topic Re: Equivalent to /etc/inittab in Operating System - Linux

Equivalent to /etc/inittab

skt_skt — Thu, 24 Jan 2008 20:44:26 GMT

Is there an an equivalne file in Linux to /etc/inittab of hp-UX to specify the run level(like single user mode), other than /etc/grub.conf.

Re: Equivalent to /etc/inittab

Ivan Ferreira — Thu, 24 Jan 2008 20:49:17 GMT

Linux also uses /etc/inittab and you can specify there the runlevel in the line initdefault.

What Linux distribution?

Re: Equivalent to /etc/inittab

TwoProc — Thu, 24 Jan 2008 21:23:15 GMT

Well... there's /etc/inittab. :-)

At least in RH there is. What version of Linux are you on? I think that maybe some Debian variants (if I remember correctly, but it's been a while) don't use it though.

What version are you speaking of?

Re: Equivalent to /etc/inittab

Stuart Browne — Thu, 24 Jan 2008 23:01:17 GMT

All major linux varients I've come across on a PC/Server/Desktop type platform use an 'inittab'.

The 'id:X:initdefault:' line specifies the default run level.

Re: Equivalent to /etc/inittab

Mike Stroyan — Fri, 25 Jan 2008 02:20:53 GMT

Ubuntu uses 'upstart' instead of sysvinit and /etc/inittab.
http://en.wikipedia.org/wiki/Upstart

Upstart is configured by files in /etc/event.d/. The /etc/event.d/rc-default script selects the default level. That script still looks at /etc/inittab and the initdefault setting.

Re: Equivalent to /etc/inittab

dirk dierickx — Fri, 25 Jan 2008 09:30:54 GMT

grub is not the same thing as init/upstart and the config file inittab.

grub is the boot manager of linux, compare it with ISL on HPUX.

just to be sure you know.

Re: Equivalent to /etc/inittab

Huc_1 — Fri, 25 Jan 2008 11:01:23 GMT

In /etc/inittab change the following line to the level you want here it is level 5

id:5:initdefault:

If you want it to level 1 (single user) use

id:1:initdefault:

But this is usualy not done like this but at boot time at the console by interrupting grub
just type then

Select the line that starts with kernel you want and type e to edit the line.

Go to the end of the line and type single or 1 as a separate word (press the [Spacebar] and then type single or 1). Press [Enter] to exit edit mode.

Back at the GRUB screen, type b to boot into single user mode.

this will get you in single user mode for just this one boot if you need to be more permanent ie at each boot you could write this into the file /boot/grub/menu.lst

when your are in single user mode you need to manualy type a d to execute the rest of startup...

this will then execute your /etc/inittab to the level you specified there...

Hope this is what you needed

enjoy life.

Jean-Pierre Huc

Re: Equivalent to /etc/inittab

~sesh — Fri, 25 Jan 2008 12:37:40 GMT

The /etc/inittab file is present in Linux also. I'm not sure if it has a similar format as HP-UX.

id:X:initdefault: is the line specifies the default run-level that the system will boot into.

grub.conf or editing the boot options during the Grub loader will also help you boot into the run-level you would like.

Re: Equivalent to /etc/inittab

skt_skt — Fri, 25 Jan 2008 13:57:25 GMT

is there a harm in inittab method compare to gur.conf method to boot in single user mode.

Later (once in single user mode)update the inittab to normal run level and doing ctrl+d..

Re: Equivalent to /etc/inittab

Alexander Chuzhoy — Fri, 25 Jan 2008 14:31:32 GMT

No harm, but it is less common to specify the default runlevel in grub.conf.

Re: Equivalent to /etc/inittab

Huc_1 — Sat, 26 Jan 2008 12:48:55 GMT

No

But the think to point out is if you put Single in /boot/grub/menu.lst and single is the level you want to work most of the time then d is not needed... if there is a difference between /boot/grub/menu.lst and /etc/inittab, and this usually the case

like from 1 in menu.lst with 5 in /etc/inittab then a d will move you on to level 5

So passing 1 or single to grub should be seen as a way to interrupt full boot (that is to a level higher then single or 1.

Hope I did manage to help.

enjoy life.

Jean-Pierre Huc

Re: Equivalent to /etc/inittab

skt_skt — Wed, 30 Jan 2008 00:08:32 GMT

closing