Chapter 3. Patterns for High Availability

A very important topic, for most operations teams, is how to keep the systems responsive. Many things can cause an application to behave improperly with the end user, and there are a lot of different methods to handle these issues. The types of preventive measures used depend heavily on the purpose of that application in the system. Many applications are moving towards a microservice approach, in which the system is divided into smaller subsystems that have one task. This microservice approach is similar to software development life cycles, in which large sections of code are divided into smaller sections. This breaking up of responsibilities makes testing them a bit simpler in that each subsystem has a very specific and predictable job. Another benefit from an operational standpoint is that the system can be scaled horizontally, depending on which part is the bottleneck.

Breaking up the application into scalable pieces creates an issue...