How to Solve the Failure to Establish the ISDN Link When the Router Notifies the ISDN-Side Device That No Available B Channel Exists on the Local End?
The router connects to an integrated services digital network (ISDN) through the ISDN-side device. When the router receives a channel identification message from the ISDN-side device and the message contains the option indicating that only the indicated channel is acceptable, if B channel that the ISDN-side device assigns to the router is occupied, the router notifies the ISDN-side device that there is no available B channel on the local end. In this case, the ISDN link fails to be established.
To solve the problem, run the isdn bch-assign command on the router to enable the router to ignore the option indicating that only the indicated channel is acceptable sent from the ISDN-side device.