Congratulations! If you’re reading this, you’re likely the proud owner of a website that’s crossed into the territory of requiring either high-availability or additional performance.
Let’s assume, for the sake of this example, your web tier is running .NET and your database is running on a separate stand-alone server. If you’re still running both your web and DB tier on the same server, you should separate those roles before reading any further. The methods for scaling a web tier are generally not compatible with having a combined web/db tier.
Whether the goal is reliability, performance, or both, you’re going to need some way of balancing or directing incoming load to your web site across multiple servers. This is generally done with a hardware load balancer. It can also be accomplished through many varieties of software load balancing or DNS tricks, but there are many limitations you’ll face.
