Traceroute explanation

Fred Baker fred at cisco.com
Thu Dec 8 15:23:43 CST 2011


This is just a guess, but I'll bet the route changed while you were measuring it.

Traceroute sends a request, awaits a response, sends a request, ... Suppose that the route was

172.28.0.1 -> 10.16.0.2
           -> 41.200.16.1
           -> 172.17.2.25
           -> 213.140.58.10
           -> 195.22.195.125
           -> 4.69.151.13
           -> 213.200.68.61
           -> somewhere else

and after the test got that far, two systems got inserted into the path before level3, resulting in the route entering level3 at a different point, 4.69.141.249. What you now have is

172.28.0.1 -> 10.16.0.2
           -> 41.200.16.1
           -> 172.17.2.25
           -> 213.140.58.10
           -> 195.22.195.125
           -> unknown
           -> unknown
           -> 4.69.141.249
           -> 77.67.66.154
           -> and so on

The effect would be to get a result like this.

Next time you see something like this, suggestion: repeat the traceroute and see what you get.


On Dec 7, 2011, at 12:12 PM, Meftah Tayeb wrote:

> Hey folks,
> i see a strange traceroute there
> 
> Détermination de l'itinéraire vers www.rri.ro [193.231.72.52]
> avec un maximum de 30 sauts :
> 
>  1     2 ms     1 ms     1 ms  172.28.0.1
>  2     1 ms     1 ms     1 ms  localhost [10.16.0.2]
>  3    10 ms    10 ms    13 ms  41.200.16.1
>  4    11 ms    10 ms    11 ms  172.17.2.25
>  5    21 ms    21 ms    21 ms  213.140.58.10
>  6    34 ms    31 ms    55 ms  pos14-0.palermo9.pal.seabone.net [195.22.197.125
> ]
>  7    34 ms    33 ms    35 ms  ae-5-6.bar2.marseille1.level3.net [4.69.151.13]
>  8   106 ms    68 ms    67 ms  xe-1-1-0.mil10.ip4.tinet.net [213.200.68.61]
>  9    74 ms    73 ms    74 ms  ae-1-12.bar1.budapest1.level3.net [4.69.141.249]
> 10    63 ms    63 ms    79 ms  euroweb-gw.ip4.tinet.net [77.67.66.154]
> 11    85 ms    84 ms    84 ms  v15-core1.stsisp.ro [193.151.28.1]
> 12   100 ms   100 ms   102 ms  inet-crli1.qrli1.buh.ew.ro [81.24.28.226]
> 13    81 ms    81 ms    81 ms  193.231.72.10
> 14    92 ms    92 ms    93 ms  ip4-89-238-225-90.euroweb.ro [89.238.225.90]
> 15    89 ms    89 ms    89 ms  webrri.rri.ro.72.231.193.in-addr.arpa [193.231.7
> 2.52]
> Itinéraire déterminé.
> C:\Documents and Settings\TAYEB>
> Seabone, then level3, then Tinet, then level3, then tinet ?
> if is that a routing stufs that i don't know, please let me know :)
> i never saw that befaure
> 
>    Meftah Tayeb
> IT Consulting
> http://www.tmvoip.com/ 
> phone: +21321656139
> Mobile: +213660347746
> 
> 
> __________ Information from ESET NOD32 Antivirus, version of virus signature database 6695 (20111208) __________
> 
> The message was checked by ESET NOD32 Antivirus.
> 
> http://www.eset.com
> 




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