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    Pfsense setup question CGNAT

    Scheduled Pinned Locked Moved General pfSense Questions
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    • V
      viragomann @Crossy2
      last edited by

      @Crossy2 said in Pfsense setup question CGNAT:

      But I always heard having 2 DHCP servers running is a bad thing.

      This concerns multiple DHCP on the same L2 network, but your WAN and LAN are 2 separated L2.

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      • C
        Crossy2 @viragomann
        last edited by

        @viragomann

        Aha that explains it. Thx 👍

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        • NollipfSenseN
          NollipfSense @Crossy2
          last edited by NollipfSense

          @Crossy2 said in Pfsense setup question CGNAT:

          I would use the Google DNS or Cloudflare instead of the ISP one

          I have this setup currently except I use pfSense itself for DNS. BTW, can confirm that triple NAT works too.

          pfSense+ 23.09 Lenovo Thinkcentre M93P SFF Quadcore i7 dual Raid-ZFS 128GB-SSD 32GB-RAM PCI-Intel i350-t4 NIC, -Intel QAT 8950.
          pfSense+ 23.09 VM-Proxmox, Dell Precision Xeon-W2155 Nvme 500GB-ZFS 128GB-RAM PCIe-Intel i350-t4, Intel QAT-8950, P-cloud.

          1 Reply Last reply Reply Quote 1
          • Dobby_D
            Dobby_ @Crossy2
            last edited by

            @Crossy2 said in Pfsense setup question CGNAT:

            But I always heard having 2 DHCP servers running is a bad thing.

            If you have behind the ISP router a NAS or other
            devices and you want to reach them from devices behind the pfSense firewall (LAN) then it is perhaps
            causing errors.

            #~. @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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            • C
              Crossy2 @Dobby_
              last edited by

              @Dobby_

              Do you mean the NAS being in the DMZ?

              My ultimate goal but (I think) it’s not doable because I’m behind CGNAT would to use Wireguard to access my NAS which is inside of my LAN.
              (That is something for the future)

              Dobby_D 1 Reply Last reply Reply Quote 0
              • Dobby_D
                Dobby_ @Crossy2
                last edited by

                @Crossy2 said in Pfsense setup question CGNAT:

                Do you mean the NAS being in the DMZ?

                DMZ types

                • "pseudo" DMZ
                  Exposed Host, non real and only in some cases
                • Real DMZ (clean dmz)
                  Bastion host, dual homed router or firewall combination: Internet > Router > DMZ > Firewall
                • non real DMZ (dirty dmz)
                  DMZ Port at the router or firewall

                DMZ port types (routers or firewall)

                • A real dedicated DMZ port
                  A single port, with its own switch chip,
                  no other data will running over, only for
                  that port made and able to use
                • A non real dedicated DMZ port
                  Many port will be connected to one and the same switch chip and all their data runs together over that switch chip but the port can configured
                  as a DMZ port
                • A DMZ port
                  One LAN port will be used as a DMZ port only with another IP range and port will be opened
                  to the internet and back into that pseudo DMZ

                My ultimate goal but (I think) it’s not doable because I’m behind CGNAT would to use Wireguard to access my NAS which is inside of my LAN.

                You will need a so called jump host else where
                in the internet placed, perhaps at a hoster.
                You will be able to reach that host from everywhere and it is connected to your home
                network, so CGNAT is not anymore the problem.

                In the DMZ you will be able to reach your NAS from the outsite (over the internet) and from the
                inside of your LAN. If you are VPN at home, the
                NAS will be "safe" and in normal all such devices will be placed inside of a DMZ, so if you are now
                opening ports at the second router or firewall,
                you will be opening your LAN too, but this
                should be secured by the second router or firewall!

                For sure everybody can do what he want or is able to realize, but how much more and often
                you will be setting up special work arounds you
                will be ending at one day up with more problems
                then you will own.

                #~. @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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                • C
                  Crossy2 @Dobby_
                  last edited by Crossy2

                  @Dobby_

                  Thx, food for thought.

                  This is something for the distant future, let me first try to make my home network a bit more secure.

                  This whole coming exercise is also because we are getting solar in the next weeks and the inverters do need to be connected to the WWW (Via WiFi). And I don’t want them to snoop around in my LAN read PC, NAS etc, but I would still like to be able to manage them.

                  So
                  inverter -> WWW oke
                  Inverter -> LAN not oke
                  Main PC -> Inverter oke

                  Dobby_D 1 Reply Last reply Reply Quote 0
                  • Dobby_D
                    Dobby_ @Crossy2
                    last edited by

                    @Crossy2 said in Pfsense setup question CGNAT:

                    This is something for the distant future, let me first try to make my home network a bit more secure.

                    Ok forget that the CGNAT exists! It is only well to know for you if you want VPN in over the internet!

                    This whole coming exercise is also because we are getting solar in the next weeks and the inverters do need to be connected to the WWW (Via WiFi).

                    For sure that is ok.

                    And I don’t want them to snoop around in my > LAN read PC, NAS etc, but I would still like to be able to manage them.

                    Ok, and you must use the router from your ISP?
                    Or can you also take a modem in front of your
                    pfSense? Make things more easy for you.

