Re: Dynamic IP's & Iptables

From: Kasper Dupont (
Date: 04/17/03

From: Kasper Dupont <>
Date: Thu, 17 Apr 2003 01:17:22 +0200

comaxco wrote:
> I have a standalone Linux (8.0 RH) based firewall/router that worked
> just fine with static IP adresses. Circumstances now require that I
> use ATT broadband with a cable modem and ATT broadband only deals in
> dynamic IP adresses. Is there any way I can get my IPtables code to
> handle dynamic IP's since it appears that I am now assigned a new IP
> adress about every 24 hours?

You can surely use iptables with dynamic IP address with no major
problems. Of course all open connections will be broken when the IP
changes. Your ruleset should not include your IP anywhere. AFAIK you
can write almost anything without specifically having the IP in the
rules. You might need to use MASQUERAD and REDIRECT rather than SNAT
and DNAT in some places.

Kasper Dupont -- der bruger for meget tid på usenet.
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