Use an EFS resource

The Elastic File System (EFS) is the underlying AWS mechanism for providing storage (disk space) to your cluster. A PersistentVolume is a cluster resource that makes EFS storage available to your workloads and ensures that it persists even when no workloads are connected to it. This topic describes how a workload can access a PersistentVolume with a PersistentVolumeClaim.

This page is for Operators and Storage specialists who want to configure and manage storage. To learn more about common roles and example tasks that we reference in Google Cloud content, see Common GKE user roles and tasks .

GKE on AWS supports static provisioning of PersistentVolumes for all supported Kubernetes versions. For clusters at Kubernetes version 1.24 or later, GKE on AWS also supports dynamic provisioning. To use dynamic provisioning, your cluster administrator must configure it. To learn how, see configure a PersistentVolume .

Create a PersistentVolumeClaim

Choose the appropriate tab below depending on whether you want your workload to connect to a statically or dynamically-provisioned persistent volume.

  apiVersion 
 : 
  
 v1 
 kind 
 : 
  
 PersistentVolumeClaim 
 metadata 
 : 
  
 name 
 : 
  
  CLAIM_NAME 
 
 spec 
 : 
  
 accessModes 
 : 
  
 - 
  
 ReadWriteMany 
  
 storageClassName 
 : 
  
 "" 
  
 # Leave as empty string for static provisioning 
  
 resources 
 : 
  
 requests 
 : 
  
 storage 
 : 
  
 5Gi 
 

  apiVersion 
 : 
  
 v1 
 kind 
 : 
  
 PersistentVolumeClaim 
 metadata 
 : 
  
 name 
 : 
  
  CLAIM_NAME 
 
 spec 
 : 
  
 accessModes 
 : 
  
 - 
  
 ReadWriteMany 
  
 storageClassName 
 : 
  
 " EFS_STORAGE_CLASS_NAME 
" 
  
 resources 
 : 
  
 requests 
 : 
  
 storage 
 : 
  
 5Gi 
 

Create a StatefulSet

After you have created a PersistentVolumeClaim, you can use it in a workload. This section creates a sample StatefulSet that uses a PersistentVolumeClaim. You can also use a PersistentVolumeClaim with other workload types such as Pods and Deployments by referencing the claim in spec.volumes .

To create a StatefulSet that mounts the EFS resource referenced in your PersistentVolumeClaim, perform the following steps.

1. Copy the following YAML manifest into a file named efs-statefulset.yaml . This example manifest launches an Ubuntu Linux container that mounts your EFS resource at /efs-data . The container writes every five seconds to a file on your EFS resource named out.txt .

     apiVersion 
    : 
     
    apps/v1 
    kind 
    : 
     
    StatefulSet 
    metadata 
    : 
     
    name 
    : 
     
    efs-shell 
    spec 
    : 
     
    selector 
    : 
     
    matchLabels 
    : 
     
    app 
    : 
     
    test-efs 
     
    serviceName 
    : 
     
    efs-app 
     
    replicas 
    : 
     
    1 
     
    template 
    : 
     
    metadata 
    : 
     
    labels 
    : 
     
    app 
    : 
     
    test-efs 
     
    spec 
    : 
     
    terminationGracePeriodSeconds 
    : 
     
    10 
     
    containers 
    : 
     
    - 
     
    name 
    : 
     
    linux 
     
    image 
    : 
     
    ubuntu:bionic 
     
    command 
    : 
     
    [ 
    "/bin/sh" 
    ] 
     
    args 
    : 
     
    [ 
    "-c" 
    , 
     
    "while 
     
    true; 
     
    do 
     
    echo 
     
    $(date 
     
    -u) 
    >> 
    /efs-data/out.txt; 
     
    sleep 
     
    5; 
     
    done" 
    ] 
     
    volumeMounts 
    : 
     
    - 
     
    name 
    : 
     
    efs-volume 
     
    mountPath 
    : 
     
    /efs-data 
     
    volumes 
    : 
     
    - 
     
    name 
    : 
     
    efs-volume 
     
    persistentVolumeClaim 
    : 
     
    claimName 
    : 
     
     CLAIM_NAME 
    
    
   

   Replace CLAIM_NAME with the name of the PersistentVolumeClaim you specified previously - for example, efs-claim1 .

2. Apply the YAML to your cluster.

      
   kubectl  
   apply  
   -f  
   efs-statefulset.yaml 
   

   The output confirms the StatefulSet's creation.

    statefulset.apps/efs-shell created 
   

   The StatefulSet might take several minutes to download and launch the container image.

3. Confirm the StatefulSet's Pod is in Running status with kubectl get pods .

      
   kubectl  
   get  
   pods  
   -l  
    app 
    = 
   test-efs 
   

   The output includes the name of the Pod and its status. In the following response, the Pod's name is efs-shell-0 .

    NAME          READY   STATUS    RESTARTS   AGE
   efs-shell-0   1/1     Running   0          1m 
   

4. After the Pod is in Running status, use kubectl exec to connect to the Pod hosting the StatefulSet.

      
   kubectl  
    exec 
     
   -it  
   efs-shell-0  
   --  
   bash 
   

   The kubectl command launches a shell on the Pod.

5. To confirm that your EFS resource is mounted, check the contents of the out.txt file with the tail command.

    tail  
   /efs-data/out.txt 
   

   The output contains recent times in UTC.

6. Disconnect from the Pod with the exit command.

      
    exit 
    
   

   Your shell returns to your local machine.

Clean up

To remove the StatefulSet, use kubectl delete .

   
kubectl  
delete  
-f  
efs-statefulset.yaml 

What's next

• Learn how to configure an EFS resource
• Learn how to use StorageClasses with your workloads