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    Help needed to block extenal DNS requests

    Scheduled Pinned Locked Moved Firewalling
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    • T
      TyMac
      last edited by

      I have a rule set up at the bottom of my LAN tab's stack that is supposed to block all outbound dns traffic on port 53 (screenshot attached) After loading this rule I still seem to be able to resolve DNS on my workstation to external DNS and telnet to 8.8.8.8… etc on port 53.

      What am I doing wrong with this rule?
      block_dns.png
      block_dns.png_thumb

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      • pttP
        ptt Rebel Alliance
        last edited by

        https://doc.pfsense.org/index.php/Firewall_Rule_Processing_Order

        https://doc.pfsense.org/index.php/Example_basic_configuration

        https://doc.pfsense.org/index.php/Blocking_DNS_queries_to_external_resolvers

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        • T
          TyMac
          last edited by

          @ptt:

          https://doc.pfsense.org/index.php/Firewall_Rule_Processing_Order

          https://doc.pfsense.org/index.php/Example_basic_configuration

          https://doc.pfsense.org/index.php/Blocking_DNS_queries_to_external_resolvers

          Yes the rule is exactly the same as your last url:

          https://doc.pfsense.org/index.php/Blocking_DNS_queries_to_external_resolvers

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          • pttP
            ptt Rebel Alliance
            last edited by

            https://doc.pfsense.org/index.php/Firewall_Rule_Processing_Order

            Here you can see how i do (Just note the !LAN)  ;)

            LAN_FW_Rules.png
            LAN_FW_Rules.png_thumb

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            • T
              TyMac
              last edited by

              See attached rule… still not working - either missing something really stupid or something is broke!

              dns2.jpg
              dns2.jpg_thumb

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              • pttP
                ptt Rebel Alliance
                last edited by

                https://doc.pfsense.org/index.php/Firewall_Rule_Troubleshooting

                You need to provide more "details" about your Setup/Network & intended goal (a network diagram will be useful too)

                What is "LAN3_EM0_VLAN….." ?

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                • T
                  TyMac
                  last edited by

                  @ptt:

                  https://doc.pfsense.org/index.php/Firewall_Rule_Troubleshooting

                  You need to provide more "details" about your Setup/Network & intended goal (a network diagram will be useful too)

                  What is "LAN3_EM0_VLAN….." ?

                  There really is not much to diagram - EM0 is the nic that is trunked for the LAN vlans - 753 is this vlan. There are a few vlans on that nic/trunk and a single WAN nic that goes to a modem. That's it. The only goal is to block outbound DNS and use an internal DNS that talks externally over 443. DNS is on the same VLAN as the workstation that can still get to external DNS.

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    Yeah guessing your missing something really stupid - like your clients not going out pfsense as their gateway ;)  Or your putting your rule on interface your client is not using to get to pfsense.. You mention vlans.
                    This is really drop dead simple..

                    So I did a query to 8.8.8.8 via dig, works!  I then put in block rule – doesn't work..  See attached.

                    rulenorule.png
                    rulenorule.png_thumb

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                    • D
                      doktornotor Banned
                      last edited by

                      And clear the states…

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