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    Introducing Netgate Nexus: Multi-Instance Management at Your Fingertips.

    Disable TCP timestamp

    Scheduled Pinned Locked Moved Firewalling
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    • L Offline
      leapsok
      last edited by

      Hello,

      Is there any way that we can disable the TCP timestamp on Pfsense? I am currently having the dropping or timeout issues from incoming traffic user that behind their proxy server/network.

      Base on the TCPdump result, it might related to the TCP timestamp http://serverfault.com/questions/235965/why-would-a-server-not-send-a-syn-ack-packet-in-response-to-a-syn-packet

      Thanks,
      Leap

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      • johnpozJ Offline
        johnpoz LAYER 8 Global Moderator
        last edited by

        What??  Lets see this wireshark where your not sending synack to your ack.  You know what is more likely for a box to not answer - it didn't get the syn, it has a firewall on, its not even listening on that port.

        So you think pfsense is adding timestamps to packets it forwards.. And that is why your something is not working??  Really??  You do understand the sending OS of the traffic would put the tcp timestamps or not, pfsense is not going to add them to packets it forwards..  Is pfsense the one sending the syn to whatever it is that is not working?

        An intelligent man is sometimes forced to be drunk to spend time with his fools
        If you get confused: Listen to the Music Play
        Please don't Chat/PM me for help, unless mod related
        SG-4860 26.03 | Lab VMs 2.8.1, 26.03

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        • L Offline
          leapsok
          last edited by

          Hello Jonhpoz,

          Thanks for your reply. I am quite new and I would love to hear the answer if problem is not causing by pfsense which easily for me to tell the client who has this problem to look at their settings.

          So you think pfsense is adding timestamps to packets it forwards.. And that is why your something is not working?

          ,
          I am not sure otherwise I won't raise this post in the forum.

          Thanks again.
          Leap

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          • johnpozJ Offline
            johnpoz LAYER 8 Global Moderator
            last edited by

            Not saying the issue is not pfsense, but not really where I would first look..  And I would be betting a large sum of money that it has nothing to do with tcp timestamps that pfsense adding ;)

            Where is this tcpdump?  Taken where - at the server side where the traffic hits and you get no synack back?

            Pfsense is NOT going to be adding tcp timestamps to traffic it forwards that is for sure..

            An intelligent man is sometimes forced to be drunk to spend time with his fools
            If you get confused: Listen to the Music Play
            Please don't Chat/PM me for help, unless mod related
            SG-4860 26.03 | Lab VMs 2.8.1, 26.03

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