Nginx Ingress: service "ingress-nginx-controller-admission" not found

I had the same problem and found a solution from another SO thread.

I had previously installed nginx-ingress using the manifests. I deleted the namespace it created, and the clusterrole and clusterrolebinding as noted in the documentation, but that does not remove the ValidatingWebhookConfiguration that is installed in the manifests, but NOT when using helm by default. As Arghya noted above, it can be enabled using a helm parameter.

Once I deleted the ValidatingWebhookConfiguration, my helm installation went flawlessly.

kubectl delete -A ValidatingWebhookConfiguration ingress-nginx-admission

You can check if there is a validation webhook and a service. If they don't exist double check the deployment and add these.

kubectl get -A ValidatingWebhookConfiguration
NAME                      CREATED AT
ingress-nginx-admission   2020-04-22T15:01:33Z

kubectl get svc -n ingress-nginx
NAME                                 TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)                      AGE
ingress-nginx-controller             NodePort    10.96.212.217   <none>        80:32268/TCP,443:32683/TCP   2m34s
ingress-nginx-controller-admission   ClusterIP   10.96.151.42    <none>        443/TCP                      2m34s

Deployment yamls here have the webhook and service.

Since you have used helm to install it you can enable/disable the webhook via a helm parameter as defined here

There is some issue with SSL cert it seems in the webhook.

Chaning failurePolicy: Fail to Ignore worked for me in the

kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-0.32.0/deploy/static/provider/baremetal/deploy.yaml

for more info check:

https://kubernetes.io/docs/reference/access-authn-authz/extensible-admission-controllers/

my problem is proven to be a ssl cert issue. after I delete"ValidatingWebhookConfiguration", the issue is resolved