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    DNS Resolver Split outgoing interface

    Scheduled Pinned Locked Moved DHCP and DNS
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator @erasedhammer
      last edited by

      Lets see your gateway and routing table.. The only way pfsense would talk to some gateway from its lan IP, if the gateway is attached to the lan network.

      This is how any router would work. Its not something special to pfsense.

      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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        erasedhammer @johnpoz
        last edited by

        @johnpoz
        Heres the gateway list:
        gateway.png

        I don't have any internet static routes though, so everything gets sent to that default gateway.

        johnpozJ 1 Reply Last reply Reply Quote 0
        • johnpozJ
          johnpoz LAYER 8 Global Moderator @erasedhammer
          last edited by

          But lets see the routing table.. Pfsense shouldn't use the lan IP when it wants to talk to 172.20.0.1

          It shouldn't be able to.. Makes no sense to use that IP when trying to talk to something that is not on that network.

          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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          • E
            erasedhammer @johnpoz
            last edited by

            @johnpoz

            I don't see anything saying to use one of the lan interfaces to go to the internet

            routetable.png

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            • johnpozJ
              johnpoz LAYER 8 Global Moderator @erasedhammer
              last edited by

              Maybe @Derelict has some idea.. I am drawing a blank to how/why it could/would do that..

              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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              • V
                viniciusmerlim
                last edited by

                Have you set the gateway for your server interface? I think you will need to create static routes and set these dns policies in DNS resolver. You will also need to allow this traffic in the rules and put the SERVERS gateway in advanced configuration of these rules for users to use this weird configuration.

                What a tricky scenario.

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                  erasedhammer @viniciusmerlim
                  last edited by

                  @viniciusmerlim

                  What do you mean by gateway for the server interface? It is a gateway in itself.
                  And by static routes, do you mean static routes inside the dns resolver itself? I am unfamiliar with how to do that.

                  Is it a weird configuration? Domain overrides can be used for more than my weird domain controller setup.
                  I think if the domain override could work without selecting additional outgoing interfaces, I wouldn't be seeing this behavior.

                  DerelictD 1 Reply Last reply Reply Quote 0
                  • DerelictD
                    Derelict LAYER 8 Netgate @erasedhammer
                    last edited by

                    @erasedhammer What have you selected as the outgoing interfaces in DNS Resolver/unbound?

                    No, you cannot source a connection for a specific domain from a specific source address. This is something dnsmasq (DNS Forwarder) could do but unbound cannot, unfortunately.

                    Chattanooga, Tennessee, USA
                    A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                    DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                    Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                      erasedhammer @Derelict
                      last edited by

                      @derelict

                      splitdns-resolveroutgoing.png

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                      • DerelictD
                        Derelict LAYER 8 Netgate @erasedhammer
                        last edited by

                        @erasedhammer So it is doing exactly what you told it to do? Source queries from both addresses?

                        Chattanooga, Tennessee, USA
                        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                        Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                        • E
                          erasedhammer @Derelict
                          last edited by

                          @derelict

                          Correct, but the domain override and telling it to use an internal DNS server does not work without selecting the servers interface as outgoing.
                          I guess that is the root of my question, why can't the domain override work without the interface being selected in the outgoing interfaces list.

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                          • DerelictD
                            Derelict LAYER 8 Netgate @erasedhammer
                            last edited by

                            @erasedhammer Because unbound doesn't have that functionality.

                            Chattanooga, Tennessee, USA
                            A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                            DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                            Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                            • DerelictD
                              Derelict LAYER 8 Netgate
                              last edited by

                              @erasedhammer If you set the outgoing interface to All, what happens?

                              That should move the source address selection back to FreeBSD which should select the "closest" interface to the destination address.

                              Chattanooga, Tennessee, USA
                              A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                              DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                              Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                              • E
                                erasedhammer @Derelict
                                last edited by

                                @derelict

                                Seems to be working. Domain override is working and Im not seeing any other interfaces going to the internet.

                                I guess I overthought the implementation, thanks!

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