Setting up Helm

Helm, the package manager for Kubernetes, is a useful tool to install, upgrade and manage applications on a Kubernetes cluster. We will be using Helm to install and manage JupyterHub on our cluster.

Installation

The simplest way to install helm is to run Helm’s installer script at a terminal:

curl https://raw.githubusercontent.com/kubernetes/helm/master/scripts/get | bash

Alternative methods for helm installation exist if you prefer to install without using the script.

Initialization

After installing helm on your machine, initialize helm on your Kubernetes cluster. At the terminal, enter:

  1. Set up a ServiceAccount for use by Tiller, the server side component of helm.

    kubectl --namespace kube-system create serviceaccount tiller
    
  2. Give the ServiceAccount RBAC full permissions to manage the cluser. While most clusters have RBAC enabled and you need this line, you must skip this step if your kubernetes cluster does not have RBAC enabled (for example, if you are using Azure AKS).

    kubectl create clusterrolebinding tiller --clusterrole cluster-admin --serviceaccount=kube-system:tiller
    
  3. Set up Helm on the cluster.

    helm init --service-account tiller
    

This command only needs to run once per Kubernetes cluster.

Verify

You can verify that you have the correct version and that it installed properly by running:

helm version

It should provide output like

Client: &version.Version{SemVer:"v2.4.1", GitCommit:"46d9ea82e2c925186e1fc620a8320ce1314cbb02", GitTreeState:"clean"}
Server: &version.Version{SemVer:"v2.4.1", GitCommit:"46d9ea82e2c925186e1fc620a8320ce1314cbb02", GitTreeState:"clean"}

Make sure you have at least version 2.4.1!

Secure Helm

Ensure that tiller is secure from access inside the cluster:

kubectl --namespace=kube-system patch deployment tiller-deploy --type=json --patch='[{"op": "add", "path": "/spec/template/spec/containers/0/command", "value": ["/tiller", "--listen=localhost:44134"]}]'

Next Step

Congratulations. Helm is now set up. The next step is to install JupyterHub!