Storage classes - Amazon EKS

Storage classes

Amazon EKS clusters that were created prior to Kubernetes version 1.11 were not created with any storage classes. You must define storage classes for your cluster to use and you should define a default storage class for your persistent volume claims. For more information, see Storage classes in the Kubernetes documentation.

Note

This topic uses the in-tree Amazon EBS storage provisioner. The existing in-tree Amazon EBS plugin is still supported, but by using a CSI driver, you benefit from the decoupling of Kubernetes upstream release cycle and CSI driver release cycle. Eventually, the in-tree plugin will be discontinued in favor of the CSI driver.

To create an AWS storage class for your Amazon EKS cluster

  1. Determine which storage classes your cluster already has.

    kubectl get storageclass

    Output

    NAME            PROVISIONER             RECLAIMPOLICY   VOLUMEBINDINGMODE      ALLOWVOLUMEEXPANSION   AGE
gp2 (default)   kubernetes.io/aws-ebs   Delete          WaitForFirstConsumer   false                  34m

    If your cluster returns the previous output, then it already has the storage class defined in the remaining steps. You can define other storage classes using the steps for deploying any of the CSI drivers in the Storage chapter. Once deployed, you can set one of the storage classes as your default storage class.

  2. Create an AWS storage class manifest file for your storage class. The gp2-storage-class.yaml example below defines a storage class called gp2 that uses the Amazon EBS gp2 volume type.

    For more information about the options available for AWS storage classes, see AWS EBS in the Kubernetes documentation. 

    kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: gp2
  annotations:
    storageclass.kubernetes.io/is-default-class: "true"
provisioner: kubernetes.io/aws-ebs
parameters:
  type: gp2
  fsType: ext4

  3. Use kubectl to create the storage class from the manifest file. 

    kubectl create -f gp2-storage-class.yaml

    Output:

    storageclass "gp2" created

To define a default storage class

  1. List the existing storage classes for your cluster. A storage class must be defined before you can set it as a default. 

    kubectl get storageclass

    Output:

    NAME      PROVISIONER             AGE
gp2       kubernetes.io/aws-ebs   8m

  2. Choose a storage class and set it as your default by setting the storageclass.kubernetes.io/is-default-class=true annotation. 

    kubectl annotate storageclass gp2 storageclass.kubernetes.io/is-default-class=true

    Output:

    storageclass "gp2" patched

  3. Verify that the storage class is now set as default.

    kubectl get storageclass

    Output:

    gp2 (default)   kubernetes.io/aws-ebs   12m