ISDN backup for Fastethernet

[pacafic_croc]

Scenario: I have two routers A and B connected over fastethernet. There is another remote router C. B and C are connected to each other through leased line. A can access C through B. The entire network uses static routes. Is there a mechanism wherein a leased line failure between B and C can initiate an ISDN dialup from A to C.

[Josef Oduwo]

Yes, using Dial-on Demand Routing.

Basically DDR is triggered when traffic that meets a predefined set of criteria is queued to be sent out on a DDR-enabled interface, which would be your B-to-C edge.

Have a looksee here http://www.cisco.com/en/US/products/sw/iosswrel/ps1818/products_configuration_guide_chapter09186a0080087881.html on configuring DDR and particularly here, http://www.cisco.com/warp/public/129/bri-backup-map-watch.html, on using DDR Backup using BRIs and "dialer watch".

Josef.