Routing
One command family per address family. The default gateway is simply the 0.0.0.0/0 route — there is no separate WAN or LAN concept. Egress is derived from the gateway, since a next-hop lives in exactly one connected subnet.
Static routes
Administrative distance decides across sources — connected 0, RADIUS 5, static 10, DHCP 15, BGP 20, OSPF 110 — metric tie-breaks within one distance, and weight sets the ECMP share among equal-distance routes. Adds and deletes apply live on commit: the RIB reconciles without dropping sessions.
ip route add 0.0.0.0/0 gateway 203.0.113.5
ip route add 10.4.4.0/29 10.20.50.1 # bare-gateway shorthand
ipv6 route add ::/0 2001:db8::1
show ip route detail
Recursive resolution
A static route whose gateway is not on a connected subnet resolves recursively through the covering route, flagged r in the RIB. show ip fib exposes both the configured next-hop and the resolved terminal on-link next-hop; they differ exactly when the route is recursive. Recursion via the default route is allowed by default, loop-guarded and capped at eight hops.
Live default-gateway re-point
Changing the live default gateway does not drop sessions: the change stages, and on commit the daemon ARPs the new gateway and swaps forwarding only once it answers.
routing default-gw 203.0.113.9 commit