Sometimes there is an urgent need for creating an exact duplicate or "mirror" of a web site on a separate server. This could be needed for creating Round Robin Setups, Load-Balancing, Failovers, or for just plain vanilla backups. In the past I have used a lot of different methods to copy data from one server to another, including creating an archive of the whole directory and then using scp to send the file over, creating an archive and then encrypting it and then sending that file over using ftp, curl, etc., and my persistence at learning new ways to do things has paid off because now I use rsync to keep an exact replica of the entire directory on an external server, without having to use all the CPU and resources of other mirroring methods.


This is all new, experimental, and very very cool. It literally uses .htaccess techniques to create several virtual "locked gates" that require a specific key to unlock, in a specific order that cannot be bypassed. It uses whitelisting .htaccess tricks to specify exactly what is allowed, instead of trying to specify everything that isn't allowed. Also, by setting specific cookies/tokens after successfully passing through a gate, we can then require the exact cookie/token from the previous gate, which stops an attacker from skipping or bypassing gates.