Kubernetes Certified Network Administrator Test 2026 – Complete Practice for KCNA Part 2

Open Policy Agent is a policy decision engine used with Kubernetes to enforce governance rules on API requests. Policies are written in Rego and loaded into OPA; when a request reaches the Kubernetes API, OPA evaluates it against these policies and returns a decision (allow or deny). This evaluation flow lets you enforce rules consistently across the cluster, such as requiring specific labels, preventing certain image types, or enforcing resource limits. While OPA stores the policy rules and data, its main role is to evaluate and enforce decisions, not merely to store policies. It’s not for monitoring cluster health, nor for scheduling pods, which are handled by separate tools and components.