Kubernetes How to resize a Persistent Volume

Question

I'm trying to run a SQL deployment on kubernetes but the persistent volume I used is already full. I want to expand its storage but don't know how? The claim seems immutable. But I can create a new claim if there was any way I could resize the PV.

Answer 1

It is actually possible to do that in the newer versions of Kuberenetes. I think it started from v1.9 onwards.

Check: https://kubernetes.io/blog/2018/07/12/resizing-persistent-volumes-using-kubernetes/

For your PVC edit the PVC size using:

kubectl edit pvc <PVCname>

Now delete the pods associated with volume. The newly created pods will have access to the expanded storage.

Answer 2

This feature is available in newer versions and is still under experimental stage.

Resizing an in-use PersistentVolumeClaim:

feature state: Kubernetes v1.15 (beta)

In this case, you don’t need to delete and recreate a Pod or deployment that is using an existing PVC. Any in-use PVC automatically becomes available to its Pod as soon as its file system has been expanded. This feature has no effect on PVCs that are not in use by a Pod or deployment. You must create a Pod which uses the PVC before the expansion can complete.

Similar to other volume types - FlexVolume volumes can also be expanded when in-use by a pod.

For more info refer to: https://kubernetes.io/docs/concepts/storage/persistent-volumes/

Answer 3

That issue happened to me when I was working with PostgreSQL. New Kubernetes versions allow to resize your persistent volumes but it is not supported yet but all the cloud providers, assuming you are working with a managed kubernetes.

You can check how I solved it:

https://www.mendrugory.com/post/kubernetes-persistent-volumes/