The traceroute command

The traceroute command can be used to trace the exact routing hops and the path that the packets take to the remote destination. The traceroute command uses UDP datagrams and uses the TTL field to trace each hop. Since a router sends an ICMP message when TTL expires in transit, packets are sent with incrementing TTL values so that each hop is traced.

If ICMP unreachables are disabled on an interface along the path, that hop would be shown as a *.

Like the ping command, the traceroute command can also be used in the extended mode. The fields in the extended command are as shown in the following image:

Figure 6: Using ...

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