From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Daniel F. Chief Security Engineer -" Subject: NAT and anti spoofing Date: Wed, 18 Sep 2002 16:29:56 -0500 Sender: netfilter-admin@lists.netfilter.org Message-ID: <200209181629.56408.danielf@supportteam.net> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: Errors-To: netfilter-admin@lists.netfilter.org List-Help: List-Post: List-Subscribe: , List-Id: List-Unsubscribe: , List-Archive: Content-Type: text/plain; charset="us-ascii" To: netfilter This may be a stupid question but the answer is eluding me right now. With NAT setup. I have a single machine with 8 global IPs NATed to 8 10.0.0.0/8 IPs. How do you filter the 10.0.0.0/8 network from talking to the machines behind the firewall. From outside the firewall on the internet. I used command like this to get the NAT working is this right. iptables -t nat -A POSTROUTING -s 10.10.10.128 -j SNAT --to 1.2.3.4 iptables -t nat -A PREROUTING -d 1.2.3.4 -j DNAT --to 10.10.10.128 This worked to make 1.2.3.4 send to a machine behind the firewall that had 10.10.10.128 for it's IP. Thanks -- Daniel Fairchild C I Host | danielf@cihost.com