# Require a known ingress class It can be useful to restrict Ingress resources to use a known ingress class that are allowed in the cluster. You can customize this policy to allow ingress classes that are configured in the cluster. ## Policy YAML [known_ingress.yaml](best_practices/known_ingress.yaml) ````yaml apiVersion : kyverno.io/v1alpha1 kind: ClusterPolicy metadata: name: known-ingress annotations: policies.kyverno.io/category: Ingress policies.kyverno.io/description: spec: rules: - name: known-ingress match: resources: kinds: - Ingress validate: message: "Unknown ingress class" pattern: metadata: annotations: kubernetes.io/ingress.class: "F5 | nginx" ````