Nope, it's the outgoing one.
Nothing in static route configuration involves the incoming interface. The route is invoked based only on the destination network. The second ip address, in the first example I gave, is the next-hop to which you want the router to direct traffic that matches the static route. Of course the router must have a route to that next-hop address.
Alternatively, if you don't have a next-hop address, you can specify the outgoing interface, as in
(config)#ip route 10.12.19.0 255.255.255.0 serial0
...which will direct all traffic destinating on the 10.12.19.0/24 subnet out of serial interface 0; such as if there's a simple point-to-point link to the next hop (or destination).
If you use the interface option, the route's administrative distance will be 0, whereas if you use the IP next-hop address option, it will be 1. Administrative distance is used when there are multiple routes available to the same destination; the one with the lowest AD wins. You have the option of configuring an AD between 1 and 255 for your static route.
(config)#ip route 10.12.19.0 255.255.255.0 serial0 150
...assigns an AD of 150 to this route. This is often used as a backup in conjunction with a dynamic routing protocol. Say the router was running RIP, whose AD is 120. It would use our static route, with its 150 AD, only until a better route was made known to the RIP process - wherein the route's AD would be 120. It's called a floating static route and is used a lot on back-up links. A floating static route takes over automatically if the dynamic routing protocol, with its lower AD, loses the primary route.
If you want a particular route to be invoked based on the transiting packet's arrival interface, you could create a route-map, where a "match interface" command would be followed by a "set ip next-hop A.B.C.D"
Other methods might include a borderline blasphemous combination of an extended access-list on the arrival interface and some NAT destination static configs, except I'm getting heartburn thinking about how to make that work.
Hope this helps, please rate the post if it does.
Thanks,
-- stuey
