Kubernetes on k3s can't resolve domains from custom dns server (fritz.box with dnsmasq) I have a dns server running at 192.168.0.19 for custom domains like .fritz.box. Having a single node cluster on k3s, Rancher was installed using a subdomain server2.fritz.box using this command: 

    helm install rancher-latest/rancher \
      --name rancher \
      --namespace cattle-system \
      --set hostname=server2.fritz.box


Rancher itself shows that some services are not avaliable and the logs from cattle say server2.fritz.box is not avaliable. Since Kubernetes has its own dns system, I looked at the documentation and it seems that I need to set my .19 dns server so that Kubernetes knows how to resolve .fritz.box domains. Some questions also have similar problems like https://stackoverflow.com/questions/41448095/kube-dns-does-not-resolve-external-hosts-on-kubeadm-bare-metal-cluster

So I created the following yaml:

# https://github.com/kubernetes/kops/issues/4986
apiVersion: v1
kind: ConfigMap
metadata:
  name: kube-dns
  namespace: kube-system
data:
  stubDomains: |
    {"fritz.box": ["192.168.0.19"]}
  upstreamNameservers: |
    ["192.168.0.19"]


Loaded with kubectl apply -f dns.yml. Now created a busybox test pod:

~$ kubectl exec -it busybox -- ping server2.fritz.box
ping: bad address 'server2.fritz.box'


Why is this not working? 
And what must be done to resolve a custom dns server in Kubernetes?
I believe this is an current bug in k3s that upstream DNS is hardcoded to 1.1.1.1.  this should be resolved shortly https://github.com/rancher/k3s/issues/53