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    Accessing modem from inside firewall

    NAT
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    • B
      balubeto
      last edited by

      Hi

      I read the guide https://doc.pfsense.org/index.php/Accessing_modem_from_inside_firewall and it seems to me that there is a mismatch:

      In the first part, it indicates that the modem must have a different subnet from the LAN: So if, for example, the LAN belongs to class C, the modem may belong to class A.

      While, in the second part, it indicates that their subnet should be the same.

      I am wrong?

      Thanks

      Bye

      balubeto

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      • DerelictD
        Derelict LAYER 8 Netgate
        last edited by

        You need to have a VIP on LAN on the same subnet as the modem and NAT out that VIP when the destination is the modem so it doesn't have to have a route back to you (since it won't have one)

        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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        • B
          balubeto
          last edited by

          @Derelict:

          You need to have a VIP on LAN on the same subnet as the modem and NAT out that VIP when the destination is the modem so it doesn't have to have a route back to you (since it won't have one)

          Excuse me but what is a VIP?

          Thanks

          Bye

          balubeto

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          • pttP
            ptt Rebel Alliance
            last edited by

            @balubeto:

            Excuse me but what is a VIP?

            https://doc.pfsense.org/index.php/What_are_Virtual_IP_Addresses

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            • B
              balubeto
              last edited by

              I have a VDSL2 router (10.0.0.1) in bridge mode connected to the WAN port on a hardware firewall (192.168.1.1) which manages the Internet connection using the PPPoE.

              Since the WAN interface of the firewall is become a virtual adapter PPPoE-WAN, associated with the re2 physical interface, I assigned the re2 physical interface and I set it to 10.0.0.2.

              Now, what are the rules that I will have to create in the Virtual IP and NAT sections to make sure that I am able to access the web interface of the router?

              I've been using pfSense 2.3.2 64 bit.

              Thanks

              Bye

              balubeto

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              • B
                balubeto
                last edited by

                I'm still waiting for your answer.

                Thanks

                Bye

                balubeto

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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by

                  "I have a VDSL2 router (10.0.0.1)"
                  "I assigned the re2 physical interface and I set it to 10.0.0.1"

                  How do you expect that to work??  Just curious… Do you mean you set re2 to 10.0.0.2?

                  So what do you think you should do for nat, if your wanting to talk to a client on a 10 network on your wan interface that has no gateway and doesn't understand how to get to your 192.168 network on your lan??  Hint if you "nat" your 192.168 traffic to look like its coming from a 10 address, then your "router" will no how to talk back ;)

                  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 2.7.2, 24.11

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                  • B
                    balubeto
                    last edited by

                    @johnpoz:

                    "I have a VDSL2 router (10.0.0.1)"
                    "I assigned the re2 physical interface and I set it to 10.0.0.1"

                    How do you expect that to work??  Just curious… Do you mean you set re2 to 10.0.0.2?

                    So what do you think you should do for nat, if your wanting to talk to a client on a 10 network on your wan interface that has no gateway and doesn't understand how to get to your 192.168 network on your lan??  Hint if you "nat" your 192.168 traffic to look like its coming from a 10 address, then your "router" will no how to talk back ;)

                    I was wrong to write: the re2 physical interface has the IP 1.0.0.2.

                    With these settings, it is possible to reach my goal? If so, how should I do? If not, what are the addresses of the router and re2 interface appropriate for do this?

                    Thanks

                    Bye

                    balubeto

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                    • B
                      balubeto
                      last edited by

                      Sorry but there is someone willing to help me?

                      Thanks

                      Bye

                      balubeto

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                      • johnpozJ
                        johnpoz LAYER 8 Global Moderator
                        last edited by

                        So create an outbound nat using the vip you created of 10.0.0.2 - do you need a picture?

                        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 2.7.2, 24.11

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                        • B
                          balubeto
                          last edited by

                          @johnpoz:

                          So create an outbound nat using the vip you created of 10.0.0.2 - do you need a picture?

                          How should I fill out this window:


                          ?

                          Thanks

                          Bye

                          balubeto

                          1 Reply Last reply Reply Quote 0
                          • pttP
                            ptt Rebel Alliance
                            last edited by

                            This is how i have it done….  No "VIP" here...

                            ADSL Modem in "Bridge"  with 172.20.254.1/29 IP address

                            pfSense WAN PPPoE (re1)

                            Modem Access Interface  "GEST"  (means: "gestión" = management)  ;)  (re1) with 172.20.254.6/29 IP address

                            The rest of the info, in the attached images ;)

                            001.png
                            001.png_thumb
                            002.png
                            002.png_thumb
                            003.png
                            003.png_thumb
                            004.png
                            004.png_thumb
                            005.png
                            005.png_thumb
                            006.png
                            006.png_thumb

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                            • B
                              balubeto
                              last edited by

                              @ptt:

                              This is how i have it done….  No "VIP" here...

                              ADSL Modem in "Bridge"  with 172.20.254.1/29 IP address

                              pfSense WAN PPPoE (re1)

                              Modem Access Interface  "GEST"  (means: "gestión" = management)  ;)  (re1) with 172.20.254.6/29 IP address

                              The rest of the info, in the attached images ;)

                              I can not understand the 003 image. What rules should I add?

                              Thanks

                              Bye

                              balubeto

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

                                Good catch ptt, no you do not need a vip if your NOT using the wan interface IP I guess.  Good catch that his wan is actually PPPoE.  I was over looking that.

                                But I would not suggest manual mode for the outbound nat, just use hybrid and add the nat for interface that is connected to your modem.

                                This is really no different than using a vip, but since your really not actually using the IP that is on your physical interface connected to your modem, you can just set the IP right on the interface and no need for a vip.

                                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 2.7.2, 24.11

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                                • DerelictD
                                  Derelict LAYER 8 Netgate
                                  last edited by

                                  Yeah PPPoE is done differently. That writeup has you putting the IP subnet of the modem on the physical interface the PPPoE is on. No VIPs there.

                                  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)

                                  1 Reply Last reply Reply Quote 0
                                  • B
                                    balubeto
                                    last edited by

                                    I can not understand the 003 image. What rules should I add?

                                    Thanks

                                    Bye

                                    balubeto

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

                                      that is not a rule.. That is the actual interface connected to the modem.. Just putting an IP address on it that matches with the IP address of the modems IP.

                                      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 2.7.2, 24.11

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                                      • pttP
                                        ptt Rebel Alliance
                                        last edited by

                                        You create & configure the "Interface" for modem access (GEST in my case)

                                        then, as John pointed, you set the NAT as "Hybrid"

                                        now, you create the NAT Rule (Mapping) to access the Modem…

                                        That's all..

                                        NAT_Hybrid.png
                                        NAT_Hybrid.png_thumb
                                        NAT_CFG.png
                                        NAT_CFG.png_thumb

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                                        • B
                                          balubeto
                                          last edited by

                                          Firewall 192.168.1.1
                                          Router 10.0.0.1

                                          I configured the router in bridge mode and have configured the firewall in this way





                                          When I connect my router to the WAN port on the firewall, I can't access the router. Where did a mistake?

                                          Thank you,

                                          Bye

                                          balubeto

                                          1 Reply Last reply Reply Quote 0
                                          • pttP
                                            ptt Rebel Alliance
                                            last edited by

                                            Your NAT setting is wrong ….  Set/leave it as "Hybrid Outbound NAT"

                                            ![Your NAT is wrong.jpg](/public/imported_attachments/1/Your NAT is wrong.jpg)
                                            ![Your NAT is wrong.jpg_thumb](/public/imported_attachments/1/Your NAT is wrong.jpg_thumb)

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