kubectl Concepts

What is kubectl?

• Command line tool to interact with the Kubernetes API server.
• Think of it as the "remote control" for your cluster.

Core Objects

• Pod: Smallest deployable unit (runs containers).
• Deployment: Ensures pods are running and handles updates.
• Service: Exposes pods within cluster or externally.
• ConfigMap / Secret: Store configuration and sensitive data.
• Namespace: Logical separation of resources.
• Node: A worker machine.

Declarative vs Imperative

• Imperative: run direct commands (quick changes).
• Declarative: apply YAML files (repeatable & versioned).

Mental Model

Cluster → Node → Pod → Container
Namespace groups → Resources → Controlled via kubectl.