Re: Two netwok cards to access the internet.

[Sertys <sertys@supportivo.org>]

On Tue, 22 Mar 2005 18:54:26 -0300, Sebastião Antônio Campos  
<sa.campos@datasulsp.com.br> wrote:

Well, that's easy. When you know the ports you want to map through the  
interfaces, just do

iptables -t nat -A POSTROUTING -m multiport -p tcp -s 172.17.1.8 --dports  
25,110,1723,1701,47 -o eth0 -j MASQUERADE
iptables -t nat -A POSTROUTING -s 172.17.0.0/16 -o eth2 -j MASQUERADE
or even better
iptables -t nat -A POSTROUTING -s 172.17.0.0/16 -o eth2 -j SNAT  
--to-source $ETH2_IP

Those are simple states, you might add --syn or -m state, it's a choice of  
yours anyway.


> Hi!
>
> I have the following:
>
> A RedHat 9.0 with 3 Network cards: One we use in local network (eth1)  
> and the other (eth0 and eth2)  to access the internet.
>
> I'd like to separate the traffic. In the eth0 use only with the e-mail  
> server (pop, smtp, 1723, 1701 and protocol 47) and the eht0 with others  
> traffis (http, https, msn....).
>
> I tried
>
> iptables -t nat -A POSTROUTING -o eth2 -s 172.17.1.8 -j MASQUERADE    
> (--this ip addrs is pop and smtp server)
> iptables -t nat -A POSTROUTING -o eth0 -s 172.17.0.0/16 -j MASQUERADE
>
> But when I did this I could not access the port 1723, 1701 and protocol  
> 47 using the eth2.
>
> I tried too use only iptables -t nat -A POSTROUTING -o eth2 -s  
> 172.17.0.0/16 -j MASQUERADE
>
> And I got the same prob.
>
> If I use iptables -t nat -A POSTROUTING  -s 172.17.0.0/16 -j MASQUERADE
>
> I will get a success access. Only when I use iptables -t nat -A  
> POSTROUTING  -s 172.17.0.0/16 -j MASQUERADE (without -o eth2 or -o eth0).
>
>
> Who could help me?
>
> Thanks
>
>
> Sebastiгo Antфnio Campos
> Infojoi Computadores Ltda
> Joinville -SC - R. Iririъ, 3587
> Cml. (47) 437-0796 - Cel. (47) 9927-5349
> tiao@infojoi.com.br
> http://www.lupusnet.com.br



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