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Pods, a little deeper

What is really inside a pod.

Beginner10 min · lesson 6 of 24

In plain terms

A pod is a lunchbox holding one main container (and sometimes a small helper) that share the same little space. It’s the smallest thing Kubernetes hands out — or throws away.

A pod is the smallest thing Kubernetes runs. Usually it holds one container — your app. Sometimes it holds a small helper container beside it. Everything in a pod shares one IP address and can share files, and it is always placed on a single machine together.

pod.yaml

apiVersion: v1
kind: Pod
metadata:
  name: web
  labels: { app: web }        # a sticky note we will use later
spec:
  containers:
    - name: app
      image: nginx:1.25
      ports: [{ containerPort: 80 }]

You will rarely create bare pods like this by hand — the controllers in the next topics do it for you — but it is worth seeing one plain, because every bigger object (Deployment, Job, StatefulSet) is really just a machine for producing pods.

A lone pod does not come back

If you create a pod directly and its machine dies, the pod is gone for good — nothing recreates it. For anything you actually care about, use a Deployment (a couple of topics from here).

Your first podReplicaSets: keeping copies alive