Module 16: Troubleshoot Static and Default Routes

•An interface can fail

•A service provider drops a connection

•Links can become oversaturated

•An administrator may enter a wrong configuration.

Networks fail for a number of reasons:

Network Administrators

are responsible for pinpointing and solving the problem.

Ping

•Verify Layer 3 connectivity to destination.

•Extended pings provide additional options.

traceroute

•Verify path to destination network.

•It uses ICMP echo reply messages to determine the hops to the destination.

show ip route

•Displays the routing table.

•Used to verify route entries for destination IP addresses.

show ip interface brief

•Displays the status of device interfaces.

•Used to verify the operational status and IP address of an interface.

show cpd neighbors

•Displays a list of directly connected Cisco devices.

•Also used to validate Layer 1 and 2 connectivity.