This is a Container Storage Interface driver for Hetzner Cloud enabling you to use ReadWriteOnce Volumes within Kubernetes. Please note that this driver requires Kubernetes 1.13 or newer.

1. Create an API token in the Hetzner Cloud Console.

2. Create a secret containing the token:

   # secret.yml
   apiVersion: v1
   kind: Secret
   metadata:
     name: hcloud-csi
     namespace: kube-system
   stringData:
     token: YOURTOKEN
   

   and apply it:

   kubectl apply -f <secret.yml>
   

3. Deploy the CSI driver and wait until everything is up and running:

   Have a look at our Version Matrix to pick the correct deployment file.

   kubectl apply -f https://raw.githubusercontent.com/hetznercloud/csi-driver/v1.5.1/deploy/kubernetes/hcloud-csi.yml
   

4. To verify everything is working, create a persistent volume claim and a pod which uses that volume:

   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
   

   Once the pod is ready, exec a shell and check that your volume is mounted at /data.

   kubectl exec -it my-csi-app -- /bin/sh
   

Root servers can be part of the cluster, but the CSI plugin doesn't work there. Taint the root server as follows to skip that node for the daemonset.

kubectl label nodes <node name> instance.hetzner.cloud/is-root-server=true

We aim to support the latest three versions of Kubernetes. After a new Kubernetes version has been released we will stop supporting the oldest previously supported version. This does not necessarily mean that the CSI driver does not still work with this version. However, it means that we do not test that version anymore. Additionally, we will not fix bugs related only to an unsupported version.

The Hetzner Cloud CSI Driver was tested against the official k8s e2e tests for a specific version. You can run the tests with the following commands. Keep in mind, that these tests run on real cloud servers and will create volumes that will be billed.

Test Server Setup:

1x CPX21 (Ubuntu 18.04)

Requirements: Docker and Go 1.17

1. Configure your environment correctly

   export HCLOUD_TOKEN=<specifiy a project token>
   export K8S_VERSION=1.21.0 # The specific (latest) version is needed here
   export USE_SSH_KEYS=key1,key2 # Name or IDs of your SSH Keys within the Hetzner Cloud, the servers will be accessable with that keys

2. Run the tests

   go test $(go list ./... | grep e2etests) -v -timeout 60m

The tests will now run, this will take a while (~30 min).

If the tests fail, make sure to clean up the project with the Hetzner Cloud Console or the hcloud cli.

MIT license