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I have this traceroute result, and I am wondering what EXACTLY do the 3 numbers mean at the end of each line? I assume they are ping times, but what exactly is the difference between each number?

 1 (  9.429 ms  9.867 ms  10.095 ms
 2 (  10.075 ms  9.887 ms  10.075 ms
 3 (  28.547 ms  39.649 ms  9.992 ms
 4  0.ae2.BR1.DFW13.ALTER.NET (  10.110 ms  9.298 ms  10.109 ms
 5  * * *
 6 (  *  9.798 ms  10.115 ms
 7 (  10.093 ms  9.374 ms  10.100 ms
 8 (  10.310 ms  11.980 ms  12.480 ms
 9 (  12.458 ms  12.190 ms  12.629 ms
10 ( [open]  12.353 ms  2947.212 ms *
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up vote 10 down vote accepted

RTT is "round-trip time", it's the delay between sending the packet and getting the response; the *s mean that the timeout was reached before getting a response.

Three numbers are provided from three different packets to give you a better sampling of the delay to that host.

share|improve this answer
+1 yes, the results from three packets are provided so that you can spot variation in results. Often troublesome networks won't show up in the results of a single packet. If you're running Linux I really recommend the 'mtr' package for traceroutes. – Coops Jun 21 '11 at 20:51
I second that, just that mtr-tiny might be better as it doesn't depend on X (especially when you need to debug remotely over ssh where there's no GUI available) – Server Horror Jun 21 '11 at 21:52
Thanks to all for clarifying that. I couldn't find an answer to that anywhere. – djangofan Jun 23 '11 at 17:00

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