Traceroute - Interpreting output

On a Cisco device, whenever you issue the traceroute command, the output that you see looks something like this:

R1#traceroute Type escape sequence to abort. Tracing the route to VRF info: (vrf in name/id, vrf out name/id) 1 0 msec 4 msec 0 msec 2 4 msec 0 msec 0 msec 3 0 msec 0 msec 4 msec

The output you see for each hop indicates a destination IPv4 address, and three values of time in milliseconds.

The IP addresses are those of the intermediate routers in the path to the destination, with the last entry being the destination itself. On Cisco devices, Traceroute sends out three probes, or echo requests by default. The three values of time are the round trip time taken by each of those three probes from the source to each hop, and not from hop to hop. See the Traceroute note for more details.

Sometimes traceroute will respond with an asterisk or with "!H" which have different meanings.