Overview

Finally, we managed to come to the atomic unit in Kubernetes: Pods. But what is a pod ? Well it is simple:

Hypervisors have VM

Docker have Containers

Kuberenets have Pods

You can think of a pod of something between container and a VM. Unlike VM they are mortal, when they die, we just bring a new one, unlike containers though, they have IPs. Generally a pod has a single container in it, but there are exceptions.

Lifecycle

The lifecycle of a pod is the following:

We present a manifest file to the API server

The api server loads the containers, download, install, all that crap and puts it in “pending” state

If it doesn't fail it is put in “Running state”

Again if it doesn't fail it is put in “Succeeded” state

If it fails in any of the previous state, it is put in: “Failed state” and we have to inspect our manifest fail or whatnot. WE DON'T WORK WITH THE FAILED PODS, WE DON'T CARE, THEY ARE DEAD, FINITO :)

Here is a picture for visual reference: