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    Please help me oh mighty gods of pfsense and nat reflection

    Scheduled Pinned Locked Moved NAT
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator @fagoti
      last edited by johnpoz

      @fagoti said in Please help me oh mighty gods of pfsense and nat reflection:

      active directoty /dns - 172.16.100.1
      main local network 172.16.0.0 / 16
      routers 172.16.200.0 / 24

      Ok this problematic - so your lan is 172.16/16 but you have some other router a 172.16.200/24 - that overlaps.. Can you do a drawing.. If you have a downstream router that really should be on a transit, unless this downstream router is doing nat? if that is the case why would it be on some 172.16.200/24 that overlaps your /16?

      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

      F 1 Reply Last reply Reply Quote 1
      • F
        fagoti @johnpoz
        last edited by

        @johnpoz

        thanks for trying to help too john,

        my lan is indeed /16 and the subclass 200.X is reserved to routers
        then , this routers are all 200.x on wan and have dhcp 192.168.x.x for their lan.

        client 192.168.x.x access without problems servers on 172.16.x.x

        but those routers are not using nat of any kind.

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

          @fagoti so its really just 172.16/16 your just putting all your routers on 172.16.200/16 range of IPs

          but those routers are not using nat of any kind.

          That is going to be asymmetrical, if your downstream routers are not doing nat, then that network from your upstream to downstream should be a transit network, no hosts on it..

          If I am understanding yoru setup this is asymmetrical.

          ass.jpg

          either direction ends up with asymmetrical flow, unless you were doing host routing on the clients on your 172.16/16 network

          ass2.jpg

          When you use downstream routers that do not nat, you should be using a transit network.

          pfsense-layer-3-switch.png

          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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          • F
            fagoti @johnpoz
            last edited by

            @johnpoz oh my, you even made diagrams... :) , thanks again, but now it got a little overwhelmed with that many networks and information

            i wont be asking for more until i manage to study this with the same care and fully understand it

            but it seems like a lot of changes for my already huge network.

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

              @fagoti said in Please help me oh mighty gods of pfsense and nat reflection:

              but it seems like a lot of changes for my already huge network.

              Creating a transit is not a lot of work.. But running downstream routers that don't nat are going to cause you all kinds of grief without a transit network.. Or doing host routing on ever host..

              Transit network is the correct solution..

              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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              • F
                fagoti @johnpoz
                last edited by

                im trying to reply but i keep receiving akismet spam message :/

                1 Reply Last reply Reply Quote 0
                • F
                  fagoti @johnpoz
                  last edited by

                  im gonna try breaking my reply in parts

                  1 Reply Last reply Reply Quote 0
                  • F
                    fagoti @johnpoz
                    last edited by

                    @johnpoz

                    It seems you know what you are talking about.
                    I will give it a shot on a smaller scale here.

                    1 Reply Last reply Reply Quote 0
                    • F
                      fagoti @johnpoz
                      last edited by

                      @johnpoz

                      I have just finished doing the "B PLAN" kindly suggested by @viragomann , and its working,

                      its not pretty, and has lots of places to check when it goes bad,.. but works.

                      i will be planning how to change all those links for everyone...

                      but even if i later manage to use your refined transit idea, i can still use those new links i build for split dns, so.. i guess its a good idea to go all the way with it.

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                      • F
                        fagoti @johnpoz
                        last edited by

                        @johnpoz

                        thanks john

                        and by the way @viragomann thanks again, because of your quick tip i ended up improving my understanding of my win.dns features.

                        1 Reply Last reply Reply Quote 0
                        • F
                          fagoti @viragomann
                          last edited by

                          @viragomann i managed to implement a working split dns here. im quite satisfyied.

                          i still want to test @johnpoz advices. (but its crazy here, i have like 50 routers.. i think it would be a mess to go with it)

                          V johnpozJ JonathanLeeJ 3 Replies Last reply Reply Quote 1
                          • V
                            viragomann @fagoti
                            last edited by

                            @fagoti
                            The transit network is needed if devices in the main network 172.16.0.0/16 should be able to communicate with devices in 192.16.0.0/24 behind routers. I didn't consider that this would be desired before.

                            However, if you need this you can simply do that with a VLAN on the same wire. Create a VLAN on pfSense and on the routers, ensure that it doesn't overlap with other subnets, and point a static routes on both routers for the network behind them to the VLAN IP of each other.

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

                              @fagoti said in Please help me oh mighty gods of pfsense and nat reflection:

                              have like 50 routers..

                              Why and the F would you have so many routers.. But ok if you had like 2000 of them you could still put them on a transit network..

                              What are these routers.. Why would you need so many? What are they?

                              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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                              • F
                                fagoti @johnpoz
                                last edited by

                                @johnpoz its a huge network... spread among a number of buildings and neighborhoods.. some of them with 20 or something rooms...

                                and on top of that, lots of different models of routers, more than one ptp optic fiber provider, some vlans, its pretty messy...

                                but its working.

                                and with the split dns i managed to make a little more time on that masterplanning of a better topology :P

                                JonathanLeeJ 1 Reply Last reply Reply Quote 1
                                • JonathanLeeJ
                                  JonathanLee @fagoti
                                  last edited by JonathanLee

                                  @fagoti are you running in a mesh topology setup? You could also test out changes I learned with GNS3 it's a virtual network system. Just set up a virtual test with virtual versions all the routers and items all airgapped for your test. A virtual research test version of your network. GNS3 also lets you load OS onto VMs even add in servers and have it function if needed while testing it. Just double click on the host and it opens. Our cybersecurity Professor showed it off on our last days of class. It's cool. Wicked cool. That reminds I want to play with it tomorrow.

                                  OIP (1).jpeg
                                  (GNS3)

                                  Ref:
                                  https://gns3.com/

                                  I would also start testing out whitebox routers up so I could push down changes to all the routers at once from the control system. also know as SDN (Software Defined Networking).

                                  Make sure to upvote

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                                  • JonathanLeeJ
                                    JonathanLee @fagoti
                                    last edited by JonathanLee

                                    @fagoti you forgot to mention firewalls.

                                    11c7e134f46040f7a9318fcf835bbaa7.jpg

                                    FIREWALLS, lots of firewalls . . .

                                    Make sure to upvote

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                                    • F
                                      fagoti @JonathanLee
                                      last edited by

                                      @JonathanLee we are.

                                      i didnt know that GNS3 system. seems like a great tool. ill be looking into it.
                                      thanks for that great tip

                                      1 Reply Last reply Reply Quote 1
                                      • F
                                        fagoti @JonathanLee
                                        last edited by

                                        @JonathanLee hahahahhahahha lol

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