Unanswered Question
Jul 16th, 2007
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The traceroute performed below takes a long time to execute from the router. Can any body tell me Why? but the out put of the traceroute as you may notice is well within the baselined network RTT limits.

I tried the same on another one of our routers on the network (having the same IOS and router model as above) the traceroute is executed immediately.



Protocol [ip]:

Target IP address:

Source address:

Numeric display [n]:

Timeout in seconds [3]: 1

Probe count [3]:

Minimum Time to Live [1]:

Maximum Time to Live [30]:

Port Number [33434]:

Loose, Strict, Record, Timestamp, Verbose[none]: v

Loose, Strict, Record, Timestamp, Verbose[V]:

Type escape sequence to abort.

Tracing the route to

1 16 msec 16 msec 16 msec

2 52 msec 48 msec 52 msec

3 52 msec 56 msec 52 msec

4 52 msec 52 msec 48 msec



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Overall Rating: 5 (1 ratings)
guruprasadr Mon, 07/16/2007 - 00:22
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Can you please let us know howz your Router System Status & CPU Usage Status.

Pls add the "show tech-support" output / show cpu status output

Best Regards,

Guru Prasad R

Richard Burts Mon, 07/16/2007 - 06:46
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I believe that there is a simple explanation for this behavior. traceroute on a Cisco router will attempt to resolve the name for each IP address of each hop and report both the address and the name of the device. I see in the traceroute output that there are no names reported. I believe that at each hop the router is attempting to resolve the address to a name, is sending a DNS request and is waiting for the request to time out (is not getting any response). I suspect that on the other router where it executes quickly either the router has a valid name server configured or is configured with no ip domain-lookup. I believe that you can fix the response time problem on your router either by configuring it to have a valid name server or by configuring no ip domain-lookup which will tell the router not to attempt to resolve addresses to name.



kevindickerson Tue, 07/17/2007 - 06:05
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As a simplier solution to your problem, when you use the extended traceroute command, when you get to the question "Numeric display [n]: " set this to "y" and the traceroute will not try to resolve the ip address. This will hence quicken up the performance of the traceroute command.




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