I have a 1720 Router which is connected to a 3600 router vial leased line serial . I have also gone in for a ISDN on both the sides so that it can be configured as Backup.
But the backup does not seem to work.
When the serial goes down , the ISDN says ( spoofing ) and does not connnect to the other site at all.
The commands used are
interface serial 0
backup interface serial 1
backup delay 30 60
Dialer is also configured , but then it does not come up and when we ping the other site ... it gives request timed out.
Thanx ! in advance.