Amazon Web Services For Dummies

Chapter 14

Ten Design Principles for Cloud Applications

Those in the know will tell you that you have to use the right tool for the job. For the new generation of webscale applications like Pinterest, AWS is the right tool. Overlooked in that truism is the undeniable fact that using a tool effectively requires having the right skills. With respect to AWS, the right skills involve aligning your application design with AWS’s operational characteristics. It’s critical to get the application design right — so here are ten design principles to help you get your alignment straight.

Everything Fails All the Time

The truism “Everything fails all the time” is adapted from Werner Vogels, the chief technology officer of Amazon. IT departments have traditionally attempted to render both infrastructure and applications impervious to failure: A hardware resource or an application component that “fell down on the job” increased the urgency of the search for perfection in order to banish failure. Unfortunately, that search was never successful — the failure of resources and applications has been part of the IT world from the beginning.

Amazon starts from a different perspective, borne of its experience as the world’s largest online retailer and as one of the largest webscale companies worldwide. When you run data centers containing thousands of servers and tens of thousands of disk drives, resource failure is a daily occurrence. And when a hardware resource fails, the software or data residing ...