From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?utf-8?q?O=C4=9Fuz_Yar=C4=B1mtepe?= <comp.ogz@gmail.com>
Subject: prerouting and route
Date: Sat, 29 Sep 2007 23:23:12 +0300
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To: netfilter@vger.kernel.org

Hi,

I gave some points that i couldnt visualize.=20
=46irst question is related with the route command. Lets say i defined =
a local=20
route as,

route add 10.2.0.0 netmask 255.255.255.0 gw 10.2.0.1 dev eth1

and while i am configuring iptables i wrote some rules:

# delete all existing rules
iptables -F
iptables -t nat -F
iptables -t mangle -F
iptables -X

# set default policies
iptables -P INPUT DROP
iptables -P FORWARD DROP

iptables -t nat -A PREROUTING -i eth0 -p ALL -d 10.2.0.0/24 -j DNAT --t=
o=20
10.2.0.1

At this point i ask myself whether i need this rule, because i had alre=
ady=20
defined a route while configuring interfaces. So is there a relation be=
tween=20
route definitions and prerouting, is it unnecessary to define a local r=
oute=20
and try to the same thing with iptables?

Second, i have a rule as,

iptables -t nat -A PREROUTING -i eth1 -p ALL  -j DNAT --to 192.168.1.4

192.168.1.4 is the ip of eth0 which is plugged to a gateway with the ip=
=20
192.168.1.3. If i send a package from eth1 to lets say 192.168.1.10, it=
s=20
destination address is replaced with 192.168.1.4. After this point, wil=
l it=20
continue to 192.168.1.3? If yes how?

Thanx.
=20
--=20
O=C4=9Fuz Yar=C4=B1mtepe
http://www.yarimtepe.com/en