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    Setup pfSense behind a ISP router that cannot be put into bridge mode (Double NAT)

    Scheduled Pinned Locked Moved NAT
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    • R
      riahc8 @johnpoz
      last edited by riahc8

      First, thank you all for the help

      I also have to disable the firewall on the ISP router

      johnpozJ 1 Reply Last reply Reply Quote 0
      • johnpozJ
        johnpoz LAYER 8 Global Moderator @riahc8
        last edited by

        @riahc8 Is that a question or a statement?

        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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        • R
          riahc8 @johnpoz
          last edited by

          @johnpoz said in Setup pfSense behind a ISP router that cannot be put into bridge mode (Double NAT):

          @riahc8 Is that a question or a statement?

          That would be a statement. This way I allow all traffic to the pfSense and from there....handle it

          When setting this up, I can still have devices connected to the original ISP router correct?

          johnpozJ 1 Reply Last reply Reply Quote 0
          • johnpozJ
            johnpoz LAYER 8 Global Moderator @riahc8
            last edited by

            @riahc8 For port forwarding, yeah isp routers call that dmz host, etc.. where it forwards all traffic to specific IP behind it. yeah you would most likely want to do that if you plan doing any port forwarding on 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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            • R
              riahc8 @johnpoz
              last edited by

              @johnpoz said in Setup pfSense behind a ISP router that cannot be put into bridge mode (Double NAT):

              @riahc8 For port forwarding, yeah isp routers call that dmz host, etc.. where it forwards all traffic to specific IP behind it. yeah you would most likely want to do that if you plan doing any port forwarding on pfsense.

              From what Im seeing on this ISP router, port forwards automatically opens up the FW rule.

              VPN is working :)

              NAT Loopback isnt but.....I dont know if I currently use it for something although would be niice

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator @riahc8
                last edited by

                @riahc8 said in Setup pfSense behind a ISP router that cannot be put into bridge mode (Double NAT):

                NAT Loopback isnt but.

                Nat reflection or loopback can be problematic for sure in a multinat environment.. Your public IP sits on the isp device.. You would have to set it up on there, but even if worked going to be hairpin nightmare..

                Nat loopback or reflection is a horrible work around to a specific problem and should be avoided whenever possible.

                The only time it really is required to get something to work is when the client wanting to go there does not use local dns, or is hard coded to go to some public IP, etc.

                Getting to something that is local on your network anyway - it is better to just go to the local IP directly, or have whatever fqdn your trying to go to resolve to the local IP vs the public IP, that you would have to reflect back in, creating hairpin traffic and not very optimal.

                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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                • R
                  riahc8
                  last edited by

                  Is there a way to get it to work? Just noticed that I have a bunch of Nagios checks that depend on it :( Dont want to do it all over again

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                  • R
                    riahc8 @riahc8
                    last edited by

                    @riahc8 said in Setup pfSense behind a ISP router that cannot be put into bridge mode (Double NAT):

                    Is there a way to get it to work? Just noticed that I have a bunch of Nagios checks that depend on it :( Dont want to do it all over again

                    Pf, I made a DNS entry un my Pi-Hole pointing to the local address...

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                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator @riahc8
                      last edited by

                      @riahc8 said in Setup pfSense behind a ISP router that cannot be put into bridge mode (Double NAT):

                      Nagios checks that depend on it

                      Checking what exactly.. I would assume your nagios is checking stuff on your local network - why would you use your public IP to get to stuff that is local?

                      Even if nat reflection worked for what your doing, its not really a valid check that public could get to it.

                      I would take the time to setup your nagios to check the local IP of what your wanting to check, or use a fqdn for your different things that resolve to the actual local IP of what your wanting to talk to for a check of something.

                      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

                      R 1 Reply Last reply Reply Quote 0
                      • R
                        riahc8 @johnpoz
                        last edited by riahc8

                        @johnpoz said in Setup pfSense behind a ISP router that cannot be put into bridge mode (Double NAT):

                        @riahc8 said in Setup pfSense behind a ISP router that cannot be put into bridge mode (Double NAT):

                        Nagios checks that depend on it

                        Checking what exactly.. I would assume your nagios is checking stuff on your local network - why would you use your public IP to get to stuff that is local?

                        Even if nat reflection worked for what your doing, its not really a valid check that public could get to it.

                        I would take the time to setup your nagios to check the local IP of what your wanting to check, or use a fqdn for your different things that resolve to the actual local IP of what your wanting to talk to for a check of something.

                        (I think) I fixed it: My DDNS now points to my local IP with a dns entry on the Pi-Hole

                        Dobby_D 1 Reply Last reply Reply Quote 0
                        • Dobby_D
                          Dobby_ @riahc8
                          last edited by

                          @riahc8

                          How do I setup my WAN to get the internet connection from my ISP router?

                          • Connect the pfSense`s WAN port to one
                            LAN port of the ISP router. If there is no
                            switch in game and the pfSense is
                            connected directly to that LAN port you
                            could try out using "Exposed host", but
                            only on that port and for the pfSense!
                            Not for the entire ISP router!

                          Also, can I just disable NAT on the pfSense to avoid the double NAT?

                          NAT on pfSense, is a later process in the pf
                          (packet filter).

                          Will the devices on the LAN interface on
                          the pfSense work?

                          pfSense DHCP: On
                          ISP router DHCP: Off

                          What do I do with VPN setup on the pfSense?
                          If you are using the "Exposed host" method, all
                          traffic will be reaching then the WAN port from
                          the pfSense firewall.

                          #~. @Dobby

                          Turris Omnia - 4 Ports - 2 GB RAM / TurrisOS 7 Release (Btrfs)
                          PC Engines APU4D4 - 4 Ports - 4 GB RAM / pfSense CE 2.7.2 Release (ZFS)
                          PC Engines APU6B4 - 4 Ports - 4 GB RAM / pfSense+ (Plus) 24.03_1 Release (ZFS)

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                          • R
                            riahc8 @Dobby_
                            last edited by

                            @Dobby_ said in Setup pfSense behind a ISP router that cannot be put into bridge mode (Double NAT):

                            Will the devices on the LAN interface on
                            the pfSense work?

                            pfSense DHCP: On
                            ISP router DHCP: Off

                            In my case, I need to leave both on as devices are hanging off the ISP router

                            R 1 Reply Last reply Reply Quote 0
                            • R
                              riahc8 @riahc8
                              last edited by

                              @riahc8 said in Setup pfSense behind a ISP router that cannot be put into bridge mode (Double NAT):

                              @Dobby_ said in Setup pfSense behind a ISP router that cannot be put into bridge mode (Double NAT):

                              Will the devices on the LAN interface on
                              the pfSense work?

                              pfSense DHCP: On
                              ISP router DHCP: Off

                              In my case, I need to leave both on as devices are hanging off the ISP router

                              Related subject: https://forum.netgate.com/topic/180704/access-network-behind-a-double-nat

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