simple question as always..
Danny McPherson
danny at genuity.net
Tue Mar 10 01:33:56 UTC 1998
> could someone explain to me why I can ping but traceroute
> seems to have problem reaching it.
The combination of a firewall (permitting ICMP echo replies/requests, but
filtering your UDP traceroute probes) .. and a traceroute client that doesn't
correctly handle (IMO) the response (ICMP Type 3, Code 13: Communication
Administratively Prohibited).
Many traceroute clients (i.e. ftp://ftp.ee.lbl.gov/traceroute.tar.Z) better
indicate things of this nature:
danny at ice% traceroute auth3.ipass.com
traceroute: Warning: Multiple interfaces found; using 204.74.125.252 @ eb0
traceroute to ren.iPass.COM (167.216.128.232), 30 hops max, 40 byte packets
1 fe0-2.hopper.genuity.net (207.240.3.254) 0.883 ms 0.728 ms 2.731 ms
2 fe11-1.border1.phx1.genuity.net (207.240.103.189) 1.894 ms 13.040 ms
1.377 ms
3 fe-6-0.core1.phx1.genuity.net (207.240.1.1) 1.500 ms 69.045 ms 3.208 ms
4 core1.sjc1.genuity.net (207.240.0.9) 20.429 ms 18.507 ms 18.123 ms
5 207.240.24.178 (207.240.24.178) 20.624 ms 19.139 ms 17.908 ms
6 sanjose1-nbr1.bbnplanet.net (4.0.3.189) 19.179 ms 20.695 ms 20.093 ms
7 su-bfr.bbnplanet.net (4.0.1.1) 20.322 ms 23.264 ms 26.579 ms
8 paloalto-cr8.bbnplanet.net (4.0.2.210) 26.441 ms 41.758 ms 50.069 ms
9 digitisland.bbnplanet.net (131.119.35.82) 84.241 ms 77.681 ms 84.923 ms
10 digitisland.bbnplanet.net (131.119.35.82) 129.785 ms !X * 152.450 ms !X
-danny
> i.e.
> ping -s auth3.ipass.com.
> 64 bytes from holmes.ipass.com (204.198.128.102): icmp_seq=0. time=352. ms
>
> yet traceroute
>
> ...
> 6 s2/2-decker-hi.digisle.net (167.216.156.57) 147 ms 149 ms 148 ms
> 7 s2/2-decker-hi.digisle.net (167.216.156.57) 205 ms * 147 ms
> 8 * s2/2-decker-hi.digisle.net (167.216.156.57) 152 ms *
> 9 s2/2-decker-hi.digisle.net (167.216.156.57) 148 ms * 159 ms
> 10 * s2/2-decker-hi.digisle.net (167.216.156.57) 148 ms *
> 11 s2/2-decker-hi.digisle.net (167.216.156.57) 177 ms * 161 ms
> ...
>
> thnx in adv.
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