mountPrefix := "/var/lib/kubelet/plugins/kubernetes.io/iscsi/iface-default/" + devicePath
	lun := "-lun-0"
	device, prefix, err := extractDeviceAndPrefix(mountPrefix + lun)
	if err != nil || device != (devicePath+lun) || prefix != mountPrefix {
		t.Errorf("extractDeviceAndPrefix: expected %s and %s, got %v %s and %s", devicePath+lun, mountPrefix, err, device, prefix)
	}
}

func TestExtractIface(t *testing.T) {

		return volume.ReconstructedVolume{}, fmt.Errorf("couldn't fetch globalPDPath. failed to obtain volume spec")
	}

	// Obtain iscsi disk configurations from globalPDPath
	device, _, err := extractDeviceAndPrefix(globalPDPath)
	if err != nil {
		return volume.ReconstructedVolume{}, err
	}
	bkpPortal, iqn, err := extractPortalAndIqn(device)
	if err != nil {
		return volume.ReconstructedVolume{}, err
	}

			klog.Errorf("iscsi detach disk: failed to unmount: %s\nError: %v", mntPath, err)
			return err
		}
	}

	// if device is no longer used, see if need to logout the target
	device, _, err := extractDeviceAndPrefix(mntPath)
	if err != nil {
		return err
	}

	var bkpPortal []string
	var volName, iqn, iface, initiatorName string
	found := true

	// load iscsi disk config from json file