I am building a PHP based web application, and I want to find out what are the thing I absolutely need to have in order to be ready for anything. Obvious things that come to mind are a db backup every day, code backup, but I really want to have a solid plan.

My server is based on Amazon EC2, so I have a lot of options here. I am planning to use http://www.percona.com/doc/percona-xtrabackup/2.1/ for my db backups, and also to have a slave setup on my master db for replication.

What do you all use when you setup your production servers? Any tips/suggestions would be amazing. Thanks!