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    Strange MAC blocking

    Scheduled Pinned Locked Moved General pfSense Questions
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    • B
      brumela
      last edited by

      Hi,

      I have a problem that pfSense is blocking external traftic to WAN interface from one specific MAC address.
      Let me explane …
      I'm trying to connect from external network to WAN interface to port 80. (btw: this port is forwarded to web server in DMZ.).
      I notice that connection is not working just from one MAC address, if I change (macchanger eth0) MAC address, or use different PC, connection is working… I also experiment with different IP addresses on that MAC and none worked, so I'm pretty sure that problem is in MAC address.
      Well I'm pfSense newbie and I wonder ??? if it is possible that pfSense is somehow remembered (learned) my MAC for blocking it?

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      • W
        wallabybob
        last edited by

        @brumela:

        Hi,

        I have a problem that pfSense is blocking external traftic to WAN interface from one specific MAC address.
        Let me explane …
        I'm trying to connect from external network to WAN interface to port 80. (btw: this port is forwarded to web server in DMZ.).
        I notice that connection is not working just from one MAC address

        What does this configuration look like? Do you mean you plug a system directly into the WAN interface of your pfSense? If so, depending on the NICs, you may need a cross over cable rather than a straight through cable. In the case with the allegedly "bad" MAC address, do both ends of the link see it as in the "running" state?

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        • C
          cmb
          last edited by

          It doesn't care about MACs, in regards to filtering. If there's an IP conflict, such as the system has a virtual IP for that IP, that can cause weird behavior such as that. It's also possible, though extremely unlikely, that you somehow have the MAC of that system conflicting with a local MAC on the firewall or elsewhere, by using MAC spoofing inappropriately. Examining a packet capture of that host's traffic should show the issue.

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          • B
            brumela
            last edited by

            What does this configuration look like? Do you mean you plug a system directly into the WAN interface of your pfSense? If so, depending on the NICs, you may need a cross over cable rather than a straight through cable. In the case with the allegedly "bad" MAC address, do both ends of the link see it as in the "running" state?

            No, over switch.

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