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Old 10-10-2007, 08:08 AM   #1
Registered: Jan 2001
Location: Ljubljana Slovenija
Distribution: Slackware
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DHCP for multiple subnets


This might already be asked but i did not find the answer.

So my situation is this, i use 1 DHCP server on subet (ip, my firewall has 3 network cards inside (1 ext, and 2 internals - and, and i would like that my DHCP would serve both subnets (by making two scoopes).
So basically i would need to forward DHCP requests from sub net to DHCP server (, now i'm using iptables on my firewall and would need to forward this requests but no matter how i try i'm unable to succeed.

I hope this makes a little sense what i'm trying to ask.

Thank you in advance,


Last edited by PcHammer; 10-10-2007 at 08:42 AM.
Old 10-10-2007, 10:31 AM   #2
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I think you will need a DHCP relay agent..

the relay agent will catch the DHCP request broadcasts from the client and forward them directly to the DHCP server. the server will respond with the appropriate address for the subnet the request came from, and return that address to the agent. which in turn completes the DHCP process with the client.

(Cisco calls this an 'IP helper address' in their terminology)
Old 10-11-2007, 04:01 AM   #3
Registered: Jan 2001
Location: Ljubljana Slovenija
Distribution: Slackware
Posts: 70

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Thank you so much, its working like it should.


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