Persistent volumes can be dynamically provisioned via persistent volume claims (PVC). A PVC requests for a PV of a specific storage class, access mode, and size. If a suitable PV exists in the cluster, it is bound to the claim. If suitable PVs do not exist but can be provisioned, a new volume is created and bound to the claim. Kubernetes uses a PVC to obtain the PV backing it and mounts it to the pod.
- A pod and the persistent volume claim it uses must exist in the same namespace.
To dynamically provision a PV to a pod
- Access the Kubernetes cluster via the dashboard. Click Kubernetes access for instructions.
- On the Kubernetes dashboard, create a storage class, as described in Creating storage classes.
Create a persistent volume claim. To do it, click + Create and specify the following YAML file:
apiVersion: v1 kind: PersistentVolumeClaim metadata: name: mypvc spec: accessModes: - ReadWriteOnce resources: requests: storage: 10Gi storageClassName: mysc
This manifest specifies the persistent volume claim
mypvcthat requests from the storage class
mysca volume of at least 10 GiB that can be mounted in the read/write mode by a single node.
Creation of the PVC triggers dynamic provisioning of a persistent volume that satisfies the claim’s requirements. Kubernetes then binds it to the claim.
Create a pod and specify the PVC as its volume. To do it, click + Create and enter the following YAML file:
apiVersion: v1 kind: Pod metadata: name: nginx spec: containers: - image: nginx imagePullPolicy: IfNotPresent name: nginx ports: - containerPort: 80 protocol: TCP volumeMounts: - mountPath: /var/lib/www/html name: mydisk volumes: - name: mydisk persistentVolumeClaim: claimName: mypvc readOnly: false
This configuration file describes the pod
nginxthat uses the persistent volume claim
mypvc. The persistent volume bound to the claim will be accessible at /var/lib/www/html inside the