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    Default deny rule on in-state (TCP:SA) traffic

    Scheduled Pinned Locked Moved Firewalling
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    • A
      Andrew453
      last edited by

      Hi. A strange one. I have "Default deny rule IPv4 (1000000103)" coming up on LAN traffic on the same subnet. It's not out-of-state traffic. I have the default allow LAN to all rule in place, but it's not firing on this traffic. Any ideas what's going on please? In the logs, I'm trying to access 192.168.117.35 from 192.168.117.2. It looks like the Syn is being sent, but the Syn-Ack being blocked.

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      0_1532986422016_Capture2.JPG

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      • DerelictD
        Derelict LAYER 8 Netgate
        last edited by

        Looks like asymmetric routing since the source and destination hosts are likely the same network.

        The firewall should probably not be seeing those replies at all. The incoming connections are probably hitting the web server in via another path.

        With that being the case that reply traffic would be, in fact, out-of-state.

        Chattanooga, Tennessee, USA
        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
        Do Not Chat For Help! NO_WAN_EGRESS(TM)

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        • A
          Andrew453
          last edited by

          Yes, I think that's exactly what's happening. Thank you.

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