From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rowan Reid <rreid@studio3arc.com>
Subject: RE: How filter IP address if it *changes* often?? (think dhcp)
Date: Wed, 28 Mar 2001 08:51:59 -0800
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To: seberino@spawar.navy.mil, netfilter@lists.netfilter.org


> How do this if IP address changes uncontrollably
> like with DHCP??


The following sh script will extract the ip address of the external
interface. If the address changes forcable ie not just when you renew
your lease volentarily then run the script on cron

$IFCONFIG = /path/ifconfig
$EXTIF = ppp0 or whatever
$AWK=/patch/awk

EXTIP="`$IFCONFIG $EXTIF | $AWK \
 /$EXTIF/'{next}//{split($0,a,":");split(a[2],a," ");print a[1];exit}'`"