Change the default StorageClass

This page shows how to change the default Storage Class that is used to provision volumes for PersistentVolumeClaims that have no special requirements.

Before you begin

You need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. If you do not already have a cluster, you can create one by using minikube or you can use one of these Kubernetes playgrounds:

To check the version, enter kubectl version.

Why change the default storage class?

Depending on the installation method, your Kubernetes cluster may be deployed with an existing StorageClass that is marked as default. This default StorageClass is then used to dynamically provision storage for PersistentVolumeClaims that do not require any specific storage class. See PersistentVolumeClaim documentation for details.

The pre-installed default StorageClass may not fit well with your expected workload; for example, it might provision storage that is too expensive. If this is the case, you can either change the default StorageClass or disable it completely to avoid dynamic provisioning of storage.

Deleting the default StorageClass may not work, as it may be re-created automatically by the addon manager running in your cluster. Please consult the docs for your installation for details about addon manager and how to disable individual addons.

Changing the default StorageClass

List the StorageClasses in your cluster:

kubectl get storageclass

The output is similar to this:

NAME                 PROVISIONER               AGE
standard (default)   kubernetes.io/gce-pd      1d
gold                 kubernetes.io/gce-pd      1d

The default StorageClass is marked by (default).

Mark the default StorageClass as non-default:
The default StorageClass has an annotation storageclass.kubernetes.io/is-default-class set to true. Any other value or absence of the annotation is interpreted as false.
To mark a StorageClass as non-default, you need to change its value to false:
```
kubectl patch storageclass standard -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"false"}}}'
```
where standard is the name of your chosen StorageClass.
Mark a StorageClass as default:
Similar to the previous step, you need to add/set the annotation storageclass.kubernetes.io/is-default-class=true.
```
kubectl patch storageclass gold -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}'
```
Please note you can have multiple StorageClass marked as default. If more than one StorageClass is marked as default, a PersistentVolumeClaim without an explicitly defined storageClassName will be created using the most recently created default StorageClass. When a PersistentVolumeClaim is created with a specified volumeName, it remains in a pending state if the static volume's storageClassName does not match the StorageClass on the PersistentVolumeClaim.

Verify that your chosen StorageClass is default:

kubectl get storageclass