GNU/Linux Desktop Survival Guide
by Graham Williams
Cannot Connect to Server
If we get an error indicating that we can not connect to the server, then the likely cause is that the server is behind a firewall that is not allowing connections to the VNC port. This is most likely the case for home based systems with a modem/router. We can modify the router settings to redirect the port connection to the specific host. For example, one router (a Belkin) was configured locally as IP 10.1.1.1 (but had a different ISP provided IP address that was used on the Internet to connect to it) and the computer was configured on the local network with an IP address of 10.1.1.2. The router was configured to redirect requests to connect to port 5900 to 10.1.1.2. Once the router was rebooted the connections via VNC worked just fine.