Re: [lwip-users] Spurious retransmission of FIN, ACK and ACK
From:
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Subject:
Re: [lwip-users] Spurious retransmission of FIN, ACK and ACK
Date:
Fri, 6 Oct 2017 20:55:54 +0200
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Adrian Figueroa wrote:
I have implemented a simple TCP server
on lwIP 1.4.1 running on chibiOS (a realtime OS) with the
netconn api on an STM32F746.
It goes like this:
[..]
My TCP client (it is a Matlab PC) connects,
sends some data, and disconnects. The TCP server also closes
the connection on its side and then deletes the netconn
structure.
The problem is that I get spurious ACK and
FIN, ACK in Wireshark.
From lwIP's point of view, there's nothing spurious: the FIN sent by
lwIP is not ACKed by the remote host until after the retransmission.
I can't tell you why, but it seems like a remote side issue.
[..]Find a capture attached.
When sending a pcap, the minimum you could do is make reading the
capture easier for anyone wanting to help: From your capture I can
only guess which side is lwIP.