I am running a Windows Server 2008 R2 with 3 nics (2 with external IPs, 1 with internal IP). The two external IPs are associated with two web sites running on that server. The third nic is for communication with a backend server. Everything is working fine, both website are reachable from outside. Now I need my backend server to make a connection to the outside world. To do this I activated and configured NAT on my described web server.
Now the Problem: when activating NAT, one of the external IP adresses becomes unreachable. Deactivating NAT makes the second external IP again reachable. Tatally repoducable!
What shoud I do? I need both external IPs and the NAT Function! Can somebody help me out??