What IP address do I tell Serv-U to use?
Generally, it’s recommended that you leave this field blank, which tells Serv-U to use any available IP address. When setting up Serv-U on a home network with a router, your computer will only have a single internal (LAN) IP address anyway. The only time you may wish to enter an IP address here is when the computer possesses multiple network interfaces and you wish to limit Serv-U’s activity to one of these interfaces.