Talk:Runlevel

On proposed merger with RL3
The only thing I have to say is that it's nice to get a quick definition if you're just curoius. The link to runlevel is there if you need more info. --AlanH 22:29, 28 January 2006 (UTC)

Ubuntu and Upstart
While ubuntu does use upstart, runlevels still play an important role. Single user mode is still accessed with "sudo init 1" and startup/shutdown scripts are placed in respective rc directories.

The section IMHO should say ubuntu uses upstart and its init levels are the same as debians (as it did before).

I would do it myself but I am unsure of how accurate I am and I am not knowledgeable enough to talk about init. --Sish 04:36, 29 May 2007 (UTC)

Purpose of run level 4
Run level 4 is for "turnkey" UNIX systems, such as AT&T's telephone switches. In a modern context an Pizza shop application would boot into run level 4. If the system is swapped out for diagnosis then the programmers can boot the machine into run level 3 or 5 for the standard multiuser development environment. I've got an old Bell System paper on System V Init which describes this, I'll see if I can find it.Gdt 12:53, 15 November 2007 (UTC)

Discussion about merging runlevel and init
I don't think they should be merged even they are so related they are not the same. Callmejosh (talk) 08:01, 6 September 2008 (UTC)

Runlevels a, b and c
What about runlevels a, b and c? They're called "on-demand" by, but the manual doesn't clarify what they're supposed to be used for. Does anyone have any documentation on those? --Wtrmute (talk) 19:05, 31 July 2009 (UTC)


 * To quote from a System V administrator's manual from 1982 - look for "INIT (1M)":


 * Telinit, which is linked to /etc/init, is used to direct the actions of init. It takes a one character argument and signals init via the kill system call to perform the appropriate action. The following arguments serve as directives to init.
 * a,b,c tells init to process only those /etc/inittab file entries having the a, b or c run-level set.
 * a,b,c tells init to process only those /etc/inittab file entries having the a, b or c run-level set.
 * a,b,c tells init to process only those /etc/inittab file entries having the a, b or c run-level set.
 * a,b,c tells init to process only those /etc/inittab file entries having the a, b or c run-level set.


 * and to quote from a System V administrator's manual from the same manual set - look for "INITTAB(4)" (yes, it's silly that it's in the user's manual; I guess they didn't bother having a separate "4M" section, in the administrator's manual, for files used only by administrators):


 * There are three other values, a, b and c, which can appear in the rstate field, even though they are not true run-levels. Entries which have these characters in the rstate field are processed only when the telinit (see init(1M)) process requests them to be run (regardless of the current run-level of the system). They differ from run-levels in that the system is only in these states for as long as it takes to execute all the entries associated with the states. A process started by an a, b or c command is not killed when init changes levels. They are only killed if their line in /etc/inittab is marked off in the action field, their line is deleted entirely from /etc/inittab, or init goes into the SINGLE USER state.


 * So those are for "one-shot" running of processes from init. Guy Harris (talk) 19:34, 23 March 2019 (UTC)

RL 0-9
Which OS has runlevels 0 to 9? --Vssun (talk) 08:14, 20 August 2011 (UTC)


 * I have added runlevels to my systems so I have 0 to 8. 81.228.219.220 (talk) 16:55, 3 June 2016 (UTC)

Arch Linux runlevels
With Arch fully switched to systemd, it no longer has runlevels by default. — Preceding unsigned comment added by 146.145.85.49 (talk) 23:50, 6 February 2013 (UTC)