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    Transparently Intercept and Redirect DNS Traffic to an Internal DNS

    Scheduled Pinned Locked Moved NAT
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    • gnitingG
      gniting @johnpoz
      last edited by

      @johnpoz the NS is on a different subnet...

      johnpozJ 1 Reply Last reply Reply Quote 1
      • M
        Marv21 @gniting
        last edited by Marv21

        @ibbetsion just4fun.jpg

        could you try this just 4 fun?
        Thats mine. So everything will be redirectet from LAN to the SYNAPSELAN (any - directed to to that net or not)

        gnitingG 1 Reply Last reply Reply Quote 0
        • gnitingG
          gniting @Marv21
          last edited by

          @Marv21 said in Transparently Intercept and Redirect DNS Traffic to an Internal DNS:

          @ibbetsion just4fun.jpg

          could you try this just 4 fun?
          Thats mine. So everything will be redirectet from LAN to the SYNAPSELAN (any - directed to to that net or not)

          That caused all DNS resolution to stop working. I think the issue is somewhere else. I am also now finding out that I cannot ping (or ssh) from the 8 Net to anywhere on the 7 Net or anywhere else. But I can go from 7->8 Net. Need to solve that first :)

          M 1 Reply Last reply Reply Quote 0
          • M
            Marv21 @gniting
            last edited by Marv21

            @ibbetsion
            Have you a allow Rule on the 8 net?
            YOu need to allow traffic to 7.

            gnitingG 1 Reply Last reply Reply Quote 0
            • gnitingG
              gniting @Marv21
              last edited by

              @Marv21 said in Transparently Intercept and Redirect DNS Traffic to an Internal DNS:

              @ibbetsion
              Have you a allow Rule on the 8 net?
              YOu need to allow traffic to 7.

              Yes, there is an allow rule on 8.
              392b5001-169f-44b9-96dc-5bdf4f0e4f57-image.png

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

                @ibbetsion said in Transparently Intercept and Redirect DNS Traffic to an Internal DNS:

                the NS is on a different subnet...

                You can not run multiple layer 3 on the same layer 2 and call it a different network..

                For what your seeing to happen, the NS you redirected to had direct access to answer the client..

                . I am also now finding out that I cannot ping (or ssh) from the 8 Net to anywhere on the 7 Net or anywhere else.

                Seems you have bigger issues in your network than just trying to redirect dns..

                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

                gnitingG 1 Reply Last reply Reply Quote 0
                • gnitingG
                  gniting @johnpoz
                  last edited by

                  @johnpoz I was able to resolve the other issues. Everything is on track except for the unexpected source issue.

                  A bit more on the network setup.

                  • ISP modem connected to pfsense on WAN port
                  • pfsense's LAN1 port connected to an unmanaged switch which in turn has all other local devices on it
                  • pfsense's OPT1 port connected directly to host running DNS/pihole

                  LAN1=192.168.7.x network
                  OPT1=192.168.8.x network

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

                    Then what your seeing makes zero sense...

                    So I can for sure duplicate your problem when the NS is on the same network..

                    root@ntp:/home/pi# dig @8.8.8.8 www.google.com
                    ;; reply from unexpected source: 192.168.3.10#53, expected 8.8.8.8#53
                    ;; reply from unexpected source: 192.168.3.10#53, expected 8.8.8.8#53
                    

                    But if I put it on a different subnet works fine, or if forward to loopback, or if setup nat reflect auto outbound nat rules so it

                    natted.jpg

                    You can see from this sniff, pfsense saw traffic to 8.8.8.8, sent it on from its own interface 3.253 to 3.10, got answer and then sent answer back to 3.32 looking like it came from 8.8.8.8

                    natreflec.jpg

                    But yes if client thinks it sending to A, and gets back answer from B - its going to complain.

                    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

                    gnitingG 1 Reply Last reply Reply Quote 0
                    • gnitingG
                      gniting @johnpoz
                      last edited by

                      @johnpoz makes zero sense to me too, hence the continued head-scratching ☺

                      I do have the option enabled to Enable automatic outbound NAT for Reflection. On your network, you have the NAT redirect rule and that's it?

                      M 1 Reply Last reply Reply Quote 0
                      • M
                        Marv21 @gniting
                        last edited by

                        @ibbetsion
                        Both are /24 ?

                        1 Reply Last reply Reply Quote 0
                        • gnitingG
                          gniting
                          last edited by

                          Yes

                          M 1 Reply Last reply Reply Quote 0
                          • M
                            Marv21 @gniting
                            last edited by Marv21

                            @ibbetsion
                            Hmm.
                            What you could try (if you have not done any own modifications in the filesystem) - Backup everything, reinstall Pfsense und roll back the Backup.
                            I had it once a while (4years or greater) that i had done this and suddenly everything was ok.

                            Is this a Virtualized Maschine or something?

                            Could you post all NAT Rules, Outbond Page, Lan Rules and DNSNet rules here as Screenshots?

                            Do you have any Floating Rules?

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

                              @Marv21 said in Transparently Intercept and Redirect DNS Traffic to an Internal DNS:

                              s this a Virtualized Maschine or something?

                              That is a great question...

                              Why don't you just sniff and see exactly what is happening..

                              I don't intercept traffic on the same interface and send back in, but yes that outbound nat automatic should do make it look like i comes from the pfsense interface in that network when you do it that way..

                              If pfsense redirects traffic and doesn't nat it or is not the gateway for the return.. Then yes your client is going to scream at you you - wtf is this I sent to A, why is B sending me a response.

                              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

                              gnitingG 1 Reply Last reply Reply Quote 0
                              • gnitingG
                                gniting @Marv21
                                last edited by

                                @Marv21 said in Transparently Intercept and Redirect DNS Traffic to an Internal DNS:

                                @ibbetsion
                                Hmm.
                                What you could try (if you have not done any own modifications in the filesystem) - Backup everything, reinstall Pfsense und roll back the Backup.
                                I had it once a while (4years or greater) that i had done this and suddenly everything was ok.

                                Is this a Virtualized Maschine or something?

                                Could you post all NAT Rules, Outbond Page, Lan Rules and DNSNet rules here as Screenshots?

                                Do you have any Floating Rules?

                                No floating rules and machine is not virtualized. I will try the reinstall recommendation.

                                1 Reply Last reply Reply Quote 0
                                • gnitingG
                                  gniting @johnpoz
                                  last edited by

                                  @johnpoz will attempt to diagnose using packet capture.

                                  M 1 Reply Last reply Reply Quote 0
                                  • M
                                    Marv21 @gniting
                                    last edited by

                                    @ibbetsion
                                    Something new on this?

                                    1 Reply Last reply Reply Quote 0
                                    • gnitingG
                                      gniting
                                      last edited by

                                      Unfortunately not yet. I am attempting to procure a completely separate host to try this out vs having a host that has two NICs (with each NIC on one of two subnets). Just trying to minimize the variables.

                                      M 1 Reply Last reply Reply Quote 0
                                      • M
                                        Marv21 @gniting
                                        last edited by

                                        @ibbetsion
                                        At the Moment you have only one NIC with two VLANs?

                                        gnitingG 1 Reply Last reply Reply Quote 0
                                        • gnitingG
                                          gniting @Marv21
                                          last edited by

                                          @Marv21 No, there are no vlans. The host has two physical NICs.

                                          1 Reply Last reply Reply Quote 0
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