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RC(8)			FreeBSD	System Manager's Manual			 RC(8)

NAME
     rc	-- command scripts for auto-reboot and daemon startup

SYNOPSIS
     rc
     rc.conf
     rc.conf.local
     rc.d/
     rc.firewall
     rc.local
     rc.resume
     rc.shutdown
     rc.subr

DESCRIPTION
     The rc utility is the command script which	controls the automatic boot
     process after being called	by init(8).  The rc.local script contains com-
     mands which are pertinent only to a specific site.	 Typically, the
     /usr/local/etc/rc.d/ mechanism is used instead of rc.local	these days but
     if	you want to use	rc.local, it is	still supported.  In this case,	it
     should source /etc/rc.conf	and contain additional custom startup code for
     your system.  The best way	to handle rc.local, however, is	to separate it
     out into rc.d/ style scripts and place them under /usr/local/etc/rc.d/.
     The rc.conf file contains the global system configuration information
     referenced	by the startup scripts,	while rc.conf.local contains the local
     system configuration.  See	rc.conf(5) for more information.

     The rc.d/ directories contain scripts which will be automatically exe-
     cuted at boot time	and shutdown time.

     The service(8) command provides a convenient interface to manage rc.d
     services.

     The sysrc(8) command provides a scripting interface to modify system con-
     fig files.

   Operation of	rc
     1.	  If autobooting, set autoboot=yes and enable a	flag (rc_fast=yes),
	  which	prevents the rc.d/ scripts from	performing the check for al-
	  ready	running	processes (thus	speeding up the	boot process).	This
	  rc_fast=yes speedup will not occur when rc is	started	up after exit-
	  ing the single-user shell.

     2.	  Determine whether the	system is booting diskless, and	if so run the
	  /etc/rc.initdiskless script.

     3.	  Source /etc/rc.subr to load various rc.subr(8) shell functions to
	  use.

     4.	  Load the configuration files.

     5.	  Determine if booting in a jail, and add "nojail" (no jails allowed)
	  or "nojailvnet" (only	allow vnet-enabled jails) to the list of KEY-
	  WORDS	to skip	in rcorder(8).

     6.	  If the file ${firstboot_sentinel} does not exist, add	"firstboot" to
	  the list of KEYWORDS to skip in rcorder(8).

     7.	  Invoke rcorder(8) to order the files in /etc/rc.d/ that do not have
	  a "nostart" KEYWORD (refer to	rcorder(8)'s -s	flag).

     8.	  Call each script in turn using run_rc_script() (from rc.subr(8)),
	  which	sets $1	to "start", and	sources	the script in a	subshell.
	  Stop processing when the script that is the value of the
	  $early_late_divider has been run.

     9.	  Check	again to see if	the file ${firstboot_sentinel} exists (in case
	  it is	located	on a newly mounted file	system)	and adjust the list of
	  KEYWORDs to skip appropriately.

     10.  Re-run rcorder(8), this time including the scripts in	the
	  $local_startup directories.  Ignore everything up to the
	  $early_late_divider, then start executing the	scripts	as described
	  above.

     11.  If the file ${firstboot_sentinel} exists, delete it.	If the file
	  ${firstboot_sentinel}-reboot also exists (because it was created by
	  a script), then delete it and	reboot.

   Operation of	rc.shutdown
     1.	  Set rc_shutdown to the value of the first argument passed to
	  rc.shutdown or to "unspecified" if no	argument was passed.

     2.	  Source /etc/rc.subr to load various rc.subr(8) shell functions to
	  use.

     3.	  Load the configuration files.

     4.	  Invoke rcorder(8) to order the files in /etc/rc.d/ and the
	  $local_startup directories that have a "shutdown" KEYWORD (refer to
	  rcorder(8)'s -k flag), reverse that order, and assign	the result to
	  a variable.

     5.	  Call each script in turn using run_rc_script() (from rc.subr(8)),
	  which	sets $1	to "faststop", and sources the script in a subshell.

