From mboxrd@z Thu Jan  1 00:00:00 1970
From: Anders Fugmann <afu@fugmann.dhs.org>
Subject: Re: "iptables: Invalid argument" with kernel 2.4.20
Date: Tue, 17 Dec 2002 03:19:28 +0100
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To: Rob Sterenborg <rsterenborg@xs4all.nl>
Cc: netfilter@lists.netfilter.org

Rob Sterenborg wrote:
> Could someone tell me when I would want to use "-m udp" ? I searched a
> bit and found a lot of scripts using it but didn't find anything that
> explains it.
The '-m' flag means match extentions. '--protocol udp' implicit loads 
the match extentions for the udp protocol, and thus:
'iptables -p udp', is the same as iptables -p udp -m udp'. See 'match 
extentions' in the iptables manpage for more information.

Regards
Anders Fugmann
--
Author of FIAIF
FIAIF is an intelligent firewall
http://fiaif.fugmann.dhs.org