[plug] dhcp networking

[Craig Ringer]

> I have a debian box with dhcp installed. and i was wondering how to 
> write a script for my debian client so when my server is turned off it 
> will still have an ip so it can access the rest of my network.
> does anyone have any sujestions on how i might go about this?

You're probably better off just not using DHCP. If you want the rest of 
the network to be contolled using DHCP anyway, then use a static IP on 
those clients that you want to, and make sure you tell the DHCP server 
that there are hosts fixed to those IPs. For example:

host bob {
	fixed-address 192.168.1.4;
}

Personally, I just allocate 192.168.1.100 - 192.168.1.254 to DHCP, and 
anything below that is reserved address space for static hosts. As it 
happens, I still put the static hosts in the DHCP server and have them 
obtain IPs from DHCP, because my server is always on, but it's the same 
idea.

I use a host definition like

host bob {
	fixed-address 192.168.0.4;
	hardware ethernet 00:C0:14:AE:BC:2D;
}

to lock each handed out static address to the appropriate machine's MAC 
address. You can use client-identifiers for this intead, but I find MACs 
to be easier.

Craig Ringer