   Contents of rc.d/
     rc.d/ is located in /etc/rc.d/.  The following file naming	conventions
     are currently used	in rc.d/:

	   ALLUPPERCASE	 Scripts that are "placeholders" to ensure that	cer-
			 tain operations are performed before others.  In or-
			 der of	startup, these are:

			 FILESYSTEMS  Ensure that root and other critical file
				      systems are mounted.  This is the	de-
				      fault $early_late_divider.

			 NETWORKING   Ensure basic network services are	run-
				      ning, including general network configu-
				      ration.

			 SERVERS      Ensure basic services exist for services
				      that start early (such as	nisdomain),
				      because they are required	by DAEMON be-
				      low.

			 DAEMON	      Check-point before all general purpose
				      daemons such as lpd and ntpd.

			 LOGIN	      Check-point before user login services
				      (inetd and sshd),	as well	as services
				      which might run commands as users	(cron
				      and sendmail).

	   bar		 Scripts that are sourced in a subshell.  The boot
			 does not stop if such a script	terminates with	a non-
			 zero status, but a script can stop the	boot if	neces-
			 sary by invoking the stop_boot() function (from
			 rc.subr(8)).

     Each script should	contain	rcorder(8) keywords, especially	an appropriate
     "PROVIDE" entry, and if necessary "REQUIRE" and "BEFORE" keywords.

     Each script is expected to	support	at least the following arguments,
     which are automatically supported if it uses the run_rc_command() func-
     tion:

	   start    Start the service.	This should check that the service is
		    to be started as specified by rc.conf(5).  Also checks if
		    the	service	is already running and refuses to start	if it
		    is.	 This latter check is not performed by standard
		    FreeBSD scripts if the system is starting directly to
		    multi-user mode, to	speed up the boot process.  If
		    forcestart is given, ignore	the rc.conf(5) check and start
		    anyway.

	   stop	    If the service is to be started as specified by
		    rc.conf(5),	stop the service.  This	should check that the
		    service is running and complain if it is not.  If
		    forcestop is given,	ignore the rc.conf(5) check and	at-
		    tempt to stop.

	   restart  Perform a stop then	a start.

	   status   If the script starts a process (rather than	performing a
		    one-off operation),	show the status	of the process.	 Oth-
		    erwise it is not necessary to support this argument.  De-
		    faults to displaying the process ID	of the program (if
		    running).

	   enable   Enable the service in rc.conf(5).

	   disable  Disable the	service	in rc.conf(5).

	   delete   Remove the service from rc.conf(5).	 If
		    `service_delete_empty' is set to "YES",
		    /etc/rc.conf.d/$servicename	will be	deleted	if empty after
		    modification.

	   describe
		    Print a short description of what the script does.

	   extracommands
		    Print the script's non-standard commands.

	   poll	    If the script starts a process (rather than	performing a
		    one-off operation),	wait for the command to	exit.  Other-
		    wise it is not necessary to	support	this argument.

	   enabled  Return 0 if	the service is enabled and 1 if	it is not.
		    This command does not print	anything.

	   rcvar    Display which rc.conf(5) variables are used	to control the
		    startup of the service (if any).

     If	a script must implement	additional commands it can list	them in	the
     extra_commands variable, and define their actions in a variable construc-
     ted from the command name (see the	EXAMPLES section).

     The following key points apply to old-style scripts in
     /usr/local/etc/rc.d/:

     o	 Scripts are only executed if their basename(1)	matches	the shell
	 globbing pattern *.sh,	and they are executable.  Any other files or
	 directories present within the	directory are silently ignored.

     o	 When a	script is executed at boot time, it is passed the string
	 "start" as its	first and only argument.  At shutdown time, it is
	 passed	the string "stop" as its first and only	argument.  All rc.d/
	 scripts are expected to handle	these arguments	appropriately.	If no
	 action	needs to be taken at a given time (either boot time or shut-
	 down time), the script	should exit successfully and without producing
	 an error message.

     o	 The scripts within each directory are executed	in lexicographical or-
	 der.  If a specific order is required,	numbers	may be used as a pre-
	 fix to	the existing filenames,	so for example 100.foo would be	exe-
	 cuted before 200.bar; without the numeric prefixes the	opposite would
	 be true.

     o	 The output from each script is	traditionally a	space character, fol-
	 lowed by the name of the software package being started or shut down,
	 without a trailing newline character.

