Command Reference Guide

420 ● tracert 3Com Router 5000 Family and Router 6000 Family
Command Reference
Example <3Com> tracert 18.26.0.115
tracert to allspice.lcs.mit.edu (18.26.0.115), 30 hops max
1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
2 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 19 ms 19 ms
3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 19 ms
4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 19 ms 39 ms 39 ms
5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 20 ms 39 ms 39 ms
6 128.32.197.4 (128.32.197.4) 59 ms 119 ms 39 ms
7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 39 ms
8 129.140.70.13 (129.140.70.13) 80 ms 79 ms 99 ms
9 129.140.71.6 (129.140.71.6) 139 ms 139 ms 159 ms
10 129.140.81.7 (129.140.81.7) 199 ms 180 ms 300 ms
11 129.140.72.17 (129.140.72.17) 300 ms 239 ms 239 ms
12 * * *
13 128.121.54.72 (128.121.54.72) 259 ms 499 ms 279 ms
14 * * *
15 * * *
16 * * *
17 * * *
18 ALLSPICE.LCS.MIT.EDU (18.26.0.115) 339 ms 279 ms 279 ms
View This command can be used in the following views:
■ Any view
Description The following sections describe how a tracert operates:
■ Tracert sends a packet with TTL value of 1.
■ The fist hop sends back an ICMP TTL Expired message.
■ Tracert resends the packet with TTL value of 2.
■ The second hop sends back an ICMP TTL Expired message when the packet
arrives.
This process continues until the packet reaches its destination. By doing this, the
source station obtains the source address in every returned ICMP TTL Expired message
to draw the path for the IP packet to reach its destination.
After detecting a fault with the ping command, you can use the tracert
command to locate the problem.
The output of the command tracert includes IP addresses of all the gateways along
the path to the destination. If a gateway times out, asterisks (***) are output.