Kubernetes Workloads: Pod, ReplicaSet, Deployment — Challenge

The goal#

Achieve the same outcome as Kubernetes Workloads: Pod, ReplicaSet, Deployment, from an empty starting point, without the steps.

Ingress, HPA and NetworkPolicy all assume you know what a Pod is and what owns it. This lab builds that, by creating each object and then deleting it to see what the cluster does about it.

Deleting things on purpose is the fastest way to learn what is watching.

What must be true when you are done#

• A Deployment with 3 replicas is running, and you can name the ReplicaSet that owns the Pods.
• Deleting a Pod causes a replacement to appear; deleting the Deployment does not.
• A rolling update keeps the service available, and rollout undo returns to the previous image.
• You can produce a Deployment that creates zero Pods, and explain why.

Rules#

• Do not open the guided lab until you are finished, or until the same problem has held you up for 20 minutes.
• Documentation is allowed. In the job it is the first thing you open.
• Verify every criterion with a command whose output you can read.

If you get stuck#

1. What did you expect, exactly?
2. What happened instead — the error text, not a paraphrase?
3. Which layer is that error from?
4. What is the smallest command that proves the layer below is fine?