[Test] check if cephcsi is having any issue to support multiple accessModes.

[Madhu-1]

Kubernetes and the CSI spec support creating a volume with multiple accessModes, check if cephcsi is already supporting it or not and see if there are any issues with the supports, if it's supported and don't have any issues we need to add E2E testing for the same.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in a week if no further activity occurs. Thank you for your contributions.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in a week if no further activity occurs. Thank you for your contributions.

[iPraveenParihar]

Tried with below possible combinations -

• RWO, RWX - ✅
• (ROX, RWX) & (ROX, RWO) & (ROX, RWX, RWO) - ❌ failed to provision volume with StorageClass "rook-ceph-block": rpc error: code = InvalidArgument desc = readOnly accessMode is supported only with content source

we have this check for RWO here -

ceph-csi/internal/util/validate.go

Lines 88 to 99 in d8a0407

	func CheckReadOnlyManyIsSupported(req *csi.CreateVolumeRequest) error {
	for _, capability := range req.GetVolumeCapabilities() {
	if m := capability.GetAccessMode().GetMode(); m == csi.VolumeCapability_AccessMode_MULTI_NODE_READER_ONLY ||
	m == csi.VolumeCapability_AccessMode_SINGLE_NODE_READER_ONLY {
	if req.GetVolumeContentSource() == nil {
	return status.Error(codes.InvalidArgument, "readOnly accessMode is supported only with content source")
	}
	}
	}
	return nil
	}

probably, we need to remove this check or tweak the condition to allow above combination?

[Madhu-1]

ROX is only supported for clone from PVC or clone from snapshot not for a fresh PVC because its empty PVC and of no use for read only mode.

[iPraveenParihar]

ROX is only supported for clone from PVC or clone from snapshot not for a fresh PVC because its empty PVC and of no use for read only mode.

I agree, but now that we aim to support multiple access modes, this condition is no longer relevant. What about a PVC with both ROX and RWO access modes, where one pod writes data while others access it as read-only? 🤔

[Madhu-1]

ROX is only supported for clone from PVC or clone from snapshot not for a fresh PVC because its empty PVC and of no use for read only mode.

I agree, but now that we aim to support multiple access modes, this condition is no longer relevant. What about a PVC with both ROX and RWO access modes, where one pod writes data while others access it as read-only? 🤔

The kubernetes access needs to be translated into CSI specification, AFAIK we don't have such a cap in csi spec, if we have one we need to support it as well.

ROX translates to VolumeCapability_AccessMode_MULTI_NODE_READER_ONLY where its multi node reader only not one writer and many readers. lets dig more and see if we are missing anything and we can add such cases as we need to comply with CSI spec.

[Madhu-1]

https://github.com/kubernetes-csi/csi-lib-utils/blob/master/accessmodes/access_modes.go might help you to translate kube access to CSI spec