Enabling fuse-overlayfs for all workspaces

Prerequisites

The Enabling container access to /dev/fuse for OpenShift older than 4.15 section has been completed. This is not required for OpenShift versions 4.15 and later.
An active kubectl session with administrative permissions to the destination OpenShift cluster. See Overview of kubectl.

Procedure

Create a ConfigMap that mounts the storage.conf file for all user workspaces.

kind: ConfigMap
apiVersion: v1
metadata:
  name: fuse-overlay
  namespace: eclipse-che
  labels:
    app.kubernetes.io/part-of: che.eclipse.org
    app.kubernetes.io/component: workspaces-config
  annotations:
    controller.devfile.io/mount-as: subpath
    controller.devfile.io/mount-path: /home/user/.config/containers/
data:
  storage.conf: |
    [storage]
    driver = "overlay"

    [storage.options.overlay]
    mount_program="/usr/bin/fuse-overlayfs"

Creating this ConfigMap will cause all running workspaces to restart.

Set the necessary annotation in the spec.devEnvironments.workspacesPodAnnotations field of the CheCluster custom resource.
kind: CheCluster apiVersion: org.eclipse.che/v2 spec: devEnvironments: workspacesPodAnnotations: io.kubernetes.cri-o.Devices: /dev/fuse
For OpenShift versions before 4.15, the io.openshift.podman-fuse: "" annotation is also required.

Verification steps

Start a workspace and verify that the storage driver is overlay.

$ podman info | grep overlay

Example output:

graphDriverName: overlay
  overlay.mount_program:
    Executable: /usr/bin/fuse-overlayfs
    Package: fuse-overlayfs-1.12-1.module+el8.9.0+20326+387084d0.x86_64
      fuse-overlayfs: version 1.12
  Backing Filesystem: overlayfs

The following error might occur for existing workspaces:

ERRO[0000] User-selected graph driver "overlay" overwritten by graph driver "vfs" from database - delete libpod local files ("/home/user/.local/share/containers/storage") to resolve.  May prevent use of images created by other tools

In this case, delete the libpod local files as mentioned in the error message.