I have ISDN configured on a 1600 with a dialer-group configured to call a 3640 with a 4 port ISDN blade if my frame-relay network goes down. This is the same configuration (with the exception of network address) I um using successfully in other offices. When I try to ping from the ISDN blade in the 1600 to the ISDN blade in the 3640, the pings time out.
Running debug ISDN events, I can see the 1600 dial up and the 3640 connect but the pings will not come back. I have a default route to the frame for each router and a static route to the remote network via the ISDN ip address with an AD of 200 on both routers. On routers that are functioning correctly, I can ping one ISDN blade from the other router and get my replies back - I cannot in this instance. When I compare configs with routers the DO work, they are exactly the same (with the exception of the ip addresses).
Help is greatly appreciated!!