I am new to linux/debian. I am trying to figure out where during boot is the network configuration taking place.
From reading, I know that /etc/network/interfaces is the configuration file for ifup and ifdown and the changes I make are working but I can't seem to figure out when are these commands called during bootup.
Thanks,
Shahim

what are you trying to change in the boot-up?

They are called in /etc/init.d/networking

Specifically line 124:

       echo -n "Configuring network interfaces: "
       ifup -a
       echo "done."

Bill Clinton

Bill,

I don't have a link in rc2.d to /etc/init.d/networking. Does it get called from anywher else?

Shahim

By default in Debian, the network is started in runlevel 0.

Specifically, /etc/rc0.d/S35networking is a symlink to /etc/init.d/networking.

Isn't run level 0 used to halt the system? I am new to linux and appreciate your answers.

Other distributions may be different; I've really only had much experience with Gentoo and Debian.

My understanding is that when you boot up in runlevel 2 (or whatever) you've run all the lower runlevels in order. So on startup, all the files in rc0.d starting with S are run, then the ones in rc1.d, etc. When a runlevel is exited the K files are run in the reverse order.

If anybody knows this is wrong, please correct me, but AFAIK that's how Debian handles startup and shutdown.

After some reading I think I found the answer.
First, inittab is ran, during that /etc/init.d/rcS is called.
rcS calls all the S scripts in /ect/rcS.d/ directory which does have a link to /etc/init.d/networking and some other links.

The other rc?.d directories are only called at their level.

link: http://www.debian.org/doc/debian-policy ... tml#s9.3.4

If I am wrong please correct me.

Great reference there. Should have checked for one myself first. Looks like your reading is spot on.

Thanks for the education!