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<div class="elementToProof"><span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);">Keep in mind that ping reports
<i>round trip</i> time, so there could be a device delaying the ping reply on the return trip. In these cases, it helps to have a traceroute from both ends, to detect asymmetrical routing and possibly return path congestion invisible in a traceroute from you
end.<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> NANOG <nanog-bounces+mel=beckman.org@nanog.org> on behalf of Mel Beckman <mel@beckman.org><br>
<b>Sent:</b> Wednesday, December 21, 2022 9:22 AM<br>
<b>To:</b> Jason Iannone <jason.iannone@gmail.com>; North American Network Operators' Group <nanog@nanog.org><br>
<b>Subject:</b> Re: Large RTT or Why doesn't my ping traffic get discarded?</font>
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<div class="x_elementToProof"><span class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0); background-color:rgb(255,255,255)">Sometimes this is usually due to high CPU time on the target device. If
the device is under heavy load, the ICMP Echo process gets lowest priority. With a well-known name server like 4.2.2.2, this seems unlikely. It could be an intermediate hop or a routing loop, Do a traceroute to get more detailed per-hop statistics.
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<div class="x_elementToProof"><span style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0); background-color:rgb(255,255,255)"> </span></div>
<div class="x_elementToProof"><span style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0); background-color:rgb(255,255,255)"> -mel<br>
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<div id="x_divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> NANOG <nanog-bounces+mel=beckman.org@nanog.org> on behalf of Jason Iannone <jason.iannone@gmail.com><br>
<b>Sent:</b> Wednesday, December 21, 2022 9:10 AM<br>
<b>To:</b> North American Network Operators' Group <nanog@nanog.org><br>
<b>Subject:</b> Large RTT or Why doesn't my ping traffic get discarded?</font>
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<div>Here's a question I haven't bothered to ask until now. Can someone please help me understand why I receive a ping reply after almost 5 seconds? As I understand it, buffers in SP gear are generally 100ms. According to my math this round trip should have
been discarded around the 1 second mark, even in a long path. Maybe I should buy a lottery ticket. I don't get it. What is happening here?</div>
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<div>Jason<br>
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<div>64 bytes from <a href="http://4.2.2.2">4.2.2.2</a>: icmp_seq=392 ttl=54 time=4834.737 ms</div>
64 bytes from <a href="http://4.2.2.2">4.2.2.2</a>: icmp_seq=393 ttl=54 time=4301.243 ms<br>
64 bytes from <a href="http://4.2.2.2">4.2.2.2</a>: icmp_seq=394 ttl=54 time=3300.328 ms<br>
64 bytes from <a href="http://4.2.2.2">4.2.2.2</a>: icmp_seq=396 ttl=54 time=1289.723 ms<br>
Request timeout for icmp_seq 400<br>
Request timeout for icmp_seq 401<br>
64 bytes from <a href="http://4.2.2.2">4.2.2.2</a>: icmp_seq=398 ttl=54 time=4915.096 ms<br>
64 bytes from <a href="http://4.2.2.2">4.2.2.2</a>: icmp_seq=399 ttl=54 time=4310.575 ms<br>
64 bytes from <a href="http://4.2.2.2">4.2.2.2</a>: icmp_seq=400 ttl=54 time=4196.075 ms<br>
64 bytes from <a href="http://4.2.2.2">4.2.2.2</a>: icmp_seq=401 ttl=54 time=4287.048 ms<br>
64 bytes from <a href="http://4.2.2.2">4.2.2.2</a>: icmp_seq=403 ttl=54 time=2280.466 ms<br>
64 bytes from <a href="http://4.2.2.2">4.2.2.2</a>: icmp_seq=404 ttl=54 time=1279.348 ms<br>
64 bytes from <a href="http://4.2.2.2">4.2.2.2</a>: icmp_seq=405 ttl=54 time=276.669 ms</div>
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