Pod YAML

Every Kubernetes object has four top-level fields: apiVersion, kind, metadata (name, labels) and spec (desired state). A pod's spec is a list of containers:

apiVersion: v1
kind: Pod
metadata:
  name: web
  labels:
    app: web
spec:
  containers:
    - name: nginx
      image: nginx:1.27
      ports:
        - containerPort: 80

containerPort is informational (like EXPOSE in a Dockerfile); it doesn't open traffic.

A container's command can be changed in YAML: command replaces the image's ENTRYPOINT, and args its CMD:

spec:
  containers:
    - name: is
      image: busybox:1.36
      command: ["sh", "-c"]
      args: ["echo merhaba; sleep 3600"]

In YAML, lists are written either with square brackets (["a", "b"]) or with lines each starting with -.