Dynamic Provisioning of PVCs

This document describes how to dynamically provision a volume using Kubernetes and Portworx.

Using Dynamic Provisioning

Using Dynamic Provisioning and Storage Classes you don’t need to create Portworx volumes out of band and they will be created automatically. Using Storage Classes objects an admin can define the different classes of Portworx Volumes that are offered in a cluster. Following are the different parameters that can be used to define a Portworx Storage Class

Provision volumes

Step 1: Create Storage Class.

Create the storageclass:

kubectl create -f examples/volumes/portworx/portworx-sc.yaml

Example:

kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: portworx-sc
provisioner: kubernetes.io/portworx-volume
parameters:
  repl: "1"

Download example

Verifying storage class is created:

kubectl describe storageclass portworx-sc

     Name: 	        	portworx-sc
     IsDefaultClass:	        No
     Annotations:		<none>
     Provisioner:		kubernetes.io/portworx-volume
     Parameters:		repl=1
     No events.

Step 2: Create Persistent Volume Claim.

Creating the persistent volume claim:

kubectl create -f examples/volumes/portworx/portworx-volume-pvcsc.yaml

Example:

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: pvcsc001
  annotations:
    volume.beta.kubernetes.io/storage-class: portworx-sc
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 2Gi

Download example

Verifying persistent volume claim is created:

kubectl describe pvc pvcsc001

Name:	      	pvcsc001
Namespace:      default
StorageClass:   portworx-sc
Status:	      	Bound
Volume:         pvc-e5578707-c626-11e6-baf6-08002729a32b
Labels:	      	<none>
Capacity:	    2Gi
Access Modes:   RWO
No Events.

Persistent Volume is automatically created and is bounded to this pvc.

Verifying persistent volume claim is created:

kubectl describe pv pvc-e5578707-c626-11e6-baf6-08002729a32b

Name: 	      	pvc-e5578707-c626-11e6-baf6-08002729a32b
Labels:        	<none>
StorageClass:  	portworx-sc
Status:	      	Bound
Claim:	      	default/pvcsc001
Reclaim Policy: 	Delete
Access Modes:   	RWO
Capacity:	        2Gi
Message:
Source:
Type:	      	PortworxVolume (a Portworx Persistent Volume resource)
VolumeID:   	374093969022973811
No events.

Step 3: Create Pod which uses Persistent Volume Claim with storage class.

Create the pod:

kubectl create -f examples/volumes/portworx/portworx-volume-pvcscpod.yaml

Example:

apiVersion: v1
kind: Pod
metadata:
  name: pvpod
spec:
  containers:
  - name: test-container
    image: gcr.io/google_containers/test-webserver
    volumeMounts:
    - name: test-volume
      mountPath: /test-portworx-volume
  volumes:
  - name: test-volume
    persistentVolumeClaim:
      claimName: pvcsc001

Download example

Verifying pod is created:

kubectl get pod pvpod

NAME      READY     STATUS    RESTARTS   AGE
pvpod       1/1     Running   0          48m

Delete volumes

For dynamically provisioned volumes using StorageClass and PVC (PersistenVolumeClaim), if a PVC is deleted, the corresponding Portworx volume will also get deleted. This is because Kubernetes, for PVC, creates volumes with a reclaim policy of deletion. So the volumes get deleted on PVC deletion.

To delete the PVC and the volume, you can run kubectl delete -f <pvc_spec_file.yaml>