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Hi I am trying to filter a packet capture where I can view SYNs not receiving a SYN/ACK back. I am not sure how to accomplish this.

Erik

asked 27 Feb '14, 11:30

protongeek's gravatar image

protongeek
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accept rate: 0%


Assuming the client enters retransmission if it is not receiving a SYN-ACK in time a possible filter would be tcp.analysis.retransmission and tcp.flags.syn==1 - This will not catch the initial SYN packet though.

If it sends a RST after giving up this filter might catch those

 (tcp.flags.reset==1 and tcp.seq==1)

You can combine those with a 'or' of course

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answered 27 Feb '14, 13:06

mrEEde's gravatar image

mrEEde
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accept rate: 20%

edited 27 Feb '14, 13:11

see my answers (and the links therein) to the same question.

http://ask.wireshark.org/questions/10640/how-to-find-syn-not-followed-by-a-synack

Regards
Kurt

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answered 28 Feb '14, 07:31

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Kurt Knochner ♦
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accept rate: 15%

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question asked: 27 Feb '14, 11:30

question was seen: 4,798 times

last updated: 28 Feb '14, 07:31

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