Using traceroute to diagnose network routing issues

How do I use a traceroute to diagnose network routing issues?

The troubleshooting steps in this support article should only be taken by your network administrator when diagnosing network connectivity issues. Please refer to this article for a complete list of troubleshooting steps: 

There is a common utility known as traceroute, or tracert in DOS and Windows. The purpose of this utility is to show you the path your traffic takes when you are attempting to connect to another machine.

If a support agent has requested traceroute information from you, please also provide them with the IP of the location where the trace was performed as well as a full timestamp of when it was performed (provide the date, time and timezone of your location).

Not sure how to find your IP address? Here are several free websites that offer you the ability to find your current IP Address:

You will see a result with some gibberish letters, and then as your final result. The series letters before (as well as the final IP address) may change if you run the command more than once. This is because the (gs) Grid-Service uses multiple web nodes, and you could hit one of several.


Performing a traceroute on Windows

  1. Click on start.
  2. Click in the search box.
  3. Then type cmd (you may need to type command in Windows 95/98/ME).
  4. Once you have your Terminal box open, just type in the following:


  5. You should see a response similar to the following:

    Tracing route to []                                        
    over a maximum of 30 hops:                                                                      
    1    <1 ms    <1 ms    <1 ms                                                   
    2    <1 ms    <1 ms    <1 ms                                               
    3     1 ms    <1 ms     1 ms                                                 
    4     1 ms     5 ms     1 ms                                                       
    5     2 ms     2 ms     3 ms                                                       
    6     5 ms     3 ms     2 ms []
    Trace complete.                                                                                         


Performing a traceroute on Mac

  1. Click on Hard Drive.
  2. Open Applications.
  3. Open Utilities.
  4. Click on Terminal to open the command prompt.
  5. Once you have your Terminal box open, type in the following:


    You should see a response similar to the following:

    traceroute to (, 64 hops max, 40 byte packets            
    1 (  1.000 ms  0.739 ms  0.702 ms                                    
    2 (  0.683 ms  0.385 ms  0.315 ms                             
    3 (  0.791 ms  0.703 ms  0.686 ms                         
    4 (  1.430 ms  1.310 ms  1.063 ms                                    
    5 (  2.652 ms  2.260 ms  5.353 ms                                    
    6 (  3.384 ms  8.001 ms  2.439 ms

If you do not wish to deal with traceroute on your own computer, you may use what is known as a "Looking Glass" server. These are publicly available traceroute servers provided by volunteers as a free service. You may find a list of them at Please keep in mind that these results could be inconsistent with the results from your own location, and thus they can be less useful as they use a different path to the server.


Understanding the traceroute

In the results you will see the comment, "over a maximum of 30 hops or 64." All this means is that the diameter of the Internet is roughly 30 or 64 hops. Therefore, many trace routes will only go that far out in trying to reach a destination.

The first column is the hop number, which is the Time-To-Live (TTL) value set in the packet.

The next three columns contains the round-trip times in milliseconds for an attempt to reach the destination with the TTL value. The last column is the host name (if it was resolved) and IP address of the responding system.

NOTE: Your traceroute will display the same information but the columns may possibly be in a different order.



Something to keep an eye out for is a Timeout. This can indicate you have a network or firewall issue that is preventing you from reaching your server:

Tracing route to []
over a maximum of 30 hops:                          
1    <1 ms    <1 ms    <1 ms       
2    <1 ms    <1 ms    <1 ms   
3        *        *        *  Request Time Out       
4        *        *        *  Request Time Out       
5        *        *        *  Request Time Out       
6        *        *        *  Request Time Out        
Trace complete.                                            

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