I know that if I have two WAN connections, I can create two static routes, one with a higher distance metric than the other for WAN failover, but that has it's limitations:
It will only use the second default route if the first default route is withdrawn from the routing table, and that would only happen if the interface changes state.
Is there any way to get more intelligence out of the router, such that it can detect a problem with the link (think ip sla) and fail over without requiring an interface state change?
I'm thinking about this for small office deployments who would have a DSL connection and cable backup or something like that. Both WAN connections would have dynamically assigned IP addresses from the provider, so any sort of dynamic routing protocol would be impossible here.
Anyone have any ideas?