Setup k3s on Hetzner with CSI drivers

setup-k3s-on-hetzner.sh

#!/bin/bash

LOCATION=${HCLOUD_LOCATION:-nbg1-dc3}

if [ -z "$HCLOUD_TOKEN" ]; then
  echo "You need to set HCLOUD_TOKEN to an Hetzner API token!";
  exit 1
fi

if [ -z "$SSH_KEY" ]; then
  echo "You need to set SSH_KEY to the name of the ssh key you want to use!";
  exit 1
fi

for bin in hcloud jq; do
  if ! which $bin >/dev/null; then
    echo "Cannot find the $bin binary!"
    exit 1
  fi
done

if ! hcloud ssh-key describe $SSH_KEY > /dev/null; then
  echo "Could not find ssh key $SSH_KEY on hetzner"
  exit 1
fi

if ! hcloud server describe k3s-master > /dev/null; then
  echo "Creating a small (2GB memory) €2.49 master"
  hcloud server create --name k3s-master --image ubuntu-18.04 --type cx11 --ssh-key $SSH_KEY --location $LOCATION
fi

hcloud server ssh k3s-master 'curl -sfL https://get.k3s.io | sh -'

mkdir -p $HOME/.kube

IP=$(hcloud server describe k3s-master -o json | jq -r .public_net.ipv4.ip)

hcloud server ssh k3s-master cat /etc/rancher/k3s/k3s.yaml | perl -pe "s/127.0.0.1/$IP/g" > $HOME/.kube/config-k3s

kubectl apply -f https://raw.githubusercontent.com/kubernetes/csi-api/release-1.13/pkg/crd/manifests/csidriver.yaml
kubectl apply -f https://raw.githubusercontent.com/kubernetes/csi-api/release-1.13/pkg/crd/manifests/csinodeinfo.yaml

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
  name: hcloud-csi
  namespace: kube-system
stringData:
  token: $HCLOUD_TOKEN
EOF

kubectl apply -f https://raw.githubusercontent.com/hetznercloud/csi-driver/master/deploy/kubernetes/hcloud-csi.yml

# Verify that persistent volume claims are working.

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: csi-pvc
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 10Gi
  storageClassName: hcloud-volumes
---
kind: Pod
apiVersion: v1
metadata:
  name: my-csi-app
spec:
  containers:
    - name: my-frontend
      image: busybox
      volumeMounts:
      - mountPath: "/data"
        name: my-csi-volume
      command: [ "sleep", "1000000" ]
  volumes:
    - name: my-csi-volume
      persistentVolumeClaim:
        claimName: csi-pvc
EOF

echo "Waiting for our test-pod called my-csi-app to come up"
sleep 20

# Check that /data looks like a Hetzner volume.
kubectl exec -it my-csi-app -- /bin/sh

kubectl delete pod my-csi-app

echo "# ***************************************************************"
echo "export KUBECONFIG=$HOME/.kube/config-k3s"
echo "# ***************************************************************"