Checking Network Connectivity and Troubleshooting

You can use the ping and traceroute commands to test connectivity to remote devices, and both of them can be used with many protocols, not just IP. But don’t forget that the show ip route command is a good troubleshooting command for verifying your routing table and the show interfaces command will show you the status of each interface.

I’m not going to get into the show interfaces commands here because we’ve already been over that in Chapter 6. But I am going to go over both the debug command and the show processes command you need to troubleshoot a router.

Using the ping Command

So far, you’ve seen many examples of pinging devices to test IP connectivity and name resolution using the DNS server. To see all the different protocols that you can use with the Ping program, type ping ?: