Traceroute Tutorial

Description:

The traceroute application will print the route that packets take in order to arrive at a network host. It works by trying to elicit an ICMP TIME_EXCEEDED response from each gateway along the path to a particular host. For this reason, the times which are actually returned in the traceroute readout are not actually reflective of the times that it requires packets from another protocol such as telnet, SMTP, or FTP to arrive at the destination and gateways along the route.

Usage:

This application is useful for determining whether a host is up and running on the network and/or whether there is a host or gateway along the path that is not passing along packets properly.

Syntax:

The inetroom@cni.org account is simply calling traceroute:

     /usr/local/bin/traceroute <hostname>

Operation on the INETROOM account:

If you select '7' from the main menu, you will be prompted with:

     Trace routing to what host?

Enter a fully qualified domain name (FQDN) and strike RETURN:

     --->  u.washington.edu

Tracing route to u.washington.edu

traceroute to u.washington.edu (140.142.75.1), 30 hops max, 40 byte packets

1 cni-gw (192.100.21.2) 4 ms 4 ms 0 ms

2 wtn5-cni-ck.sura.net (192.221.23.57) 27 ms 27 ms 23 ms

3 128.167.25.9 (128.167.25.9) 27 ms 23 ms 27 ms

4 wtn8-wtn-cf.sura.net (128.167.7.8) 27 ms 27 ms 27 ms

5 sura8-wtn8-c3.sura.net (128.167.212.1) 27 ms 121 ms 215 ms

6 en-0.enss136.t3.nsf.net (192.221.252.248) 27 ms 27 ms 27 ms

7 t3-0.Washington-DC-cnss58.t3.ans.net (140.222.58.1) 27 ms 27 ms 27 ms

8 mf-0.Washington-DC-cnss56.t3.ans.net (140.222.56.222) 27 ms 27 ms 27ms

9 t3-1.Greensboro-cnss72.t3.ans.net (140.222.72.2) 35 ms 35 ms 35 ms

10 t3-0.Atlanta-cnss104.t3.ans.net (140.222.104.1) 43 ms 43 ms 43 ms

11 t3-2.Houston-cnss64.t3.ans.net (140.222.64.3) 70 ms 70 ms 70 ms

12 t3-0.St-Louis-cnss80.t3.ans.net (140.222.80.1) 86 ms 86 ms 86 ms

13 t3-1.Denver-cnss96.t3.ans.net (140.222.96.2) 113 ms 113 ms 113 ms

14 t3-0.Seattle-cnss88.t3.ans.net (140.222.88.1) 121 ms 121 ms 125 ms

15 t3-0.enss143.t3.ans.net (140.222.143.1) 121 ms 125 ms 125 ms

16 uwbr1.cac.washington.edu (192.147.179.12) 125 ms 121 ms 125 ms

17 apex1.cac.washington.edu (140.142.151.177) 125 ms 125 ms 121 ms

18 bissell.cac.washington.edu (140.142.151.138) 137 ms 145 ms 121 ms

19 tolstoy.u.washington.edu (140.142.75.1) 125 ms 121 ms 125 ms

Strike RETURN to continue...

Possible errors:

traceroute: unknown host <hostname>

The host you have tried to trace a routing to could not be located in the domain name system.

* * *

Each gateway is pinged three times. Asterisks designate a host that has not responded within the timeout period. Up to thirty (30) hops are possible, so it is possible that the gateway/host will respond eventually.


craig@cni.org