                    So
                    inverter -> WWW oke

                    Set the inverter inside the dmz (between the )
                    ISP router and the pfSense. Now it could be having a connect to the internet with ease
                    and you could over VPN connect to it.

                    The pfSense is then securing your entire LAN.
                    Because it is behind the IPS router!

                    Inverter -> LAN not oke

                    If you open now ports at the pfSense WAN
                    it is not so secured as you may want it!

                    Main PC -> Inverter oke

                    If the inverter is in the DMZ between the both routers you can connect from the PC in the LAN
                    to it (routes) and from the outside (internet) you
                    could connect too, to that inverter as I see it right.

                    #~. @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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                    • C
                      Crossy2 @Dobby_
                      last edited by Crossy2

                      @Dobby_ said in Pfsense setup question CGNAT:

                      If the inverter is in the DMZ between the both routers you can connect from the PC in the LAN
                      to it (routes) and from the outside (internet) you
                      could connect too, to that inverter as I see it right.

                      I could connect an WAP to the ISP Router and have the Inverters connect to that because they only connect via Wifi. That would be an easy solution and I have a Spare router available.

                      The Inverters can then go out separate from my Network but I am not able to reach them remotely (on the road) but that is for now a total NON issue. Brilliant idea! Thx

                      So for my Understanding plug the WAP into a Lan port on the ISP Router so it gets an IP from the ISP Router and then it's in DMZ? Correct?

                      Do you have a link for me to read up about on creating those routes from the PfSense to the WAP in the DMZ?

                      Re: ISP Router

                      The router from ISP I must use. It's fiber and they don't want
                      A) set the Router in Bridge Mode
                      B) give me the PPoE username and Pwd.
                      It's one of those ZTE Routers.

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                      • S
                        SteveITS Galactic Empire @Crossy2
                        last edited by

                        @Crossy2 To connect from your LAN through a router in the pfSense WAN to your inverter you don’t need anything on pfSense. Just a port forward on that other router. IPv4 only if possible in case your ISP adds IPv6 someday, so the Internet can’t connect to it; or else limit the port forward to your pfSense WAN IP.

                        Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
                        When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
                        Upvote 👍 helpful posts!

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                        • C
                          Crossy2 @SteveITS
                          last edited by Crossy2

                          @SteveITS

                          So for my understanding, to access the WAP (Wireless Access point) which is connected to a port of my Router ISP and I want to connect to the WAP from the LAN side I don’t need to do anything but still need to open a port ?

                          Which ports do I HAVE to open? 80? To reach the management interface for example.

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                          • S
                            SteveITS Galactic Empire @Crossy2
                            last edited by

                            @Crossy2 if your pfSense WAN and AP are both connected to the ISP LAN then your pfSense LAN can talk to it and other devices “out there” because pfSense will NAT the request to that network. I thought you were using a router, perhaps that was a different thread.

                            Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
                            When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
                            Upvote 👍 helpful posts!

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                            • C
                              Crossy2 @SteveITS
                              last edited by Crossy2

                              @SteveITS

                              No worries, thx for taking your time to reply

                              Unfortunately I can’t make a drawing as I am not at home.

                              But the situation is this currently

                              WWW - CGNAT - ISP ROUTER - LAN

                              And I want it to be

                              WWW - CGNAT - ISP ROUTER - PFSENSE - LAN

                              And the WAP could be placed like this

                              WWW - CGNAT - ISP ROUTER - WAP - PFSENSE - LAN

                              So the the WAP will be connected to a port on the ISP router and the WAN interface of the PFSENSE is also connected to a Port on the ISP router.

                              Edit: will I need to setup some block/allow rules to prevent the WAP to access the LAN but the LAN to be able to access the WAP?

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                              • S
                                SteveITS Galactic Empire @Crossy2
                                last edited by

                                @Crossy2 A true AP will put those devices on the pfSense WAN network. They are all on the iSP router LAN.

                                pfSense WAN blocks all incoming traffic by default.

                                pfSense LAN has an allow all by default so can access devices in WAN.

                                Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
                                When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
                                Upvote 👍 helpful posts!

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                                • C
                                  Crossy2 @SteveITS
                                  last edited by Crossy2

                                  @SteveITS

                                  Thx again.

                                  It’s an asus router I still have I would like to use as AP for the inverters

                                  asus rt-n12

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                                  • S
                                    SteveITS Galactic Empire @Crossy2
                                    last edited by

                                    @Crossy2 If it has AP mode then the above applies. Some routers let you plug in only LAN and thus act like an AP. If it will only be a router then you can forward a port to your inverter on its LAN.

                                    Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
                                    When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
                                    Upvote 👍 helpful posts!

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                                    • C
                                      Crossy2 @SteveITS
                                      last edited by

                                      @SteveITS

                                      Yep it has I believe 3 modes and one of those is AP.

                                      I will do some testing and report back but could be a while as I am not at home due to personal circumstances but will report back.

                                      That option to place the AP there is a really great one as it also frees up a port on the Pfsense SG-1100 (I ordered one before I came to this forum, if I knew then what I know I would have ordered a 2100 😂😉

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