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 au

tomatic boot
process after being called by init(8). The rc.local script

contains commands which are pertinent only to a specific site. Typical

ly, 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 con

tains the local
system configuration. See rc.conf(5) for more information.

The rc.d/ directories contain scripts which will be automat

ically 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
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 di

rectly 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
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 as

sign 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 thatcertain operations are performed be

fore others.
In order of startup, these are:

NETWORKING Ensure basic network

services are
running, including

general network configuration.

SERVERS Ensure basic ser

vices 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).

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 sub

shell. These
can stop the boot if necessary with

the following
shell commands:

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

fi
exit 1

Note that this should be used ex

tremely sparingly!

Each script should contain rcorder(8) keywords, especially

an appropriate
``PROVIDE'' entry, and if necessary ``REQUIRE'' and ``BE

FORE'' 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 speci

fied 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.
Otherwise 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 performinga one-off operation), wait for the com

mand 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 vari

able constructed 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 argu

ment. All rc.d/
scripts are expected to handle these arguments appropri

ately. 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.

+o The scripts within each directory are executed in lexi

cographical
order. 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 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 (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 software failure will be performed in the back

ground 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 rc.early script is run very early in the startup pro

cess, immediately
before the file system check. The rc.early script is depre

cated. 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/ directories. 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 con

figurations 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 file

name (full path
required).

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 com

pletes the
interface configuration and defines PVCs and permanent AT

MARP 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 af

ter the rc pro
cess 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 ex

plicit kill(1)
is unnecessary, but is often included.

SEE ALSO

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

boot(8),
savecore(8)

HISTORY

The rc utility appeared in 4.0BSD.

BSD December 19, 2005

BSD