ISDN backup from third router

[fisko]

hello!

I have 3 routers A , B and C i have enabled eigrp and all network are accessible.

A and B are in the same ethernet network and B and C are connected over serial interfaces.

How to configure DDR with static floating from A to C?

[sbilgi]

There are several ways to back up a serial connection using ISDN. This method is based on Layer 3 (L3) routing information. A more flexible solution for L3 backup is to use dialer watch.

http://www.cisco.com/en/US/tech/tk713/tk237/technologies_configuration_example09186a00800a3b77.shtml