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ZhangFan's avatar
ZhangFan
Icon for Nimbostratus rankNimbostratus
Nov 07, 2024

TCP Out-of-order, TCP Dup ACK, and TCP Retransmission packets are displayed.

I'd like to ask for advice，The LTM sends a TCP probe to the real server, and TCP Out-of-order, TCP Dup ACK, and TCP Retransmission packets are displayed. And at the same time, the LTM view log shows that the TCP health check to the real server fails: the pool member monitor status down.There was a lot of info soap [11939]:log messages before this issue occurred.

I would like to know how this problem came about and what the solution is？

thank you very much！

 

application delivery
  • ZhangFan's avatar
    ZhangFan
    Icon for Nimbostratus rankNimbostratus
    Nov 07, 2024

    Details are shown in the attachment

  • zamroni777's avatar
    zamroni777
    Icon for Nacreous rankNacreous
    Nov 07, 2024

    if havent, you can try disable ACK on PUSH which is default to Enabled.
    https://my.f5.com/manage/s/article/K29377715#datatransfer

    when enabled, vserver will wait for server response for Acknowledging client's TCP PUSH (which contained client request payload).
    if server response time is slow, clients will do retransmissions.

    you will have to solve the failed monitor separately.
    it is better to consult with application team to set proper health monitor.