Chapter 7. Requesting persistent storage for workspaces
OpenShift Dev Spaces workspaces and workspace data are ephemeral and are lost when the workspace stops.
To preserve the workspace state in persistent storage while the workspace is stopped, request a Kubernetes PersistentVolume (PV) for the Dev Workspace containers in the OpenShift cluster of your organization’s OpenShift Dev Spaces instance.
You can request a PV by using the devfile or a Kubernetes PersistentVolumeClaim (PVC).
An example of a PV is the /projects/ directory of a workspace, which is mounted by default for non-ephemeral workspaces.
Persistent Volumes come at a cost: attaching a persistent volume slows workspace startup.
Starting another, concurrently running workspace with a ReadWriteOnce PV might fail.
Additional resources
7.1. Requesting persistent storage in a devfile
When a workspace requires its own persistent storage, request a PersistentVolume (PV) in the devfile, and OpenShift Dev Spaces will automatically manage the necessary PersistentVolumeClaims.
Prerequisites
- You have not started the workspace.
Procedure
Add a
volumecomponent in the devfile:... components: ... - name: <chosen_volume_name> volume: size: <requested_volume_size>G ...
Add a
volumeMountfor the relevantcontainerin the devfile:... components: - name: ... container: ... volumeMounts: - name: <chosen_volume_name_from_previous_step> path: <path_where_to_mount_the_PV> ...
Example 7.1. A devfile that provisions a PV for a workspace to a container
When a workspace is started with the following devfile, the cache PV is provisioned to the golang container in the ./cache container path:
schemaVersion: 2.1.0
metadata:
name: mydevfile
components:
- name: golang
container:
image: golang
memoryLimit: 512Mi
mountSources: true
command: ['sleep', 'infinity']
volumeMounts:
- name: cache
path: /.cache
- name: cache
volume:
size: 2Gi7.2. Requesting persistent storage in a PVC
You may opt to apply a PersistentVolumeClaim (PVC) to request a PersistentVolume (PV) for your workspaces in the following cases:
- Not all developers of the project need the PV.
- The PV lifecycle goes beyond the lifecycle of a single workspace.
- The data included in the PV are shared across workspaces.
You can apply a PVC to the Dev Workspace containers even if the workspace is ephemeral and its devfile contains the controller.devfile.io/storage-type: ephemeral attribute.
Prerequisites
- You have not started the workspace.
-
An active
ocsession with administrative permissions to the destination OpenShift cluster. See Getting started with the CLI. -
A PVC is created in your user project to mount to all
Dev Workspacecontainers.
Procedure
Add the
controller.devfile.io/mount-to-devworkspace: truelabel to the PVC.$ oc label persistentvolumeclaim <PVC_name> \ controller.devfile.io/mount-to-devworkspace=trueOptional: Use the annotations to configure how the PVC is mounted:
Table 7.1. Optional annotations Annotation Description controller.devfile.io/mount-path:The mount path for the PVC.
Defaults to
/tmp/<PVC_name>.controller.devfile.io/read-only:Set to
'true'or'false'to specify whether the PVC is to be mounted as read-only.Defaults to
'false', resulting in the PVC mounted as read-write.
Example 7.2. Mounting a read-only PVC
apiVersion: v1 kind: PersistentVolumeClaim metadata: name: <pvc_name> labels: controller.devfile.io/mount-to-devworkspace: 'true' annotations: controller.devfile.io/mount-path: </example/directory> 1 spec: accessModes: - ReadWriteOnce resources: requests: storage: 3Gi 2 volumeName: <pv_name> storageClassName: manual volumeMode: Filesystem
