A superb explanation by Theo Schlossnagle of how to deploy a high availability load balanced system using mod backhand and Wackamole. The idea is you don't need to buy expensive redundant hardware load balancers, you can make use of the hosts you already have to the same effect. The discussion of using peer-based HA solutions versus a single front-end HA device is well worth the read. Another interesting perspective in the document is to view load balancing as a resource allocation problem. There's also a nice discussion of the negative of effect of keep-alives on performance.
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