Create Distributed File Storage volumes

This page explains how to create Distributed File Storage volumes on CoreWeave Kubernetes Service (CKS) so that your workloads can share persistent file storage across Pods. It’s intended for cluster operators and application developers who need shared, expandable file storage for CKS workloads. Deploy Distributed File Volumes as Persistent Volumes using Persistent Volume Claims (PVCs). To create a Persistent Volume for a Distributed File Storage volume, configure the PVC with the following settings:

Set the accessMode for the PVC as ReadWriteMany.
Set the storage class as shared-vast.
Set the size to the desired size.
Specify the namespace in the manifest, as PVCs are created and scoped to a namespace.

Cloud Console
kubectl

To create a Distributed File Storage volume in Cloud Console, you need access to an active CKS cluster. If you don’t have any clusters or don’t have access to any clusters, you see the following message:

Cloud Console message shown when no clusters are available

If you have access to an active CKS cluster, navigate to the PVCs page.
Click the Create PVC button at the top right corner of the page.

The Create PVC editor includes both regular text fields and a manifest editor on the right side of the page. You can edit the manifest directly, or use the text fields to configure the PVC. Any changes you make in one are reflected in the other.

Cloud Console Create PVC editor with text fields and manifest editor

Enter the desired name for the PVC in the Name field.
Select the cluster where you want to deploy the PVC in the Cluster field.
Select the namespace for the PVC in the Namespace field.
The Disk Class dropdown may be pre-selected depending on the cluster you selected. If not, select the desired disk class from the dropdown.
Set the size to the desired size in the Size field.
Add labels to the PVC in the Labels field (Optional).
Click Submit.

The following example shows a PVC manifest for deploying a Distributed File Storage volume:

sample-shared-fs.yaml

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: new-pvc
  namespace: default
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 1Gi
  storageClassName: shared-vast

After you create and configure the manifest as desired, apply it using kubectl. For example:

kubectl apply -f sample-shared-fs.yaml

Attach volumes to Pods

After you create your PVC, the next step is to make it available to a workload by attaching it to a Pod.

You must create and provision storage volumes before they can be attached to a Pod.

To attach a Distributed File volume to a Pod, specify the mountPath and name under the volumeMounts stanza. Then, specify the volumes.name and the persistentVolumeClaim.claimName as shown in the following example:

sample-shared-fs-pod.yaml

apiVersion: v1
kind: Pod
metadata:
  name: filesystem-storage-example
spec:
  containers:
  - image: nginx:1.14.2
    name: nginx
    volumeMounts:
    - mountPath: /storage
      name: filesystem-storage
  volumes:
  - name: filesystem-storage
    persistentVolumeClaim:
      claimName: new-pvc

After you create and configure the manifest as desired, apply it using kubectl:

kubectl apply -f sample-shared-fs-pod.yaml

After the Pod is created, verify that the volume is attached by running:

kubectl describe pod filesystem-storage-example

This command shows the volume attached to the Pod in the Volumes section.

Change volume sizes

Storage needs change over time. After a volume is created and deployed, you can expand it or migrate to a smaller volume. You can’t reduce existing volumes in size. To use a smaller volume, create a new, smaller PVC and migrate your data manually.

Expand volumes

You can expand deployed Distributed Filesystem Volumes without disrupting running workloads. After you’ve expanded a volume, you can’t downsize it.

Cloud Console
kubectl

To expand a volume in Cloud Console, open the overflow menu (⋮) for the volume, then click Edit.

Enter the desired size in the Size field, then click Confirm to expand the volume.

To expand a volume using kubectl, use kubectl patch to patch the existing volume manifest. For example, to expand a volume to 500Gi, run the following command. Replace [PVC-NAME] with the name of the PVC to expand.

kubectl patch pvc [PVC-NAME] -p \
  '{"spec":{"resources":{"requests":{"storage": "500Gi"}}}}'

​Attach volumes to Pods

​Change volume sizes

​Expand volumes

Attach volumes to Pods

Change volume sizes

Expand volumes