[alphadeity]

I have my servers setup in a cluster. I have 5 servers total in this cluster. I reccomend that you go dedicated instead of vps.

Server1 (Webserver) - Nothing else installed.

Server2 (MySQL Server) - Nothing else installed!

Server3 (MySQL replica Server) - Nothing else installed, replicates the MySQL databases from server2 every 3 hours. If server2 goes down, server3 will act as the master server. Some information will be last, but not completely. The delay is there in case server2 is attacked... the delay will hopefully be enough time to stop server3 from replicating the attack. (be careful how you setup database replication as it can cause bad delay times on your forums).

Server4 (Email Server) - Email only! Does nothing else.

Server5 (Raided backup of server 1, 2, 3, and 4) - This does not have anything installed. It does backups every night.

The only server that has access to the outside internet is server1 and server4. Just make sure that server1, server2, and server5 are nice and beefy. I really only reccomend having a setup like this if you're a host. :-P