A single point of failure is any part of your infrastructure that will cause downtime if it fails. An example would be to use one server to host both your web server and your database. Outages are often caused by these single points of failure and we want to design our infrastructure to avoid these situations.
A highly available infrastructure has no single point of failure. Commonly, this means that your infrastructure is divided by service and running each service on more than one server. If one server fails, there are other servers available to process requests. A highly available configuration is not only important for redundancy, it will be faster and more cost effective to scale your infrastructure as well.
Skunkworks can facilitate a High Availability configuration utilizing Load Balancers for any website. Be forewarned however. It's not easy, quick, or cheap.
High Availability Diagram
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