The main function is to set up a server in the local area network, because all computers in the local area network are connected to the Internet by public IP. Therefore, when users use public ip to access the server, they need to specify the computer IP in the local area network.

For example, the default port of SQL server is 1433, for example, the public ip is 10.0. 1, and the LAN server IP is 192.5438+068.0.250.

Then you need to set the port forwarding: external port: 1433, internal port: 1433, internal IP: 192.6438+068.0.250.

In this way, using 10.0. 1, 1433 to access SQL server will connect the service of 192.438+068.0.250.