Hi, my old dlink router died so I got a AirPort Extreme to replace it. I have a old Mac mini which I use as a media server, since this is on 24/7 I'd like to stop this accessing the Internet and limit it to just my local network. I can't seem to figure out how to do this and the airport utility app is very basic and offers little control. It seems that if I limit Internet access then it stops local network access too. Any tips? Thanks.