'Detach the volume from instance_name.'

def disconnect_volume(self, connection_info, disk_dev, instance):

    LOG.debug('calling    os-brick    to    detach    iSCSI    Volume')
    try:
        self.connector.disconnect_volume(connection_info['data'], None)
    except os_brick_exception.VolumeDeviceNotFound as exc:
        LOG.warning('Ignoring    VolumeDeviceNotFound:    %s', exc)
        return
    LOG.debug('Disconnected    iSCSI    Volume    %s', disk_dev)
    super(LibvirtISCSIVolumeDriver, self).disconnect_volume(connection_info, disk_dev, instance)
