Large RTT or Why doesn't my ping traffic get discarded?

J. Hellenthal jhellenthal at
Wed Dec 21 21:21:03 UTC 2022

As well if this persists you may consider disabling hardware rx/tx checksumming to see if it clears up your results. Some net cards can get glitchy causing this exact behavior.


 J. Hellenthal

The fact that there's a highway to Hell but only a stairway to Heaven says a lot about anticipated traffic volume.

> On Dec 21, 2022, at 13:58, William Herrin <bill at> wrote:
> On Wed, Dec 21, 2022 at 9:10 AM Jason Iannone <jason.iannone at> wrote:
>> 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?
>> 64 bytes from icmp_seq=398 ttl=54 time=4915.096 ms
>> 64 bytes from icmp_seq=399 ttl=54 time=4310.575 ms
>> 64 bytes from icmp_seq=400 ttl=54 time=4196.075 ms
>> 64 bytes from icmp_seq=401 ttl=54 time=4287.048 ms
>> 64 bytes from icmp_seq=403 ttl=54 time=2280.466 ms
>> 64 bytes from icmp_seq=404 ttl=54 time=1279.348 ms
>> 64 bytes from icmp_seq=405 ttl=54 time=276.669 ms
> Hi Jason,
> This usually means a problem on the Linux machine originating the
> packet. It has lost the ARP for the next hop or something similar so
> the outbound ICMP packet is queued. The glitch repairs itself,
> briefly, releasing the queued packets. Then it comes right back.
> Regards,
> Bill Herrin
> -- 
> For hire.

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