I got critical issue since my Metro-e trunk unable to be backup with ISDN. The issue is that, when the Metro-e trunk is down, the ISDN is not triggered since the fastethernet port at router still in UP status, which unable to force the ISDN to trigger automatically. Currently, I m using backup interface method which applied at Fasethernet interface at router like below:
description *** Metro-E Trunk **
ip address 10.35.125.1 255.255.255.0
backup interface dialer1
backup delay 5 60
*comment: Fastethernet1/0 still UP although Metro-E trunk is DOWN.
On design site, the router is connected to fiber-converter which has two ports, one for fiber (metro-e) port and another one is LAN port connecting to the router fastethernet interface.
Is there any methods which can force the ISDN to trigger automatically although the fastethernet status still UP?? Thank you.