How to filter out TCP ACKs?

0	Hi, How is it possible that I filter out (remove) the packets that are only TCP ACKs in a capture? I want to use it in tshark. filter capture-filter packet-capture tcp tshark asked 02 Jun '15, 04:10 aby_mcs 6●1●1●3 accept rate: 0% edited 02 Jun '15, 04:10

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Yes. The filter is "tcp.flags.ack==0". But that will leave you with anything that isn't TCP plus a couple of SYN packets (if at all). Because even data packets will have the ACK flag set.

If you want to remove all packets that contain no data and just acknowledge data coming from the other side, use "tcp and not tcp.len==0", to filter away everything that isn't TCP or has no TCP payload.

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answered 02 Jun '15, 04:21

Jasper ♦♦
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Question tags:

tshark ×832
tcp ×752
filter ×349
capture-filter ×184
packet-capture ×61

question asked: 02 Jun '15, 04:10

question was seen: 31,039 times

last updated: 02 Jun '15, 04:21

How to filter out TCP ACKs?

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You have a trillion packets.

You need to see four of them.

Don't have Wireshark?

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