4.7. Verify device configuration and network connectivity using ping, traceroute, Telnet, SSH, or other utilities
Before we move on to determining IP address problems and how to fix them, I just want to mention some basic DOS commands that you can use to help troubleshoot your network from both a PC and a Cisco router (the commands might do the same thing, but they are implemented differently).
Packet InterNet Groper (ping)
Uses ICMP echo request and replies to test if a node IP stack is initialized and alive on the network.
Displays the list of routers on a path to a network destination by using TTL time-outs and ICMP error messages. This command will not work from a DOS prompt.
Same command as traceroute, but it's a Microsoft ...