basic routing question for some

[jeffb]

If i have a router with 1 interface configured for frame relay and the fast ethernet connection with 2 static routes:

192.168.1.0 255.255.255.0 serial1

68.208.56.0 255.255.255.0 serial1

the default route is 0.0.0.0 0.0.0.0 fasthernet0

(syntax may not be 100% correct)

if the frame relay conenction goes down i.e.(serial1)

will a routes be removed until serial1 comes backup?

If i had another device that could except traffic to 68.208.56.0 255.255.255.0 would the router route the traffic based on the default route?

I hope that makes sense? In other words what order would the router process the routing table if the serial1 interface stopped responding.

[tbaranski]

The routes that point out serial1 will be removed when serial1 goes down. All traffic will then follow the default route assuming there aren't any other routes in the routing table.

Note, however, that the serial interface isn't always going to change state to "down" when the Frame connection goes down. It's fairly common to lose connectivity via a Frame interface while the interface is still "up" as far as the router is concerned -- this is just the nature of Frame Relay. However, Frame Relay End-To-End KeepAlives (a fairly new feature in IOS) can help out with this.

[jeffb]

So if the serial1 is not in a down state then the default route will not go into affect. Does it mater whether or not the default route hop is the FA0 or a next hop device?

[tbaranski]

It doesn't matter as far as your original question goes, though I'd suggest making the next-hop a device rather than an interface. If you make it an interface, the router has to ARP for all destinations, and some other device has to answer all these ARPs via proxy-arp, which is ugly.