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    MAC Address Spoofing

    Scheduled Pinned Locked Moved General pfSense Questions
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    • J
      JollyCloudyCheergoose
      last edited by

      When you do the initial pfSense wizard, on the WAN interface, it lets you spoof the MAC address. I have two questions about this:

      Whatever numbers and letters are entered in there, it says "invalid MAC address", even if it's really copied from another device. Should this error be ignored or what would be accepted?
      But it let me proceed with the "invalid MAC"

      How do you view what the current MAC is after the setup wizard is done. Because if you go under Interfaces->WAN, I don't see it. And if I go back to the wizard again, that page is empty.

      J 1 Reply Last reply Reply Quote 0
      • stephenw10S
        stephenw10 Netgate Administrator
        last edited by

        You can see an entered MAC in Interfaces > WAN. It will allow you to enter a MAC there to spoof to if you need it.

        Steve

        J 1 Reply Last reply Reply Quote 0
        • J
          Jarhead @JollyCloudyCheergoose
          last edited by

          @jollycloudycheergoose If it says "invalid", you might be entering it wrong.
          Make sure you follow this:

          Enter a MAC address in the following format: xx:xx:xx:xx:xx:xx or leave blank.

          1 Reply Last reply Reply Quote 0
          • stephenw10S
            stephenw10 Netgate Administrator
            last edited by

            Mmm, I can't replicate that in 22.01 or 22.05 with a valid MAC: 00:11:22:33:44:55

            1 Reply Last reply Reply Quote 1
            • J
              JollyCloudyCheergoose @stephenw10
              last edited by

              @stephenw10 Hey when I go to that
              Interfaces >> WAN

              I don't see MAC address listed. It does have it under the Wizard setup though, but I'm not sure if doing it via there messes up my previous other settings

              1 Reply Last reply Reply Quote 0
              • stephenw10S
                stephenw10 Netgate Administrator
                last edited by

                You don't see this?

                Screenshot from 2022-07-08 13-01-39.png

                J 1 Reply Last reply Reply Quote 0
                • J
                  JollyCloudyCheergoose @stephenw10
                  last edited by

                  @stephenw10 That is correct, I do NOT see that. On WAN below IPv6 is MTU and MSS.

                  Then it goes right into the next section, WITHOUT a MAC address line.

                  1 Reply Last reply Reply Quote 0
                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by

                    What is your WAN interface? If it's a subinterface type, like a VLAN, you need to spoof the MAC on the parent NIC.

                    J 1 Reply Last reply Reply Quote 0
                    • J
                      JollyCloudyCheergoose @stephenw10
                      last edited by

                      @stephenw10 WAN is a PPoE connection to ISP Modem

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                      • stephenw10S
                        stephenw10 Netgate Administrator
                        last edited by

                        Right, then you need to assign/enable the parent interface and spoof the MAC there. You don't have to set an IP on the parent though, you leave it set to 'none'.

                        Steve

                        J 1 Reply Last reply Reply Quote 0
                        • J
                          JollyCloudyCheergoose @stephenw10
                          last edited by

                          @stephenw10 Do you know where I can find documentation on how to do this?

                          If I'm using the pfSense firewall now, does that mean that my ISP already saw my real MAC address and whatever spoof I did in the Setup Wizard failed?

                          1 Reply Last reply Reply Quote 0
                          • stephenw10S
                            stephenw10 Netgate Administrator
                            last edited by

                            I'm not sure that's detailed anywhere specifically. But it is simple as assigning and enabling the parent interface and setting a MAC there.
                            The ISP would be able to see the parent interface MAC address if they are looking for it. But since it's a PPPoE connection they probably don't care.

                            Steve

                            J 1 Reply Last reply Reply Quote 0
                            • J
                              JollyCloudyCheergoose @stephenw10
                              last edited by

                              @stephenw10 I am really struggling to even find the parent interface tab on the pfSense GUI or netgate documentation.

                              J 1 Reply Last reply Reply Quote 0
                              • J
                                Jarhead @JollyCloudyCheergoose
                                last edited by

                                @jollycloudycheergoose Go to interfaces/assignments.
                                On the bottom there's a drop down with any available interfaces. Find yours, then click add.

                                J 1 Reply Last reply Reply Quote 0
                                • J
                                  JollyCloudyCheergoose @Jarhead
                                  last edited by

                                  @jarhead Yes there's the interfaces in the list that I have currently. And I can add one of the other igb ports. If I add this port it is the "parent"? I am confused by the parent concept

                                  J 1 Reply Last reply Reply Quote 0
                                  • J
                                    Jarhead @JollyCloudyCheergoose
                                    last edited by

                                    @jollycloudycheergoose Post a screenshot of your WAN settings and your interface assignments page.

                                    J 1 Reply Last reply Reply Quote 0
                                    • J
                                      JollyCloudyCheergoose @Jarhead
                                      last edited by

                                      @jarhead pf1.png pf2.png

                                      For security purposes, login credentials/passwords are redacted. Thank-you

                                      J 1 Reply Last reply Reply Quote 0
                                      • J
                                        Jarhead @JollyCloudyCheergoose
                                        last edited by Jarhead

                                        @jollycloudycheergoose Click the green Add button. Then reread the previous instructions above.

                                        1 Reply Last reply Reply Quote 0
                                        • stephenw10S
                                          stephenw10 Netgate Administrator
                                          last edited by

                                          To be clear the pppoe0 interface is running on igb0 as shown. So assign and enable igb0 and set the MAC there.

                                          Steve

                                          J 1 Reply Last reply Reply Quote 0
                                          • J
                                            JollyCloudyCheergoose @stephenw10
                                            last edited by JollyCloudyCheergoose

                                            @stephenw10 On this second “Parent“ Interface, I set the IPv4 Configuration to None or DHCP?

                                            I tried using a second router I control as a fake ISP just to test it, by plugging the pfSense’s WAN into my test router.

                                            If the pfSense parent interface is set to DHCP, then it shows up on my test router with the correct MAC! But then the internet doesn’t work when plugged into the Real PpoE ISP.

                                            But if I do the pfSense Parent set to None, then it doesn’t show up on my test router. So how do I know if the PpoE ISP is seeing my bullshit MAC?

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