I have a Kubernetes cluster hosting my own docker registry that I built using the following docs:
https://github.com/kubernetes/kubernetes/tree/master/cluster/addons/registry
and
https://github.com/kubernetes/kubernetes/blob/master/cluster/addons/registry/tls/README.md
When I try to push to the registry I get x509: certificate signed by unknown authority error. I've searched all over and read several github issues and the fix seems to be to install the intermediate cert on the server. Simple right.... Well, the cluster is deployed in GCE using the default cos image. Is there a way install that cert on a minimal container os like cos?
You can use CoreOS toobox for installing stuff on COS based instances.
More resources about debugging COS instances using CoreOS toolbox.
https://cloud.google.com/container-optimized-os/docs/how-to/toolbox