Provided by: file-rc_0.8.7_all
runlevel.conf - The file-rc runlevel configuration file
runlevel.conf is the configuration file for the package file-rc an
alternative init(8) boot concept. While the SysV init scheme
implements runlevels through symlinks in /etc/rc?.d/* , file-rc uses
only one file runlevel.conf to replace all these symlinks.
This file consists of 4 columns separated by TABs or spaces with the
- The first column is the sort criteria for starting and stopping the
- The second column consists of a comma-separated list of runlevels in
which the script should be switched ‘off’ or a single ‘-’ if the
script should never be stopped (within that sort-number).
- The third column consists of a comma-separated list of runlevels in
which the script should be switched ‘on’ or a single ‘-’ if the
script should never be started (with that sort-number).
- The last column specifies the full name of the script.
Lines beginning with ‘#’ and empty lines are ignored.
All scripts executed by the init system are located in /etc/init.d.
If a scripts has the .sh suffix it is a bourne shell script and MAY be
handled in an optimized manner. The behaviour of executing script in
an optimized way will not differ in any way from it being forked and
executed in the regular way.
The following runlevels are defined:
N System bootup (NONE).
S Single user mode (not to be switched to directly)
1 single user mode
2..5 multi user mode
When the systems boots, the lines with ’S’ in the third column are
executed. It in turn executes all these scripts in alphabetical (and
thus numerical) order. The first argument passed to the executed
scripts is start. The runlevel at this point is ’N’ (none).
Only things that need to be run once to get the system in a consistent
state are to be run. The ’S’ state is NOT meant to replace rc.local.
One should not start daemons in this runlevel unless absolutely
necessary. Eg, NFS might need the portmapper, so it is OK to start it
early in the bootprocess. But this is not the time to start the squid
After the ’S’ scripts have been executed, init switches to the default
runlevel as specified in /etc/inittab, usually ’2’.
init(8) then executes the /etc/init.d/rc script which takes care of
starting the services with ’2’ in the third column.
Because the previous runlevel is ’N’ (none) the scripts with ’2’ in the
second column will NOT be executed - there is nothing to stop yet, the
system is busy coming up.
If for example there is a service that wants to run in runlevel 4 and
ONLY in that level, it will place ’2,3,5’ in the second column to stop
the service when switching out of runlevel 4. We do not need to run
that script at this point.
The scripts will be executed in alphabetical order, with the first
argument set to ’start’.
When one switches from (for example) runlevel 2 to runlevel 3,
/etc/init.d/rc will first execute in alphabetical order all scripts
with ’3’ in the second column with ’stop’ as first argument and then
all scripts with ’3’ in the third column with ’start’ as first
As an optimization, a check is made for each "service" to see if it was
already running in the previous runlevel. If it was, and there is no
entry present in the second column for the new runlevel, there is no
need to start it a second time so that will not be done.
On the other hand, if there was an entry in the second column, it is
assumed the service was stopped on purpose first and so needs to be
We MIGHT make the same optimization for stop scripts as well - if no
entry in the third column was present in the previous runlevel, we can
assume that service was not running and we don’t need to stop it
either. In that case we can remove the "coming from level N" special
case mentioned above. But right now that has not been implemented.
Single user mode
Switching to single user mode is done by switching to runlevel 1. That
will cause all services to be stopped (assuming they all have ’1’ in
the second column). The runlevel 1 scripts will then switch to runlevel
’S’ which has no scripts - all it does is spawn a shell directly on
/dev/console for maintenance.
Going to runlevel 0 or 6 will cause the system to be halted or
rebooted, respectively. For example, if we go to runlevel 6 (reboot)
first all scripts with ’6’ in the second column will be executed
alphabetically with ’stop’ as the first argument.
Then the scripts with ’6’ in the third column will be executed
alphabetically with ’stop’ as the first argument as well. The reason
is that there is nothing to start anymore at this point - all scripts
that are run are meant to bring the system down.
#<sort> <off> <on> <script>
05 - 0 /etc/init.d/halt
05 - 1 /etc/init.d/single
05 - 6 /etc/init.d/reboot
10 0,1,6 2,3,4,5 /etc/init.d/sysklogd
12 0,1,6 2,3,4,5 /etc/init.d/kerneld
89 0,1,6 2,3,4,5 /etc/init.d/cron
99 - 2,3,4,5 /etc/init.d/rmnologin
99 0,1,6 2,3,4,5 /etc/init.d/xdm
file-rc was originally written by Winfried Trümper <firstname.lastname@example.org>
and adapted to the Debian system by Tom Lees <email@example.com>,
Martin Schulze <firstname.lastname@example.org> and Roland Rosenfeld
This man page was written by Roland Rosenfeld <email@example.com>.