Tracing an IP Route
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Tracing an IP Route

The traceroute command is used to find the IP route from the local switch to a specified IP
address destination. This command displays the individual hops to the destinations as well as
some timing information. When using the traceroute command, you must enter the name of
the destination as part of the command line.
As an example, we might want to trace the route to “corporate.com.” To do so, we would
enter this command:
traceroute corporate.com
A screen similar to the following displays:
traceroute to corporate.com (198.206.185.7),30 hops max,40 byte packets
1 branch-wan-gw.CORPORATE.COM (198.206.181.252) 16 ms 0 ms 16 ms
2 10.254.1.253 (10.254.1.253) 98 ms 81 ms 98 ms
3 198.206.185.7 (198.206.185.7) 121 ms 81 ms 98 ms
Each number displayed corresponds to an individual hop. The time needed to reach that hop
is shown (in milliseconds) after the hop’s IP address. The time may be followed by one of the
following codes:
!The TTL of the received ICMP message is less than or equal to 1.
!H The host was unreachable.
!N The network was unreachable.
!P The protocol was unreachable.
If the time is replaced by an asterisk (*), no response was received from the host during the
default 3-second timeout period.