I am aware there are various ways of starting and stopping services. I am using Red Hat and am learning on securing my box via command line. I have learn that I can use ntsysv or /usr/sbin/setup or manually edit the rc*.d files. Now what I started comparing what I did via ntsysv against rc3.d. I notice that each service is denoted with a number e.g. S05kudzu which starts kudzu during the boot up process of Linux. Now if I turn off kudzu via ntsysv it changes the denotion to K95kudzu. I'm confused. I thought to turn off services I simply replace the capitalised "S" with "s". Adding further to my confusion is how did S05kudzu become K95kudzu and what I am emphasizing on is the number "05" and "95". Can anyone explain to me why 'K" is used in place of "s" and how does one denote the numbering of these services?

Thanks!

In each n-runlevel (rcn.d), some "services" (which actually are scripts who execute services or commands) are started and some are killed. Some distributions, like Debian, actually "jumps" some runlevels (if I'm not wrong, from 3 to 5) because it's more quick to start the system that way.

In /etc/rcn.d/ you will find some symbolic links to scripts in /etc/init.d. Those links are named S** or K**. That means that they are being Started or Killed in that runlevel. The two following numbers are telling init in which order they are being started (or killed). Sometimes, a script which is runned first is going to be killed last (in some way, scripts might need 'dependencies' and that's what the order says).

It's ok to have two Sxx or Kxx with the same numbers (when one adds a script which doesn't need others to be runned, one probably will link it as S99 or K99 -start and kill at last-).

Thank you for your help