[oceanic]

Nice diagram, I'm borrowing it as a reference for the setup I'm going to be designing for work soon :-)

Did you consider running nginx for your PHP application servers as well?

Also, can I ask what sort of traffic you get per {{ time period }} ??

[smusumeche]

Not that much. Apache gets about 30-40 requests per second on average. However, this is with Varnish handling a lot of requests that never get sent to the backend.