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:
- Halt/reboot system when shutdown command don’t work
- 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)
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{ 8 comments… read them below or add one }
The run level 5 completely shutdown the host (like performing a power-off @ OBP)
I like your blog!
Regards
Marco
I was just wondering about run level 5, under Linux it is for X window.
Thanks Marco!
Hi,
I’d like to know about the previos run-level when doing “who -r”
Why previous run=level is S
Why not 2? since we’re currently on 3.
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.
can i have my oown run levels?
Are runlevel S and 1 not same ???
Yes, Run levels S and 1 are not same… because 1 is a numeric number and S is alphabet.
Way to answer a 3 and a half year old question