[nsp] Two Routes to destination - failover

[Kevin Graham]

On Mon, 12 Jul 2004 21:02:37 -0400, Paul Stewart <pauls at nexicom.net> wrote:

> We currently have a remote site that is working fine.  For redundency we would
> like to take a separate physical route to this location using wireless and
> make this new connection the "primary" connection and the existing connection
> a "backup" connection.

route metrics aren't going to work in this case, since I'm guessing
the link state on the router's interface for the wireless connection
won't track the actual availability. A routing protocol is the
easiest, most straightforward option.

What would also work (if you can run 12.3T) is "Reliable Static
Routing Backup Using Object Tracking":

http://www.cisco.com/univercd/cc/td/doc/product/software/ios123/123newft/123limit/123x/123xe/dbackupx.htm

The one big plus to this approach is by using SAA probes, you could
accomodate for things like variable link quality over the wireless
link. The main caveat would be the potential for assymetry, though
even if you couldn't prevent this just make sure you're  aware of the
impications.