Cross ping fail for 7 seconds

asked 2023-04-17 06:57:15 +0000

Hi, I'm investigating a failure in my application that I believe is network related. I have two computers, A & B communicating with each other and with some weeks in between there is a failure in my app. I set up ping in computer A to B and computer B to A and log with Wireshark in both computers. The failure got caught with wireshark and at the same time when the app is failing there is something strange with the ping. In computer A ping is working normal, meaning transmit request & receive reply and reply to B ping. But in compter B I see that there is no reply to ping request and I cannot se A pinging when the failure happens for a 7 second period, which is long enough for my real time app to fail. I checked the sequence numbers in the ping and verified that the requests which B does not get any response to is really answered in A wireshark log, but the reply is missing in B Wireshark. More strangely is perhaps that the replies that A gets from ping is not seen in the B Wireshark log, but there is no miss in sequence number replies in A, the pings are really answered. Where should I look for solutions ?

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Comments

What network equipment is in between computer A & B? Try to be as specific as possible.

Jaap gravatar imageJaap ( 2023-04-17 09:49:52 +0000 )edit

Hi, thanks for the question, None, I have just a a short cross-over cable between the computers. (exchanged and tested). The NIC is forced in both computers so there should be no half duplex error. There are more than one NIC in the computer, but NONE of the other NIC are in same subnetwork.

CNygaard gravatar imageCNygaard ( 2023-04-17 12:42:07 +0000 )edit

Did you capture on those other interfaces too? If not, you should.

Jaap gravatar imageJaap ( 2023-04-17 13:00:12 +0000 )edit