Why?
My config setup is the following, a free-ish version of GKE autopilot, and a load balancer is my ingress. I want the load balancer to terminate TLS.
How
Doing some web surfing I found this blog post and it’s literally
git clone https://github.com/GoogleCloudPlatform/gke-managed-certs
cd gke-managed-certs
kubectl apply -f managedcertificates-crd.yaml
kubectl apply -f managed-certificates-controller.yaml
then
kubectl annotate ingress [your-ingress-name]
networking.gke.io/managed-certificates=mydomain-certificate
UPDATE GKE autopilot changes
As of May 2021 GKE removed 3rd party admission webhooks, now you will need to use https://cloud.google.com/kubernetes-engine/docs/how-to/managed-certs