Services

Les services (daemon)

Les services permettent de lancer ou non un programme en démon lors du démarrage du serveur ou d'un changement de level (runlevel).

Debian

• http://wiki.debian.org/fr/SysVInit
• Debian/SysVinit : Utilitaires d'initialisation à la System-V
• System run levels and init.d scripts

Utilisez la commande update-rc.d pour créer les liens symboliques dans le bon /etc/rc?.d

Pour connaitre la liste des services de votre Debian, vous pouvez le faire en regardant votre runlevel et en listant les liens symboliques :

# runlevel
N 2
# cd /etc/rc2.d/
# ls -al
total 12
-rw-r--r--  1 root root  556 aoû 12  2008 README
lrwxrwxrwx  1 root root   17 aoû  4 12:54 S10rsyslog -> ../init.d/rsyslog
lrwxrwxrwx  1 root root   15 aoû  4 12:55 S12acpid -> ../init.d/acpid
lrwxrwxrwx  1 root root   15 aoû  4 14:22 S15bind9 -> ../init.d/bind9
lrwxrwxrwx  1 root root   16 aoû  4 14:22 S15lwresd -> ../init.d/lwresd
lrwxrwxrwx  1 root root   13 aoû  4 16:37 S16ssh -> ../init.d/ssh
lrwxrwxrwx  1 root root   15 aoû  4 14:22 S20exim4 -> ../init.d/exim4
lrwxrwxrwx  1 root root   20 aoû  4 14:22 S20nfs-common -> ../init.d/nfs-common
lrwxrwxrwx  1 root root   23 aoû  4 14:22 S20openbsd-inetd -> ../init.d/openbsd-inetd
lrwxrwxrwx  1 root root   15 aoû  4 16:47 S20rsync -> ../init.d/rsync
lrwxrwxrwx  1 root root   13 aoû  4 16:47 S23ntp -> ../init.d/ntp
lrwxrwxrwx  1 root root   13 aoû  4 14:22 S89atd -> ../init.d/atd
lrwxrwxrwx  1 root root   14 aoû  4 12:54 S89cron -> ../init.d/cron
lrwxrwxrwx  1 root root   17 aoû  4 14:22 S91apache2 -> ../init.d/apache2
lrwxrwxrwx  1 root root   18 aoû  4 12:54 S99rc.local -> ../init.d/rc.local
lrwxrwxrwx  1 root root   19 aoû  4 12:54 S99rmnologin -> ../init.d/rmnologin
lrwxrwxrwx  1 root root   23 aoû  4 12:54 S99stop-bootlogd -> ../init.d/stop-bootlogd

Le README contient :

The scripts in this directory are executed each time the system enters
this runlevel.

The scripts are all symbolic links whose targets are located in
/etc/init.d/ .

To disable a service in this runlevel, rename its script in this directory
so that the new name begins with a 'K' and a two-digit number, where the
number is the difference between the two-digit number following the 'S'
in its current name, and 100.  To re-enable the service, rename the script
back to its original name beginning with 'S'.

For a more information see /etc/init.d/README.

La commande update-rc.d

# update-rc.d
usage: update-rc.d [-n] [-f] <basename> remove
      update-rc.d [-n] <basename> defaults [NN | SS KK]
      update-rc.d [-n] <basename> start|stop NN runlvl [runlvl] [...] .
               -n: not really
               -f: force

update-rc.d rsync defaults
update-rc.d rsync remove

# update-rc.d rsync defaults
System startup links for /etc/init.d/rsync already exist.
# update-rc.d rsync remove
update-rc.d: /etc/init.d/rsync exists during rc.d purge (use -f to force)
# update-rc.d -f rsync remove
Removing any system startup links for /etc/init.d/rsync ...
  /etc/rc0.d/K20rsync
  /etc/rc1.d/K20rsync
  /etc/rc2.d/S20rsync
  /etc/rc3.d/S20rsync
  /etc/rc4.d/S20rsync
  /etc/rc5.d/S20rsync
  /etc/rc6.d/K20rsync
# update-rc.d rsync defaults
Adding system startup for /etc/init.d/rsync ...
  /etc/rc0.d/K20rsync -> ../init.d/rsync
  /etc/rc1.d/K20rsync -> ../init.d/rsync
  /etc/rc6.d/K20rsync -> ../init.d/rsync
  /etc/rc2.d/S20rsync -> ../init.d/rsync
  /etc/rc3.d/S20rsync -> ../init.d/rsync
  /etc/rc4.d/S20rsync -> ../init.d/rsync
  /etc/rc5.d/S20rsync -> ../init.d/rsync

REHL

chkconfig