pa sshd ) ,
258as well as services which might run commands as users
259.Pa ( cron
260and
261.Pa sendmail ) .
262.El
263.It Pa bar
264Scripts that are sourced in a subshell.
265The boot does not stop if such a script terminates with a non-zero status,
266but a script can stop the boot if necessary by invoking the
267.Fn stop_boot
268function (from
269.Xr rc.subr 8 ) .
270.El
271.Pp
272Each script should contain
273.Xr rcorder 8
274keywords, especially an appropriate
275.Dq Li PROVIDE
276entry, and if necessary
277.Dq Li REQUIRE
278and
279.Dq Li BEFORE
280keywords.
281.Pp
282Each script is expected to support at least the following arguments, which
283are automatically supported if it uses the
284.Fn run_rc_command
285function:
286.Bl -tag -width ".Cm restart" -offset indent
287.It Cm start
288Start the service.
289This should check that the service is to be started as specified by
290.Xr rc.conf 5 .
291Also checks if the service is already running and refuses to start if
292it is.
293This latter check is not performed by standard
294.Fx
295scripts if the system is starting directly to multi-user mode, to
296speed up the boot process.
297If
298.Cm forcestart
299is given, ignore the
300.Xr rc.conf 5
301check and start anyway.
302.It Cm stop
303If the service is to be started as specified by
304.Xr rc.conf 5 ,
305stop the service.
306This should check that the service is running and complain if it is not.
307If
308.Cm forcestop
309is given, ignore the
310.Xr rc.conf 5
311check and attempt to stop.
312.It Cm restart
313Perform a
314.Cm stop
315then a
316.Cm start .
317.It Cm status
318If the script starts a process (rather than performing a one-off
319operation), show the status of the process.
320Otherwise it is not necessary to support this argument.
321Defaults to displaying the process ID of the program (if running).
322.It Cm enable
323Enable the service in
324.Xr rc.conf 5 .
325.It Cm disable
326Disable the service in
327.Xr rc.conf 5 .
328.It Cm delete
329Remove the service from
330.Xr rc.conf 5 .
331If
332.Ql Li service_delete_empty
333is set to
334.Dq Li YES ,
335.Pa /etc/rc.conf.d/$servicename
336will be deleted if empty after modification.
337.It Cm describe
338Print a short description of what the script does.
339.It Cm extracommands
340Print the script's non-standard commands.
341.It Cm poll
342If the script starts a process (rather than performing a one-off
343operation), wait for the command to exit.
344Otherwise it is not necessary to support this argument.
345.It Cm enabled
346Return 0 if the service is enabled and 1 if it is not.
347This command does not print anything.
348.It Cm rcvar
349Display which
350.Xr rc.conf 5
351variables are used to control the startup of the service (if any).
352.El
353.Pp
354If a script must implement additional commands it can list them in
355the
356.Va extra_commands
357variable, and define their actions in a variable constructed from
358the command name (see the
359.Sx EXAMPLES
360section).
361.Pp
362The following key points apply to old-style scripts in
363.Pa /usr/local/etc/rc.d/ :
364.Bl -bullet
365.It
366Scripts are only executed if their
367.Xr basename 1
368matches the shell globbing pattern
369.Pa *.sh ,
370and they are executable.
371Any other files or directories present within the directory are silently
372ignored.
373.It
374When a script is executed at boot time, it is passed the string
375.Dq Li start
376as its first and only argument.
377At shutdown time, it is passed the string
378.Dq Li stop
379as its first and only argument.
380All
381.Nm rc.d/
382scripts are expected to handle these arguments appropriately.
383If no action needs to be taken at a given time
384(either boot time or shutdown time),
385the script should exit successfully and without producing an error message.
386.It
387The scripts within each directory are executed in lexicographical order.
388If a specific order is required,
389numbers may be used as a prefix to the existing filenames,
390so for example
391.Pa 100.foo
392would be executed before
393.Pa 200.bar ;
394without the numeric prefixes the opposite would be true.
395.It
396The output from each script is traditionally a space character,
397followed by the name of the software package being started or shut down,
398.Em without
399a trailing newline character.
400.El
401.Sh SCRIPTS OF INTEREST
402When an automatic reboot is in progress,
403.Nm
404is invoked with the argument
405.Cm autoboot .
406One of the scripts run from
407.Pa /etc/rc.d/
408is
409.Pa /etc/rc.d/fsck .
