From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jason Opperisano <opie@817west.com>
Subject: Re: Internal PC/external Gateway
Date: Sat, 14 May 2005 15:00:05 -0400
Message-ID: <20050514190005.GA25010@bender.817west.com>
References: <1116061176.12835.20.camel@debianbox>
	<20050514153608.GA24455@bender.817west.com>
	<1116087634.18707.2.camel@debianbox>
	<20050514164144.GA24669@bender.817west.com>
	<1116090083.18707.6.camel@debianbox>
	<20050514172613.GA24810@bender.817west.com>
	<1116095410.18707.14.camel@debianbox>
Mime-Version: 1.0
Return-path: <netfilter-bounces@lists.netfilter.org>
Content-Disposition: inline
In-Reply-To: <1116095410.18707.14.camel@debianbox>
List-Id: <netfilter.vger.kernel.org>
List-Unsubscribe: <https://lists.netfilter.org/mailman/listinfo/netfilter>,
	<mailto:netfilter-request@lists.netfilter.org?subject=unsubscribe>
List-Archive: </pipermail/netfilter>
List-Post: <mailto:netfilter@lists.netfilter.org>
List-Help: <mailto:netfilter-request@lists.netfilter.org?subject=help>
List-Subscribe: <https://lists.netfilter.org/mailman/listinfo/netfilter>,
	<mailto:netfilter-request@lists.netfilter.org?subject=subscribe>
Sender: netfilter-bounces@lists.netfilter.org
Errors-To: netfilter-bounces@lists.netfilter.org
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
To: netfilter@lists.netfilter.org

On Sat, May 14, 2005 at 09:30:10PM +0300, Sadus . wrote:
> Before continuing, thanks alot for your help.
> 
>                                            +------------+        
>                                            |            |       |
>                                        ----+ Provider 1 +-------
> 192.168.1.2                          |   | 10.2.2.1  |     /
>    PC1__/  \_         +------+-------+ |   +------------+    |
>    _/        \__      |              | |                    /
>   /             \     | 10.2.2.253 | |                    |
>  | Local network -----+Linux GW  eth0|-                     |Internet
>   \_           __/    |192.168.0.141 |                   |
>     \__     __/       |              | |                    \
>    PC2 \___/          +------+-------+ |   +------------+    |
> 192.168.1.3                          |   |            |     \
>                                        ----+ Provider 2 +-------
>                                            |192.168.0.173     |
>                                            +------------+        
> 
> so a little reminder. i just want 192.168.1.3 to take Internet from
> 192.168.0.173
> my GW has as you see has 2 IPs in eth0, and i can reach both of my
> Providers with that setup.
> 
> btw, is there any article to read about the priority of rules while
> writing an iptables script?

yeah--first match wins for all terminating targets.  a good tutorial in
general is:

  http://iptables-tutorial.frozentux.net/iptables-tutorial.html

so it looks like we need:

  iptables -t nat -A POSTROUTING -o eth0 -s 192.168.1.2 \
    -j SNAT --to 10.2.2.253
  iptables -t nat -A POSTROUTING -o eth0 -s 192.168.1.3 \
    -j SNAT --to 192.168.0.141

  echo 202 T2 >> /etc/iproute2/rt_tables

  ip route add default via 192.168.0.173 table T2

  ip rule add from 192.168.1.3 table T2

  ip route flush cache

hope this helps...

-j

--
"Spectator #1: Oh my God. I'm so offended. I'm going to do something
 about this.
 Spectator #2: Mike, there's not really anything you can do.
 Spectator #1: Wow, you're right. I guess I'm just going to have to
 develop a sense of humor, huh?"
        --Family Guy