this is all about setting DHCLIENT_SET_DEFAULT_ROUTE in ifcfg-* file. If there is just one dhcp enabled card no heuristics is needed. If there is more than one, only one has to be choosen. ```release_notes_reachable``` is obsoleted name ... I need to change it to something like ```set_default_route_flag_if_net_reachable``` ... but I need to think of better name ;-)