In the past (VyOS 1.1) used a gateway-address configured under the system tree
set system gateway-address <address>), this is no longer supported
and existing configurations are migrated to the new CLI command.
Specify static route into the routing table sending all non local traffic to the nexthop address <address>.
Show routing table entry for the default route.
vyos@vyos:~$ show ip route 0.0.0.0 Routing entry for 0.0.0.0/0 Known via "static", distance 10, metric 0, best Last update 09:46:30 ago * 172.18.201.254, via eth0.201
Configuration of Static