Introduction

Let's take a moment to reflect on our progress through this series of chapters beginning from Chapter 11, Build Your Own HA Cluster. We started by setting up a Kubernetes cluster using kops to configure AWS infrastructure in a highly available manner. Then, we used Terraform and some scripting to improve the stability of our cluster and deploy our simple counter app. After this, we began hardening the security and increasing the availability of our app using Kubernetes/cloud-native principles. Finally, we learned how to run a stateful database responsible for using transactions to ensure that we always get a series of increasing numbers from our application.

In this chapter, we are going to explore how to leverage the data that already exists in Kubernetes about our applications to drive and automate decision-making processes around scaling them so that they are always the right size for our load. Because it takes time to observe application metrics, schedule...