I'm curious, what's the point of creating an Osu private server? Is it so that you can be ranked number one since there's only you.
Osu, being a single player game, has offline mode, and also online which allows you to play with friends if you want to, so you don't need to go out of your way to setup a LAN network just to match up with friends. I don't see the point in making a private server, please enlighten me, genuinely curious.