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Certified Kubernetes Application Developer CKAD (Kubernetes v1.35 curriculum) · Domain 5: Services and Networking

NetworkPolicy needs a CNI plugin that enforces it (for example Calico or Cilium)

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Last reviewed September 25, 2026 · Leer en español

Kubernetes defines the NetworkPolicy API, but it does not enforce it itself. The API server will happily store any policy you create. Enforcement is the job of the cluster's network plugin, which implements the Container Network Interface (CNI), the standard way Kubernetes asks a plugin to wire up Pod networking. If the plugin does not support NetworkPolicy, your policies exist but have no effect, and all traffic keeps flowing.

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