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In this howto we will build a load-balanced and high-availability web cluster on 2 real servers with Xen, hearbeat and ldirectord. The cluster will do http, mail, DNS, MySQL database and will be completely monitored. This is currently used on a production server with a couple of websites. The goal of this tutorial is to achieve load balancing & high availability with as few real servers as possible and of course, with open-source software. More servers means more hardware & hosting cost.