Storage Classes

Installed by default

MetaKube installs Storage Classes by default that are backed by cloud storage and work out of the box:

Cloud Provider	Storage Class name	Provisioner
OpenStack	sys11-ceph	cinder.csi.openstack.org (CSI)	default except in DBL & CBK regions
OpenStack	sys11-quobyte-external-provisioner	cinder.csi.openstack.org (CSI)	default in DBL & CBK regions
AWS	sys11-aws-ebs (default)	ebs.csi.aws.com (CSI)

Changing the default StorageClass

To change which StorageClass is the default, just add the annotation:

kubectl annotate storageclass <storageclass name> storageclass.kubernetes.io/is-default-class=true

MetaKube will automatically remove the annotation from the managed StorageClass.

Warning

You can't change the storage class of an existing PV or migrate to a different volume type directly. However, you can migrate the data to a different cloud volume type and create new PVs. For more information see the Migration guide.

Access Mode RWX (ReadWriteMany)

Warning

MetaKube Core currently does not support RWX volumes.

We are evaluating options that will enable the use of RWX volumes. Follow our roadmap to receive updates.

Use StorageClass

Kubernetes differentiates three options for spec.storageClassName in a PVC (or indirectly in a StatefulSets' spec.persistentVolumeClaimTemplates):

1. null or equivalent: not specifying the field at all

   Kube-apiserver will automatically populate the field with the name of the default StorageClass.

   Note

   We recommend this option if possible, because it allows switching the default StorageClass without recreating a StatefulSet.

2. Name of a specific StorageClass

   Kubernetes will use the CSI driver of the StorageClass to provision a PV according to the PVC.

3. "" (the empty string)

   This option is reserved for "manual" PV provisioning. Kubernetes will not dynamically create a PV and the PVC will be left in status Pending until a matching PV is created.