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packet reassembly failed - not observed in wireshark


I am trying to run netperf between two machines. with UDP_STREAM case.

While running netperf client , I can see "packet reassemblies failed" count incremented to a huge number in netserver using the command "netstat -s".

I run the wireshark during the same time, but CANNOT observe any errors as such. My understanding is, Wireshark should be able to notice these packets as errors and display the same.??

Is that mean, even before wireshark capture these "packet reassemblies failed" packets, they get dropped ??

Please help.

asked 07 Oct '14, 00:20

saro's gravatar image

accept rate: 0%

From the info above I guess that the packets are over UDP. If there is no dissector in Wireshark for the UDP packets there will be no reassembly done as Wireshar only "see" UDP datagrams and have no notion of the content.

(07 Oct '14, 03:29) Anders ♦

Yes, I am talking about UDP only.

(07 Oct '14, 06:41) saro

I have another related question. There is an option called UFO (UDP fragmentation offload). Fragmentation is related to IP layer..Why it is tied to UDP alone? why not TCP also? bit confused here. ( Reason for the question is: I see issue only with UFO ON)

(07 Oct '14, 06:42) saro