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    Can't block DNS request for a specific client

    Scheduled Pinned Locked Moved Firewalling
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    • W
      watts3000
      last edited by

      I need to be able to block DNS for a specific client on my network. I have created an alias for that client however when I try to block DNS request using the alias nothing is blocked. However, if I change the protocol to http or https it gets blocked. So my question is how do I block DNS for a specific client?

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      • D
        doktornotor Banned
        last edited by

        Show the screenshot of the rule.

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        • W
          watts3000
          last edited by

          Check out the link

          http://imgur.com/ObQUNmU

          dns.png
          dns.png_thumb

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          • D
            doktornotor Banned
            last edited by

            That is wrong. Make it TCP/UDP (and flush states after that).

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            • W
              watts3000
              last edited by

              I actually had tcp/udp there before and it still did not work. I even flushed the state table and still nothing. As I stated other protocols work just not dns.

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              • D
                doktornotor Banned
                last edited by

                1/ DNS is TCP/UDP. Pointless discussion.
                2/ If it still does not work AFTER you have flushed all the states, then fix the non-matching alias.

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                • W
                  watts3000
                  last edited by

                  Not following you on non matching alias. I configured a basic alias for example alias name is BOB I than added IP address of the workstation in question 192.168.2.50. As stated this same alias has zero problems with http traffic I just find it weird.

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                  • D
                    doktornotor Banned
                    last edited by

                    That TCP/UDP rule will block DNS just perfectly fine if the queries are coming from the computer itself. It will not block anything at all if they are coming from elsewhere, such as another DNS server on LAN.

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                    • P
                      pfBasic Banned
                      last edited by

                      Is there another rule above it that is already passing DNS traffic?

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                      • W
                        watts3000
                        last edited by

                        doktornotor is correct if I define dns servers for example google dns the rule works. My problem is the dns queries are sent to an internal dns server than that server is configured with forwarders out to opendns.

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                        • D
                          doktornotor Banned
                          last edited by

                          Well, so… If you want to force your DNS to pfSense, the only DNS traffic that should be allowed is from pfSense itself.

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

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