====== Init Systems ======

<code>
who -r ctl start                       # get current runlevel
sudo runlevel                          # get current runlevel
</code>

===== systemd =====

==== config files ====

<code>
ls -al /lib/systemd/system/runlevel*
</code>

==== Commands ====

<code>
systemctl start grpwise.service          # start service grpwise
systemctl stop grpwise.service           # stop service grpwise
systemctl status grpwise.service         # show status of service grpwise
systemctl enable grpwise.service         # enable service grpwise
systemctl disable grpwise.service        # disable service grpwise
systemctl get-default                    # get default runlevel
systemctl set-default multi-user.target  # set gui as default (runlevel 3)
systemctl set-default graphical.target   # set cli as default (runlevel 5)
systemctl isolate graphical.target       # switch to gui
systemctl isolate multi-user.target      # switch to cli
systemctl reboot                         # reboot (runlevel 6)
systemctl poweroff                       # shutdown (runlevel 0)
</code>

===== sysvinit =====
==== Commands ====

<code>
chkconfig --list grpwise               # list runlevel of service grpwise
chkconfig --add grpwise                # add service grpwise to all runlevels
chkconfig --del grpwise                # remove service grpwise from all runlevels
chkconfig --level 235 grpwise on       # enable service grpwise on runlevels 2,3,5
chkconfig --level 235 grpwise off      # disable service grpwise on runlevels 2,3,5
</code>