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fpgasystems / fpga-network-stack

Scalable Network Stack for FPGAs (TCP/IP, RoCEv2)
BSD 3-Clause "New" or "Revised" License
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Linux TCP stack not reacting to SYN packet sent from the FPGA board #26

Closed lastweek closed 3 years ago

lastweek commented 3 years ago

Hi all,

Has anyone tried to build a connection between the board and the Linux kernel TCP stack?

I'm using the board as TCP client, and the Linux as TCP server. I found the Linux is not reacting to the first SYN packet from the board. The board and the server are connected directly with no switch in between.

I suppose I could debug the TCP headers whatnot, but just want to ask whether anyone has the same experience. Thanks.

Here is the SYN packet from tcpdump. The board is 192.168.1.8. The server is 192.168.1.71.

11:37:33.578934 IP (tos 0x0, ttl 64, id 0, offset 0, flags [none], proto TCP (6), length 48)
    192.168.1.8.32768 > 192.168.1.71.60000: Flags [S], cksum 0x32ff (correct), seq 1445134768, win 65535, options [mss 4096,wscale 2,eol], length 0
        0x0000:  0b0a 0908 0706 0605 0403 0201 0800 4500  ..............E.
        0x0010:  0030 0000 0000 4006 f728 c0a8 0108 c0a8  .0....@..(......
        0x0020:  0147 8000 ea60 5623 01b0 0000 0000 7002  .G...`V#......p.
        0x0030:  ffff 32ff 0000 0204 1000 0303 0200       ..2...........
GraceDouX commented 9 months ago

Hi, I want to do TCP iperf benchmarking, is the TCP port number 32768 in this project? Or where to see the TCP port number, if you have any suggestions, appreciated. I tested with TCP port number 32768, but it shows connect failed connection refused