Kubernetes Pods

What Is a Pod?

A Pod is the smallest deployable unit in Kubernetes. It wraps one or more tightly related containers that should run together on the same node.

Why Pods Instead of Containers Directly?

Kubernetes needs a scheduling unit that can include more than one cooperating container when necessary. A pod gives Kubernetes that unit.

Examples:

• one app container by itself
• an app container plus a sidecar log shipper
• an app container plus a local proxy

Shared Context Inside a Pod

Containers in the same pod share:

• the same network namespace
• the same pod IP address
• the ability to use shared volumes

That means one container can reach another on localhost inside the same pod.

Pod IPs and Ephemeral Nature

Each pod gets an IP address, but pods are ephemeral. If a pod is replaced, the replacement usually gets a different IP.

That is why higher-level resources such as Services exist. Services give stable access even when individual pod IPs change.

Sub-pages in This Section

When Not to Use Bare Pods

You can create a pod directly, but for most applications you should use a Deployment. Deployments recreate failed pods and manage rolling updates.

Mental Model

Think of a pod as a tiny shared apartment for one or more containers. They can share an address and storage, but they come and go as one unit.