Setting Up A High-Availability Load Balancer (With Failover and Session Support) With HAProxy/Heartbeat On Fedora 8

This document describes how to set up a two-node load balancer in an active/passive configuration with HAProxy and heartbeat on Fedora 8. The load balancer acts between the user and two (or more) Apache web servers that hold the same content. The load balancer passes the requests to the web servers and it also checks their health. If one of them is down, all requests will automatically be redirected to the remaining web server(s). In addition to that, the two load balancer nodes monitor each other using heartbeat. If the master fails, the slave becomes the master - users won't notice any disruption of the service. HAProxy is session-aware - you can use it with any web application that makes use of sessions like forums, shopping carts, etc.