Is it possible to create a registry via the cli or in some other way besides using the UI?
If by registry you mean another entry in the app catalog, you can use the REST API (e.g., https://github.com/afgane/ansible-rancher/blob/master/roles/rancher/tasks/main.yml#L225). I don’t know about the CLI.
I was speaking about a docker registry, like dockerhub, quay etc… I dont think there is a way to do so through the cli.
Again, don’t know about the CLI but you can just wrap an API call. If you monitor what’s going on in the dev console in the browser when you add it there, then just replicate it from a shell script.