|
HP TCP/IP Services for OpenVMS
HP TCP/IP Services for OpenVMS Tuning and
Troubleshooting
This
traceroute
command displays the route that packets take to a remote host. In this
example, note that display lines 2 and 3 are identical. This is due to
a bug in the kernel on the second hop system,
lbl-csam.arpa
, that forwards packets with a zero TTL. (This is a bug in the
distributed version of BSD Version 4.3.)
#2 |
localhost> traceroute allspice.lcs.mit.edu
traceroute 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
|
In this example, gateways 12, 14, 15, 16, and 17 either do not send
ICMP "time exceeded" messages or send them with a TTL too
small to reach the local host. Further investigation is required to
determine the cause. For example, by contacting the system
administrators for gateways 14 through 17, you could discover that
these gateways are running the MIT C Gateway code that does not send
"time exceeded" messages.
|