Net-Security.org: A guide to System V InitNov 12, 2000, 12:56 (0 Talkback[s])
(Other stories by Aleksandar Stancin)
[ Thanks to LogError for this link. ]
"So here we go again. After you have exorcised all of the daemons that were haunting your system, you might be interested in all of the boring processes that occur when booting your linux. It might seem a bit mystical right now, but it's all quite simple...."
"At the very beginning lets clear out that what we will discuss here concernes only System V Init, so if you're interested in reading more about BSD Init you'll have to do it quietly somewhere else. As most of linux distributions use System V Init (ie, Red Hat, SuSE and etc) I'll make it not only the pin point of this article but devote this entire article to it! Everything you can read in this article has been written with SuSE linux in mind, so please notice that some things may vary from distribution to distribution."
"System V Init uses run levels for determening modes of starting the system and as usual, you'll find that most linux distributions use different systems of run level settings, so it may vary from distribution to distribution. Basically, there are 7 run levels, ranging from 0 to 6. In every distribution run level 0 stands for halt, it stops the system, and run level 6 stands for reboot, and of course it kicks you system with an old John Wayne boot.Other run levels are 1, wich usually but not necessarily stands for single user mode, usually used for administrating the system and other admin related stuff. Other run levels, such as 2, 3, usually stand for full multiuser mode, with or without graphical login. So, let's pretend you wish to switch login from ASCII one to a graphical, and are running SuSE linux...."