I have two locations, each with their own individual Internet connection via DSL. They are also connected to one another via wireless WAN. Each location has a Cisco 2841 router with one interface connected to the DSL connection and the other interface connected to the wireless wan. I want to setup a backup Internet route on each router so that if one the locations loses its DSL Internet connection it can automatically route traffic destined for the Internet over the wireless lan and out the other locations DSL connection. I'm pretty sure this is possible, so can anyone assist me with this?
I've attached a simple drawing of the network.