Chapter Summary Continued
You can verify router connectivity to other systems by using telnet to determine if there is Application layer connectivity.
If you cannot get connectivity at the Application layer, try trace and ping, and check your routing table with the show ip route command to determine if there is a problem with the Network layer.
If checking and correcting Network layer problems does not solve the problem, troubleshoot the specific interface.
You can use the show interfaces command from enable mode to check the configuration of each interface.