Sorry to have to put new life in this thread but I do have the same problem and 1:Many NAT is not the solution.   My scenario is that I have on the Sophos firewall certain internal vlans masquerading out as specific external IPs e.g. internal vlan 1.2.3.x looks like 300.100.100.1 and vlan 1.2.4.x looks like 300.100.100.2 where 300.100.100.1 and 2 are additional public IPs ... this is just a representation, 300.x is just a # 🙂    Then in our cloud systems we use these IPs to help with traffic filtering without having to do VPNs.   Is there another way besides the two external interfaces to have masquerading of these Public IPs?   thx MP ... View more