Solaris Runlevels

     S     Single user state (useful for recovery)

    0     Go into firmware.

    1     Put the system in system administrator mode. All local
          file  systems  are mounted. Only a small set of essen-
          tial kernel processes are left running. This  mode  is
          for  administrative  tasks such as installing optional
          utility packages. All  files  are  accessible  and  no
          users are logged in on the system.

    2     Put the system  in  multi-user  mode.  All  multi-user
          environment   terminal   processes   and  daemons  are
          spawned. This state is commonly  referred  to  as  the
          multi-user state.

    3     Extend  multi-user  mode  by  making  local  resources
          available over the network.

    4     Is available to be defined as  an  alternative  multi-
          user  environment  configuration.  It is not necessary
          for system operation and is usually not used.

    5     Shut the machine down so that it is safe to remove the
          power. Have the machine remove power, if possible.

    6     Stop the operating system  and  reboot  to  the  state
          defined by the initdefault entry in /etc/inittab.