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

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


     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.

   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 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

     4.   Load the configuration files.

     5.   Determine if booting in a jail, and add ``nojail'' to the list of
          KEYWORDS 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
          current 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

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

     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 cer-
                         tain operations are performed before others.  In
                         order of startup, these are:

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

                         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
                                     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).

         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.  These can
                         stop the boot if necessary with the following shell

                               if [ "$autoboot" = yes ]; then
                                       kill -TERM $$
                               exit 1

                         Note that this should be used extremely sparingly!

     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-

           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

           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.  Oth-
                    erwise it is not necessary to support this argument.
                    Defaults to displaying the process ID of the program (if

           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.

           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 con-
     structed from the command name (see the EXAMPLES section).

     The following key points apply to old-style scripts in

     +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
         order.  If a specific order is required, numbers may be used as a
         prefix to the existing filenames, so for example would be
         executed before; 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 (see the EXAMPLES section).

     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 rc.early script is run very early in the startup process, immediately
     before the file system check.  The rc.early script is deprecated.  Any
     commands in this file should be separated out into rc.d/ style scripts
     and integrated into the rc system.

     The /etc/rc.d/local script can execute scripts from multiple rc.d/ direc-
     tories.  The default locations are /usr/local/etc/rc.d/ and
     /usr/X11R6/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

     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

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

     Following tradition, all startup files reside in /etc.

     /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

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


           # PROVIDE: foo
           # REQUIRE: bar_service_required_to_precede_foo

           . /etc/rc.subr


           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.


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

           . /etc/rc.subr

           extra_commands="nop hello"
           hello_cmd="echo Hello World."

                   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.

     kill(1), rc.conf(5), init(8), rcorder(8), rc.subr(8), reboot(8),

     The rc utility appeared in 4.0BSD.

FreeBSD 6.2                    December 19, 2005                   FreeBSD 6.2


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