Kubernetes

Kubernetes schedules and runs containers across a cluster. It handles deployment, scaling, networking, and desired state.

Core ideas

• Control plane — API server, etcd, scheduler, controller manager.
• Worker nodes — kubelet, kube-proxy, and a container runtime.
• Pods — smallest deployable unit; one or more containers.
• Services — stable network access to a set of pods.
• Deployments / ReplicaSets — keep the right number of replicas running.

Common add-ons

• Ingress for HTTP entry, cert-manager for TLS.
• ConfigMaps and Secrets for config and credentials.
• Helm for packaging installs.
• Network policies for pod-to-pod rules.
• Storage providers for persistent volumes.