Pod Security Policy (PSP) ¶
In most clusters today, by default, all resources (e.g. Deployments and ReplicatSets) have permissions to create pods. Kubernetes however provides a more fine-grained authorization policy called Pod Security Policy (PSP).
PSP allows the cluster owner to define the permission of each object, for example creating a pod. If you have PSP enabled on the cluster, and you deploy ingress-nginx, you will need to provide the Deployment with the permissions to create pods.
Before applying any objects, first apply the PSP permissions by running:
kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/master/docs/examples/psp/psp.yaml
Note: PSP permissions must be granted before to the creation of the Deployment and the ReplicaSet.