The first thing we need to do, is to send a customer message to SAP Support (component XX-SER-NET-OSS-NEW) and tell them to register the hostname and IP of our new Saprouter. (In our case it is system name (hostname) = " **"and Public Ip =*******) We have to register it with the official IP address (no internal IPs allowed), but it's allowed to use NAT in the firewall/router. Ports to be allowed..