Kubernetes Patterns — Introduction & Foundational Patterns

The first Kubernetes Patterns episode introduces the second edition and its pattern language. These are not recipes or mandatory settings, but recurring solution shapes for classes of problems. Kubernetes is powerful and complex, so capabilities must be exposed deliberately and constrained where a mistake could affect the cluster.

The core model uses a pod as a composition of containers and declarative resources. Metadata connects objects to labels and annotations: labels drive selection, while annotations carry supporting information. Namespaces offer logical separation and reporting but not complete tenant isolation.

Predictable Demands requires explicit runtime dependencies plus CPU and memory requests and limits. They shape scheduling, QoS, priority, and eviction; bad limits starve the application or leave the cluster uncontrolled. Declarative Deployment adds rollout, rollback, blue-green, and canary strategies around desired state.

Health probes separate startup, readiness, and liveness; a poor check can cause a restart cascade. Managed Lifecycle means handling signals and shutdown, while Automated Placement uses constraints, affinity, and taints. Developers must state resources, dependencies, and lifecycle honestly, leaving fine placement to the platform.