How does a NetworkPolicy in Kubernetes become effective?

How does a NetworkPolicy in Kubernetes become effective?

• A. It becomes effective after it is applied
• B. It becomes effective only after cluster restart
• C. It is effective when resource quotas are updated
• D. It becomes effective after manual approval

Answer: (A)

NetworkPolicy becomes effective as soon as you apply its manifest. When you apply the policy, the API server stores it and a compatible network plugin (the CNI) watches for changes and updates its enforcement rules immediately. There’s no restart, no quota update, and no manual approval required. Remember that the policy will only be enforced if the cluster’s CNI supports NetworkPolicy; otherwise, the policy is ignored.

NetworkPolicy becomes effective as soon as you apply its manifest. When you apply the policy, the API server stores it and a compatible network plugin (the CNI) watches for changes and updates its enforcement rules immediately. There’s no restart, no quota update, and no manual approval required. Remember that the policy will only be enforced if the cluster’s CNI supports NetworkPolicy; otherwise, the policy is ignored.