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 10.16.16.30
- Standard Gateway of VM: 10.16.16.254 (Firewall int_net)
- "wan" interface ip of the firewall: 192.168.122.254 (virbr0_net)
- Default Route for the Gateway for Internet: 192.168.122.1 (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 10.16.16.30 will be NATed so the packets will come in at virbr0 with the source-ip 192.168.122.254 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 192.168.122.254 ( firewall-wan-if_ip) to get the external IP of eth0:1 for example.
How could I do that best way? Any advice?