Checking the Interface Continued
To check the statistics for the Serial 0 interface, type:
If the interface and protocol are fully functional, you will see the following information:
- Serial 0 is up, line protocol is up
You may also see the following reply:
- Serial 0 is up, line protocol is down
This is the most common problem condition. The interface is not receiving any network data or keepalive frames, but the interface is up and operational. This is probably a router configuration problem.