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No tcp handshake

0

Hi,

Client said they received " 502 error ". After compare with our wireshark capture we didnt received some client data. But they already transmit as attached screenshot from client. .

  1. Why no tcp handshake ?
  2. What is PSH ACK
  3. How to know the root cause. alt text

asked 20 Feb '17, 23:24

suarez123's gravatar image

suarez123
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accept rate: 0%

edited 20 Feb '17, 23:29

One Answer:

0
  1. It happened before time range demonstrated on your screenshot.
  2. A request for receiving endpoint to transfer data you've sent up the stack immediately without storing it in the buffer. Your first POST request is likely to have it too.
  3. You've not received any packets in reply to your POST. Eventually client gave up with FIN. To answer exactly what's the root cause you have to consider network diagram and probably get server-side capture.

answered 21 Feb '17, 07:03

Packet_vlad's gravatar image

Packet_vlad
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accept rate: 20%

edited 21 Feb '17, 07:12