:``gw_src``: Netpoint (within src zone) from which this route starts. Must be an existing host/router.
:``gw_dst``: Netpoint (within dst zone) to which this route leads. Must be an existing host/router.
:``symmetrical``: Whether this route is symmetrical, ie, whether we are defining the route ``dst -> src`` at the same
:``gw_src``: Netpoint (within src zone) from which this route starts. Must be an existing host/router.
:``gw_dst``: Netpoint (within dst zone) to which this route leads. Must be an existing host/router.
:``symmetrical``: Whether this route is symmetrical, ie, whether we are defining the route ``dst -> src`` at the same