VServer Setup Hardening

I (@manuelmaly) would wish for a presentation on vServer setup + hardening, because vServers have become cheap options at almost all hosting services, yet it surely is a very bad idea to just slap on some OS, hack Rails and MySQL onto it and press upload - I'm talking of installation issues and security aspects. My usecase would be: Rails (or Java, should be similar) web server with maximum security (yeah I know, there's no "maximum" security :P). The server also hosts a database and SSH server - an all-in-one web server machine, so to say.

Since I'm already making wishes, I would wish for the following setup to be explained:

• CentOS (Linux)
• Apache (for rewriting)
• Ruby & Rails 3
• MySQL or PostgreSQL
• OpenSSH
• Some Firewall (don't know which is advisable)
• Most crucial configuration and hardening actions (block ports, scan packets, remove unnecessary services,...)

I guess most of the installations will require one bash line, what I'm really interested in is the configuration (e.g. Apache rewrites for maintainance etc.). I wouldn't care too much about Mailserver etc., though it would be interesting if it could be squeezed in :)

Please tweet me at @manuelmaly if I have forgotten anything.