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


     rc - command scripts for system startup




     rc is the command script that is invoked by init(8) when the system
     starts up.  It performs system housekeeping chores and starts up system
     daemons.  Additionally, rc is intricately tied to the netstart(8) script,
     which runs commands and daemons pertaining to the network.  rc is also
     used to execute any rc.d(8) scripts defined in rc.conf.local(8).  The
     rc.securelevel, rc.firsttime, and rc.local scripts hold commands which
     are pertinent only to a specific site.

     All of these startup scripts are controlled to some extent by variables
     defined in rc.conf(8), which specify which daemons and services to run.

     Before init(8) starts rc, it sets the process priority, umask, and
     resource limits according to the ``daemon'' login class as described in
     login.conf(5).  It then starts rc and attempts to execute the sequence of
     commands therein.

     The first part of rc runs an fsck(8) with option -p to ``preen'' all
     disks of minor inconsistencies resulting from the last system shutdown
     and to check for serious inconsistencies caused by hardware or software
     failure.  If this auto-check and repair succeeds, then the second part of
     rc is run.  However, if the file /fastboot exists, fsck will not be
     invoked.  The file is then removed so that fsck will be run on subsequent

     The second part of rc then asks rc.conf(8) for configuration variables,
     mounts filesystems, saves dmesg(8) output to the file
     /var/run/dmesg.boot, starts system daemons, preserves editor files,
     clears the scratch directory /tmp, and saves any possible core image that
     might have been generated as a result of a system crash, with

     If at any point the boot script fails, init(8) enters single-user mode,
     allowing the superuser a shell on the console.  On exiting this mode,
     init again invokes rc, but this time without performing the file system

     Before rc starts most system daemons, netstart(8) is executed.

     rc.securelevel is executed by rc to start daemons that must be run before
     the security level changes.  Following this, rc then sets the security
     level to '1' if it wasn't set already by rc.securelevel.  See
     securelevel(7) for the effects of setting the security level.

     If rc.firsttime exists, it is executed once and then deleted.  Any output
     is mailed to root.

     rc.local is executed towards the end of rc (it is not the very last as
     there are a few services that must be started at the very end).
     Normally, rc.local contains commands and daemons that are not part of the
     stock installation.


     /etc/netstart          Command script for network startup.
     /etc/rc                Command scripts for system startup.
     /etc/rc.conf           System daemon configuration database.
     /etc/rc.conf.local     Site specific daemon configuration database.
     /etc/rc.d              Directory to hold rc.d(8) scripts.
     /etc/rc.d/rc.subr      Functions used by the rc.d(8) scripts.
     /etc/rc.firsttime      Commands run on the first boot after creation.
     /etc/rc.local          Site specific command scripts for system startup.
     /etc/rc.securelevel    Commands run before the security level changes.
     /etc/rc.shutdown       Commands run at system shutdown.
     /fastboot              Tells rc not to run fsck(8) during the next boot.
     /var/run/dmesg.boot    copy of dmesg(8) saved by rc at boot time


     sysctl.conf(5), securelevel(7), init(8), netstart(8), rc.conf(8),
     rc.d(8), rc.shutdown(8)


     The rc command appeared in 4.0BSD.

OpenBSD 5.7                      July 22, 2014                     OpenBSD 5.7

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