Solaris Run level change

Posted on in Categories News last updated March 3, 2006

Well finally, I have started to use Solaris. Whenever I get different version of UNIX; I need to find out runlevel related information, as you may need to change runlevel for following causes:

  1. Halt/reboot system when shutdown command don’t work
  2. Troubleshooting or repairing system

The first thing I noticed was /etc/inittab file is different from the Linux version. However, runlevel are quite identical

Default Solaris Run Level

  • S : Single user state (useful for recovery)
  • 0 : Access Sun Firmware ( ok> prompt)
  • 1 : System administrator mode
  • 2 : Multi-user w/o NFS
  • 3 : Multi-user with NFS
  • 4 : Unused
  • 5 : Completely shutdown the host (like performing a power-off @ OBP) [ thanks to Marco ]
  • 6 : Reboot but depend upon initdefault entry in /etc/inittab

Solaris Find out runlevel
To find out current runlevel use who command:

$ who -r

Output:

  .       run-level 3  Mar  3 14:04     3      0  S

Solaris changing runlevels after bootup
You need to use init command, for example change runlevel to 2.

# /sbin/init 2

Solaris changing the default runlevel
An entry with initdefault (in /etc/inittab file) is scanned only when init is initially invoked. init uses this entry to determine which run level to enter initially.

Open /etc/inittab file:

# vi /etc/inittab

Find out this entry:

is:3:initdefault:

Change is:3 to number you want, don’t use S, 0, 6 ;). Save file.

See also

  • Read man page of inittab and init for more information.
  • There is also a nice program called runlevel for Solaris.

(Check out all of our posts on Solaris)

Posted by: Vivek Gite

The author is the creator of nixCraft and a seasoned sysadmin and a trainer for the Linux operating system/Unix shell scripting. He has worked with global clients and in various industries, including IT, education, defense and space research, and the nonprofit sector. Follow him on Twitter, Facebook, Google+.

8 comment

  1. Some SysV implementations jump straight from S to their final runlevel… others work their way up from the lower ones. Never assume anything in a lower runlevel is EVER started in any other… always create all the symlinks for everything you want running at each level.

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