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    How to Block DNS Requests from LAN Devices?

    Scheduled Pinned Locked Moved DHCP and DNS
    13 Posts 4 Posters 4.1k Views
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    • pttP
      ptt Rebel Alliance
      last edited by

      Is the pfSense the LAN users DNS ?

      Please post a screenshot of your FW LAN rules

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      • N
        Nonsense
        last edited by

        Yes (if I understand you correctly).  I have not created any rules that were not present in the default settings.

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        • pttP
          ptt Rebel Alliance
          last edited by

          Please post a Screenshot of your LAN Firewall Rules (you can attach the img in "aditional options")

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          • pttP
            ptt Rebel Alliance
            last edited by

            Just create a rule as the ones from the attached screenshot, and "put" above any "pass" rule.

            Is really difficult to help you without knowing (see) your FW rules.

            Block_Ext_DNS.PNG
            Block_Ext_DNS.PNG_thumb

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            • pttP
              ptt Rebel Alliance
              last edited by

              Ok, the rule from my previous post should work, just make sure that it is above the Default allow LAN to any rule

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              • N
                Nonsense
                last edited by

                Thanks–I'll give it a try.

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                • N
                  Nonsense
                  last edited by

                  Oops!  The rule appears to work–with one major problem:  I am assigning fixed IPs to my client computers, so I must specify my pfSense router address in each client--the rule also appears to block this (local LAN) address and, as a result, my clients can't talk to the router!  Is there a way I can make an exception to the rule so it does not block the pfSense router address?

                  :(

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    That rule posted would only block access to tcp/udp 53 that is NOT your pfsense lan address.

                    It would not block access to your pfsense lan address on 53, and then your next default allow rule would allow access to everything that is not based on 53 port

                    You setting static IPs on devices has nothing to do with anything.

                    Post your lan rulesetup up again.  So we can see what you did wrong.

                    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 24.11 | Lab VMs 2.8, 24.11

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                    • N
                      Nonsense
                      last edited by

                      Ah, I tried the setup quickly, early this morning, when I was in a rush.  I retried it again and discovered that I had neglected to configure the "destination" changes in the rule this morning.  It appears to be working now–I'll find out if it still works the next time I reboot pfSense.  Thanks ptt and johnpoz.

                      :)

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                      • Z
                        ZPrime
                        last edited by

                        @Nonsense:

                        Ah, I tried the setup quickly, early this morning, when I was in a rush.  I retried it again and discovered that I had neglected to configure the "destination" changes in the rule this morning.  It appears to be working now–I'll find out if it still works the next time I reboot pfSense.  Thanks ptt and johnpoz.

                        :)

                        Bad network admin.  Fixed/hardcoded IPs on clients are bad juju.  pfSense can do DHCP reservations - use them.  DHCP makes your life much easier.  Why do you want your life to be difficult?  ;D

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