Cisco Systems 1700 manual Troubleshooting Isdn

Chapter 3 Troubleshooting

Troubleshooting ISDN

Because ISDN uses many variables and supports many different configurations, it sometimes can cause problems for the router. This section describes problems related to the ISDN line that might occur.

Two commands are useful when troubleshooting ISDN:

•For routers with an ISDN S/T WAN interface card, enter the clear interface command to terminate any active ISDN calls and to reset the ISDN BRI interface. Do this for each ISDN port installed in the router:

Router# clear interface bri0

Router# clear interface bri1

•For routers with an ISDN U WAN interface card(s), use the clear controller command to terminate any active ISDN calls, to reset the ISDN BRI interface, and to reset the ISDN line between the router and the central office switch. Do this for each ISDN port installed in the router:

Router# clear controller bri0

Router# clear controller bri1

Table 3-4lists troubleshooting methods for ISDN-specific problems that might occur.