Dual load balancer (one failsafe)?

[Floren Munteanu]

More thoughts on that, related to Heartbeat usage:
http://affectioncode.wordpress.com/2008/06/11/comparing-nginx-and-haproxy-for-web-applications/

The problem is the proxy load balancing algorithm. Nginx only comes with a round-robin balancer and a hash-based balancer. Only the former is of interest to us since our object is to distribute the load evenly across a pack of Mongrel back ends. The round-robin algorithm is often an acceptable tool: if every request finishes within a few milliseconds, there’s no problem.

But if a page takes a while to load, Nginx will start routing requests to backends that are already processing requests — as a result, some backends will be queuing up requests while some backends will remain idle. You will get an uneven load distribution, and the unevenness will increase with the amount of load subject to the load-balancer.

So I think a more suitable software would be HaProxy, instead of Heartbeat.
I plan to serve PHP mixed with static files, on all nodes.