Trying to Implement Jupyterhub on Kubernetes - docker

Question

I am trying to implement Jupyterhub on a set of 8 unclustered completely identical computers in my school. My instructions were first to cluster the 8 systems (all running Ubuntu 18.04 LTS) and to implement Jupyterhub on that cluster.
After searching the net, these are the instructions that I followed-
Installed docker on both systems using this instructions
(Tried) Implemented a Kubernetes cluster using this instructions and this
Implement Jupyterhub using zero-to-jupyterhub instructions
Using the instructions I managed to do steps 1 and 2 already. But after installing helm using the instructions of zero-to-jupyterhub, I came across the error when doing step 2 of Installing Jupyterhub section in this webpage.
My exact error is:
Error: Get https://10.96.0.1:443/api/v1/namespaces/kube-system/configmaps?labelSelector=NAME%D(MISSING)jhub%!(MISSING)OWNER%D(MISSING)TILLER%!D(MISSING)DEPLOYED: dial tcp 10.96.0.1:443: i/o timeout
Error: UPGRADE FAILED : Get https://10.96.0.1:443/api/v1/namespaces/kube-system/configmaps?labelSelector=NAME%D(MISSING)jhub%!(MISSING)OWNER%D(MISSING)TILLER%!D(MISSING)DEPLOYED: dial tcp 10.96.0.1:443: i/o timeout
then when I view the link I get this: [https://10.96.0.1:443/api/v1/namespaces/...]
{
"kind": "Status",
"apiVersion": "v1",
"metadata": {
},
"status": "Failure",
"message": "configmaps is forbidden: User \"system:anonymous\" cannot list resource \"configmaps\" in API group \"\" in the namespace \"kube-system\"",
"reason": "Forbidden",
"details": {
"kind": "configmaps"
},
"code": 403
}
Has anyone encountered this problem? What did you do?
Thank you for anyone that would answer...
Also, feel free to tell me I'm wrong in the implementation as I am open to new Ideas. If you have any better way to this please leave instructions on how to implement it. Thank you very much.

Answer 1

It looks like you have RBAC enabled and are trying to access the resources that are not permitted to be accessed from your account.
Did you follow the instructions to set up Helm/Tiller? There should be two commands that will create the proper permissions to deploy JupyterHub:
kubectl --namespace kube-system create serviceaccount tiller
kubectl create clusterrolebinding tiller --clusterrole cluster-admin --serviceaccount=kube-system:tiller
Hope this helps!

Answer 2

I had exactly the same issue when I upgraded my minikube. In my case I had to delete the cluster and init it again - everything worked fine from there.
In your case it seems like requests from Tiller are blocked and they can't reach the API. In case of your fresh cluster I think that the issue might be incorrect CNI configuration, but to confirm that you would have to add information on what CNI did you use and if you used --pod-network-cidr= flag or any other steps that could end up with conflict or blocking the Tiller requests.
Before adding that information I can only recommend running:
kubeadm reset
lets assume you want to use Calico:
kubeadm init --pod-network-cidr=192.168.0.0/16
kubectl apply -f https://docs.projectcalico.org/v3.2/getting-started/kubernetes/installation/hosted/rbac-kdd.yaml
kubectl apply -f https://docs.projectcalico.org/v3.2/getting-started/kubernetes/installation/hosted/kubernetes-datastore/calico-networking/1.7/calico.yaml`
Install Helm:
curl https://raw.githubusercontent.com/helm/helm/master/scripts/get > get_helm.sh
chmod 700 get_helm.sh
./get_helm.sh
kubectl create serviceaccount tiller --namespace kube-system
kubectl create clusterrolebinding tiller-cluster-rule \
--clusterrole=cluster-admin \
--serviceaccount=kube-system:tiller
helm init --service-account=tiller
Now follow Jupyter Hub tutorial:
Create the config.yaml as described here.
And install JupyterHub:
helm repo add jupyterhub https://jupyterhub.github.io/helm-chart/
helm repo update
RELEASE=jhub
NAMESPACE=jhub
helm upgrade --install $RELEASE jupyterhub/jupyterhub \
--namespace $NAMESPACE \
--version=0.8.0 \
--values config.yaml