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RC(8)			     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.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 ref-
     erenced by the startup scripts, while rc.conf.local contains the local sys-
     tem configuration.  See rc.conf(5) for more information.

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

   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 already
	  running  processes  (thus  speeding  up  the	boot   process).    This
	  rc_fast=yes speedup will not occur when rc is started up after exiting
	  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" to the list	of  KEY-
	  WORDS to skip in rcorder(8).

     6.   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).

     7.   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.  If
	  the script has a .sh suffix then it is sourced directly into the  cur-
	  rent	shell.	Stop processing when the script that is the value of the
	  $early_late_divider has been run.

     8.   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.

   Operation of rc.shutdown
     1.   Source /etc/rc.subr to load various rc.subr(8) shell functions to use.

     2.   Load the configuration files.

     3.   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.

     4.   Call each script in  turn  using  run_rc_script()  (from  rc.subr(8)),
	  which sets $1 to "stop", and sources the script in a subshell.  If the
	  script  has  a .sh suffix then it is sourced directly into the current
	  shell.

   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 certain
			 operations are performed before others.   In  order  of
			 startup, these are:

			 NETWORKING  Ensure  basic network services are running,
				     including general network configuration.

			 SERVERS     Ensure basic services  exist  for	services
				     that  start  early (such as named), because
				     they are required by DAEMON below.

			 DAEMON      Check-point before all general purpose dae-
				     mons 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).

	   foo.sh	 Scripts that are to be sourced into the  current  shell
			 rather than a subshell have a .sh suffix.  Extreme care
			 must  be  taken  in using this, as the startup sequence
			 will terminate if the script does.

	   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 necessary  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() function:

	   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 attempt 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.  Other-
		    wise it is not necessary to support this argument.	Defaults
		    to displaying the process ID of the program (if running).

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

	   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 constructed
     from the command name (see the "EXAMPLES" section).

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

     *	 Scripts are only executed if their basename(1) matches the shell  glob-
	 bing  pattern *.sh, and they are executable.  Any other files or direc-
	 tories present within the directory are silently ignored.

     *	 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 shutdown time), the
	 script should exit successfully and without producing an error message.

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

     *	 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 (see the "EXAMPLES" section).

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 soft-
     ware failure will be performed in the background at the end of the  booting
     process.  If autoboot is not set, when going from single-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/ directo-
     ries.  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).

     The /etc/rc.d/atm* scripts are used to configure  ATM  network  interfaces.
     The interfaces are configured in three passes.  The first pass performs the
     initial  interface  configuration.  The second pass completes the interface
     configuration and defines PVCs and permanent  ATMARP  entries.   The  third
     pass starts any ATM daemons.

     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 little
     more than the following.

	   #!/bin/sh
	   #

	   # PROVIDE: foo
	   # REQUIRE: bar_service_required_to_precede_foo

	   . /etc/rc.subr

	   name="foo"
	   rcvar=`set_rcvar`
	   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=`set_rcvar`
	   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),   rcorder(8),	rc.subr(8),   reboot(8),
     savecore(8)

HISTORY
     The rc utility appeared in 4.0BSD.

FreeBSD 9.1			November 17, 2009			   RC(8)

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