[torinmr]

The SRE Book (http://shop.oreilly.com/product/0636920041528.do) has a number of chapters on load balancing that are well worth reading.

One thing that the book covers that I think this article glossed over was the fact that in sufficiently large systems there's never a single "load balancer" - instead there's many layers of load balancing systems at different levels of the stack. E.g.:

DNS load balancing -> high capacity network-level load balancing -> shared reverse HTTP proxy -> application server -> database (with a "load balancer" internal to the application server load balancing among DB replicas).

[peterwwillis]

They mention there are different applications for load balancers, and then use one or two examples. But their main points are the most important ones: if you don't know what you're using it for, it might be worthless.

The SRE book seems to only have a couple sub-chapters on it, so I would recommend looking up white papers and best practices for your particular application of load balancing. Safari Books has over 17,000 matches for "load balancing" in its library, for example, and F5 has 12 white papers on it just for their products.