mdgs/freenas-provisioner

Kubernetes external provisioner using Freenas as backend

What is freenas-provisioner

Freenas-provisioner is a Kubernetes external provisioner. When a PersisitentVolumeClaim appears on a Kube cluster, the provisioner will make the corresponding calls to the configured Freenas API to create a dataset and a NFS share usable by the claim. When the claim or the persistent volume is deleted, the provisioner deletes the previously created dataset and share.

See this for more info on external provisioner : https://github.com/kubernetes-incubator/external-storage

Building

make vendor && make

Binary is located into bin/freenas-provisioner It is compiled to be run on linux-amd64 by default.

Usage

Provision the provisioner

Use the following docker image : docker.io/nmaupu/freenas-provisioner and create a pod with it.

kind: Pod
apiVersion: v1
metadata:
  name: freenas-provisioner
  namespace: kube-system
spec:
  containers:
    - name: freenas-provisioner
      image: docker.io/nmaupu/freenas-provisioner:0.7
      imagePullPolicy: Always
      env:
        - name: IDENTIFIER
          valueFrom:
            fieldRef:
              fieldPath: spec.nodeName
        - name: FREENAS_HOST
          value: 192.168.12.8
        - name: FREENAS_PORT
          value: 443
        - name: FREENAS_USER
          value: root
        - name: FREENAS_PASSWORD
          value: mypass

Use a better secret handling for a real usage. Here is just a small quick test.

Run it on the cluster :

kubectl apply -f pod.yaml

Note : if you cluster run with RBAC support, you need to create according roles for the provisioner to be able to work. You can use the provided rbac.yaml file to do this :

kubectl apply -f rbac.yaml

Example usage

Then we can use our new provisioner. First create a storage class resource which tells what provisioner to use:

---
kind: StorageClass
apiVersion: storage.k8s.io/v1beta1
metadata:
  name: freenas-test-sc
provisioner: maupu.org/freenas

Next, create a persistent volume claim using that storage class :

---
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: freenas-test-pvc
spec:
  storageClassName: freenas-test-sc
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 1Mi

Use that claim on a testing pod :

---
kind: Pod
apiVersion: v1
metadata:
  name: freenas-test-pod
spec:
  containers:
  - name: freenas-test-pod
    image: gcr.io/google_containers/busybox:1.24
    command:
      - "/bin/sh"
    args:
      - "-c"
      - "date >> /mnt/file.log && exit 0 || exit 1"
    volumeMounts:
      - name: freenas-test-volume
        mountPath: "/mnt"
  restartPolicy: "Never"
  volumes:
    - name: freenas-test-volume
      persistentVolumeClaim:
        claimName: freenas-test-pvc

Create everything :

kubectl apply -f usage.yaml

The underlying dataset / NFS share should quickly be poping up on Freenas side. In case of issue, follow the provisioner's logs using :

kubectl -n kube-system logs -f freenas-provisioner