As I say, I'm no TCP expert, but this sequence is always the last connection that works, and it is hosed after. All other connections end with a different sequence in that FIN,ACK ACK between the server and client. Something about it is not correct, or at least deviates from the norm in such a way as to screw things up. The server starts resending FIN, ACKs a few seconds after the 4 way exchange, and the client ( the LWIP part) ignores them for a while (10 sec or so ) before sending his own FIN, ACKs and the series never seems to get caught up and resolved.
There does seem to be an outstanding bug in 1.3.0 regarding tcp sequence numbers, but I don't know if it is related to this or not. ________________________________________ From: [email protected] [[email protected]] On Behalf Of Kieran Mansley [[email protected]] Sent: Wednesday, April 15, 2009 3:41 AM To: Mailing list for lwIP users Subject: Re: [lwip-users] TCP client side problems using netconn api On Wed, 2009-04-15 at 00:10 -0400, Ben Bobbitt wrote: > In a connection that isn’t going away properly – and results in a > system that I can’t get usable without a reset: > > > > Server FIN, ACK seq 433 ack 70 > > Client ACK seq 70 ack 433 < - note the ack # is == > seq prior > > Client FIN, ACK seq 70 ack 434 > > Server ACK seq 434 ack 71 I'm not sure what your problem is, but it's not the ACKs in the above sequence: the "Client FIN, ACK" acknowledges the "Server FIN, ACK" even though the "Client ACK" on its own didn't. As you're able to get a wireshark capture of the problem I'd be interested to take a look at the pcap. Kieran _______________________________________________ lwip-users mailing list [email protected] http://lists.nongnu.org/mailman/listinfo/lwip-users _______________________________________________ lwip-users mailing list [email protected] http://lists.nongnu.org/mailman/listinfo/lwip-users