SCRIPTS	OF INTEREST
     When an automatic reboot is in progress, rc is invoked with the argument
     autoboot.	One of the scripts run from /etc/rc.d/ is /etc/rc.d/fsck.
     This script runs fsck(8) with option -p and -F to "preen" all the disks
     of	minor inconsistencies resulting	from the last system shutdown.	If
     this fails, then checks/repairs of	serious	inconsistencies	caused by
     hardware or software failure will be performed in the background at the
     end of the	booting	process.  If autoboot is not set, when going from sin-
     gle-user to multi-user mode for example, the script does not do anything.

     The /etc/rc.d/local script	can execute scripts from multiple rc.d/	direc-
     tories.  The default location includes /usr/local/etc/rc.d/, but these
     may be overridden with the	local_startup rc.conf(5) variable.

     The /etc/rc.d/serial script is used to set	any special configurations for
     serial devices.

     The rc.firewall script is used to configure rules for the kernel based
     firewall service.	It has several possible	options:

	   open	     will allow	anyone in
	   client    will try to protect just this machine
	   simple    will try to protect a whole network
	   closed    totally disables IP services except via lo0 interface
	   UNKNOWN   disables the loading of firewall rules
	   filename  will load the rules in the	given filename (full path re-
		     quired).

     Most daemons, including network related daemons, have their own script in
     /etc/rc.d/, which can be used to start, stop, and check the status	of the
     service.

     Any architecture specific scripts,	such as	/etc/rc.d/apm for example,
     specifically check	that they are on that architecture before starting the
     daemon.

     Following tradition, all startup files reside in /etc.

FILES
     /etc/rc
     /etc/rc.conf
     /etc/rc.conf.local
     /etc/rc.d/
     /etc/rc.firewall
     /etc/rc.local
     /etc/rc.shutdown
     /etc/rc.subr
     /var/run/dmesg.boot	       dmesg(8)	results	soon after the rc
				       process begins.	Useful when dmesg(8)
				       buffer in the kernel no longer has this
				       information.

EXAMPLES
     The following is a	minimal	rc.d/ style script.  Most scripts require lit-
     tle more than the following.

	   #!/bin/sh
	   #

	   # PROVIDE: foo
	   # REQUIRE: bar_service_required_to_precede_foo

	   . /etc/rc.subr

	   name="foo"
	   rcvar=foo_enable
	   command="/usr/local/bin/foo"

	   load_rc_config $name
	   run_rc_command "$1"

     Certain scripts may want to provide enhanced functionality.  The user may
     access this functionality through additional commands.  The script	may
     list and define as	many commands at it needs.

	   #!/bin/sh
	   #

	   # PROVIDE: foo
	   # REQUIRE: bar_service_required_to_precede_foo
	   # BEFORE:  baz_service_requiring_foo_to_precede_it

	   . /etc/rc.subr

	   name="foo"
	   rcvar=foo_enable
	   command="/usr/local/bin/foo"
	   extra_commands="nop hello"
	   hello_cmd="echo Hello World."
	   nop_cmd="do_nop"

	   do_nop()
	   {
		   echo	"I do nothing."
	   }

	   load_rc_config $name
	   run_rc_command "$1"

     As	all processes are killed by init(8) at shutdown, the explicit kill(1)
     is	unnecessary, but is often included.

SEE ALSO
     kill(1), rc.conf(5), init(8), rc.resume(8), rc.subr(8), rcorder(8),
     reboot(8),	savecore(8), service(8), sysrc(8)

     Practical rc.d scripting in BSD, https://docs.freebsd.org/en/articles/rc-
     scripting/.

HISTORY
     The rc utility appeared in	4.0BSD.

FreeBSD	13.0			 July 4, 2022			  FreeBSD 13.0

NAME | SYNOPSIS | DESCRIPTION | SCRIPTS OF INTEREST | FILES | EXAMPLES | SEE ALSO | HISTORY

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