Kubernetes + own k8s cloud = the server could not find the requested resource

I would like to configure Gitlab CI (from gitlab.com) in order to use one of my servers where I have installed Kubernetes.

When I click “Add existing cluster” button and fill-in the form (API URL https://my-domain:6443/api, token fetched from the kubectl command line tool and the certificate from the server’s /etc/kubernetes/ssl/ folder) it is working fine.

But my issue appears when I try to install Helm Tiller. When I click the install button it stops with the following error:

Kubernetes error: the server could not find the requested resource

The error message isn’t clear at all, that’s why I’m asking here what is going on and what shall I do to solve this and have my tests running in my cluster?

Thank you in advance.

Looking further the Gitlab source code I found that Gitlab is supposed to first create the “gitlab-managed-apps” namespace if it doesn’t exists.

After clicking the “Install” button and got this error, when I look at the namespaces in Kubernetes, there’s none named “gitlab-managed-apps”.

So I guess the issue is a permission issue (RBAC?).

As of now, I found this blog article which says at the end to disable RBAC and then it’s working … but I’km not a big fan of this.

Using RKE I have installed all the available versions of k8s but all are failing with the same error …
So I guess it isn’t a compatibility issue