410This script runs
411.Xr fsck 8
412with option
413.Fl p
414and
415.Fl F
416to
417.Dq preen
418all the disks of minor inconsistencies resulting
419from the last system shutdown.
420If this fails, then checks/repairs of serious inconsistencies
421caused by hardware or software failure will be performed
422in the background at the end of the booting process.
423If
424.Cm autoboot
425is not set, when going from single-user to multi-user mode for example,
426the script does not do anything.
427.Pp
428The
429.Pa /etc/rc.d/local
430script can execute scripts from multiple
431.Nm rc.d/
432directories.
433The default location includes
434.Pa /usr/local/etc/rc.d/ ,
435but these may be overridden with the
436.Va local_startup
437.Xr rc.conf 5
438variable.
439.Pp
440The
441.Pa /etc/rc.d/serial
442script is used to set any special configurations for serial devices.
443.Pp
444The
445.Nm rc.firewall
446script is used to configure rules for the kernel based firewall
447service.
448It has several possible options:
449.Pp
450.Bl -tag -width ".Ar filename" -compact -offset indent
451.It Cm open
452will allow anyone in
453.It Cm client
454will try to protect just this machine
455.It Cm simple
456will try to protect a whole network
457.It Cm closed
458totally disables IP services except via
459.Pa lo0
460interface
461.It Cm UNKNOWN
462disables the loading of firewall rules
463.It Ar filename
464will load the rules in the given filename (full path required).
465.El
466.Pp
467Most daemons, including network related daemons, have their own script in
468.Pa /etc/rc.d/ ,
469which can be used to start, stop, and check the status of the service.
470.Pp
471Any architecture specific scripts, such as
472.Pa /etc/rc.d/apm
473for example, specifically check that they are on that architecture
474before starting the daemon.
475.Pp
476Following tradition, all startup files reside in
477.Pa /etc .
478.Sh FILES
479.Bl -tag -compact -width Pa
480.It Pa /etc/rc
481.It Pa /etc/rc.conf
482.It Pa /etc/rc.conf.local
483.It Pa /etc/rc.d/
484.It Pa /etc/rc.firewall
485.It Pa /etc/rc.local
486.It Pa /etc/rc.shutdown
487.It Pa /etc/rc.subr
488.It Pa /var/run/dmesg.boot
489.Xr dmesg 8
490results soon after the
491.Nm
492process begins.
493Useful when
494.Xr dmesg 8
495buffer in the kernel no longer has this information.
496.El
497.Sh EXAMPLES
498The following is a minimal
499.Nm rc.d/
500style script.
501Most scripts require little more than the following.
502.Bd -literal -offset indent
503#!/bin/sh
504#
505
506# PROVIDE: foo
507# REQUIRE: bar_service_required_to_precede_foo
508
509\&. /etc/rc.subr
510
511name="foo"
512rcvar=foo_enable
513command="/usr/local/bin/foo"
514
515load_rc_config $name
516run_rc_command "$1"
517.Ed
518.Pp
519Certain scripts may want to provide enhanced functionality.
520The user may access this functionality through additional commands.
521The script may list and define as many commands at it needs.
522.Bd -literal -offset indent
523#!/bin/sh
524#
525
526# PROVIDE: foo
527# REQUIRE: bar_service_required_to_precede_foo
528# BEFORE:  baz_service_requiring_foo_to_precede_it
529
530\&. /etc/rc.subr
531
532name="foo"
533rcvar=foo_enable
534command="/usr/local/bin/foo"
535extra_commands="nop hello"
536hello_cmd="echo Hello World."
537nop_cmd="do_nop"
538
539do_nop()
540{
541	echo "I do nothing."
542}
543
544load_rc_config $name
545run_rc_command "$1"
546.Ed
547.Pp
548As all processes are killed by
549.Xr init 8
550at shutdown, the explicit
551.Xr kill 1
552is unnecessary, but is often included.
553.Sh SEE ALSO
554.Xr kill 1 ,
555.Xr rc.conf 5 ,
556.Xr init 8 ,
557.Xr rc.resume 8 ,
558.Xr rc.subr 8 ,
559.Xr rcorder 8 ,
560.Xr reboot 8 ,
561.Xr savecore 8 ,
562.Xr service 8 ,
563.Xr sysrc 8
564.Sh HISTORY
565The
566.Nm
567utility appeared in
568.Bx 4.0 .
569