Diff. between traceroutes and pings

Unanswered Question
Jan 9th, 2008
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While running a basic ping to data center site, i get full pings not delays,


Ping 192.168.10.10

Reply from 192.168.10.10: bytes=32 time=35ms

Reply from 192.168.10.10: bytes=32 time=35ms


however when i run a traceroute, i get request timeouts but the nexthop, i will get a response time of 35 ms-so it kinda looks like this


1. 192.168.4.5

2. * * * Request time out

3 * * * Request time out

4. 192.168.9.7 35 ms

5 * * * Request time out

6192.168.10.10

could the only reason the be happeing are firewalls?

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Edison Ortiz Wed, 01/09/2008 - 19:46
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Intermediate devices aren't responding to ICMPs either because they are blocking it (Firewalls) or they/or/you don't have a route to you/or/them.


On a traceroute, every transit device will respond back to you with an ICMP while with a ping, only the destination device need to respond.


HTH,


_____


Edison.

guruprasadr Wed, 01/09/2008 - 20:20
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HI,


PING where the request is sent between the source and destination and the response is just seen interms of Reply.


The Devices behind the scenes are hidden in the Output. So only the Destination device Reply the Query.


Int Traceroute, every device has to respond to the ICMP Request in the path to reach the Destination.


Hope this Helps. Do Rate all HELPFUL POSTS


Best Regards,


Guru Prasad R

bvsnarayana03 Wed, 01/09/2008 - 21:40
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In addition to the already mentioned reasons, another instance when RTO is reflected in traceroute is when the intermediate device is unmanaged or dont have IP.

ankbhasi Thu, 01/10/2008 - 02:32
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Hi Narayana,


As you mentioned when the intermediate device does not have an ip or unmanaged it may retuen RTO but is it true that any device which does not have an ip will be considered as a hop by traceroute, I doubt!!


Regards,


Ankur

nygenxny123 Thu, 01/10/2008 - 06:02
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since I am using a VPN tunnel to my destination- I can assume the devices that are not responding are my ISP's?

Edison Ortiz Thu, 01/10/2008 - 06:06
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If you have a VPN, ISP's devices won't be shown in the path. A VPN makes the end-to-end connection look like a directly connected network while having multiple devices in the path.


Since you mentioned VPN, perhaps the hops that aren't replying are the tunnel interfaces from those VPN devices. Often, you don't want to advertise tunnel interfaces into your global routing.


HTH,


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Edison.

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