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I've got a little question about Masquerading and SNAT in combination with shorwall and KVM. The Operating System is Scientific Linux 6.4.

Setup is like this at my root server:

  • Virtual Machine IP
  • Standard Gateway of VM: (Firewall int_net)
  • "wan" interface ip of the firewall: (virbr0_net)
  • Default Route for the Gateway for Internet: (virbr0)
  • eth0 has three public ip-adresses at eth0:1 eth0:2 eth0:3 and is directly connected to the internet.

The outgoing traffic of the VM will be NATed so the packets will come in at virbr0 with the source-ip and will be NATed to the internet with the src-ip of eth0. I would like to have the opportunity to let outgoiging packets of ( firewall-wan-if_ip) to get the external IP of eth0:1 for example.

How could I do that best way? Any advice?

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