Router Configurations Required
Making the Server Accessible Over the Internet
If the server is going to be accessed from outside your own locl network, you may need to do some configurations on your router.
- the router will need a fixed IP address, or you will have to communicate the IP address to users whenever it changes and they want to connect. A fixed IP address is SO much easier, but often costs extra.
- the 25565 port should be forewarded to the server where Minecraft Server is running.
Protecting the Server From Access From the Internet
If your server is strictly accessible from within your local network, it is probably a good idea to prevent the Minecraft port from being forewarded to the server (or any other machine).
To do this, make sure that the port 25565 is NOT forwarded to the local network. Make sure that it is neither an explicit foreward, nor contained within a range foreward.