Migrating Containerized Application to Kubernetes
In the previous chapter, we built a simple HTTP server called k8s-for-beginners
, and it runs as a Docker container. It works perfectly for a sample application. However, what if you have to manage thousands of containers, and coordinate and schedule them properly? How can you upgrade a service without downtime? How do you keep a service healthy upon unexpected failure? These problems exceed the abilities of a system that simply uses containers alone. What we need is a platform that can orchestrate, as well as manage, our containers.
We have told you that Kubernetes is the solution that we need. Next, we will walk you through a series of exercises regarding how to orchestrate and run containers in Kubernetes using a Kubernetes native approach.
Pod Specification
A straightforward thought is that we wish to see what the equivalent API call or command to run a container in Kubernetes is. As explained in Chapter 1, Introduction...