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    DNS Resolver Split outgoing interface

    Scheduled Pinned Locked Moved DHCP and DNS
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    • E
      erasedhammer @johnpoz
      last edited by

      @johnpoz
      I am not sure how its doing, all I know is it IS doing it.

      From pfsense:
      splitdns-interfaces.png

      From upstream router:
      splitdns.png

      As you can see, its sending queries from both.

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      • DerelictD
        Derelict LAYER 8 Netgate @erasedhammer
        last edited by

        @erasedhammer said in DNS Resolver Split outgoing interface:

        Recently I setup up a domain controller which also acts as a DNS server, but I did not want clients using it as the primary dns server,

        Why would one invest in a domain controller but not have their clients use it as the source of information for the domain?

        Genuinely curious.

        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
          The domain override exists for clients to ask the domain controller domain related DNS queries. What I didn't want is the domain controller handling internet DNS queries.

          But to directly answer your question, the domain controller is virtualized on a less than reliable server right now. It isn't that critical right now, nothing important relies on it at this point, just a couple of VDIs.

          johnpozJ 1 Reply Last reply Reply Quote 0
          • 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
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            • E
              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

                  johnpozJ 1 Reply Last reply Reply Quote 0
                  • 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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                      • E
                        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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                          • E
                            erasedhammer @Derelict
                            last edited by

                            @derelict

                            splitdns-resolveroutgoing.png

                            DerelictD 1 Reply Last reply Reply Quote 0
                            • 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)

                              E 1 Reply Last reply Reply Quote 0
                              • 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.

                                DerelictD 1 Reply Last reply Reply Quote 0
                                • 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)

                                    E 1 Reply Last reply Reply Quote 1
                                    • 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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