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    Using Open VPN service on XG-7100, prevent LAN clients connecting

    Scheduled Pinned Locked Moved Firewalling
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    • JKnottJ
      JKnott @shapelytraffic
      last edited by

      @shapelytraffic said in Using Open VPN service on XG-7100, prevent LAN clients connecting:

      @Derelict so, if I understand you correctly, you're saying to block private addresses on the WAN rule set to the WAN IP?

      One very important thing to remember is that the rules are applied to the interface, not the address. So, you have to put the rule on the interface that the packets will pass through. If you try to reach the WAN address from the LAN, the packets will pass through the LAN interface, but not the WAN interface, so the rules go on the LAN interface.

      PfSense running on Qotom mini PC
      i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
      UniFi AC-Lite access point

      I haven't lost my mind. It's around here...somewhere...

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      • S
        shapelytraffic @Derelict
        last edited by

        @Derelict I'm not certain we agree specifically what my desired effect is though. I would feel much more confident in your assistance if you would express to me what you think I'm trying to do, because in my mind it's not at all unusual. But your phrasing sounds skeptical.

        JKnottJ 1 Reply Last reply Reply Quote 0
        • DerelictD
          Derelict LAYER 8 Netgate
          last edited by Derelict

          You do not want inside hosts to be able to connect to your OpenVPN server on the WAN address.

          So you need to block those connections on the inside interfaces.

          I'm pretty much done here. Can only say the same thing so many times. There is a book.

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          • S
            shapelytraffic @Derelict
            last edited by

            @Derelict good on ya mate. How can I be as good as you.

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            • JKnottJ
              JKnott @shapelytraffic
              last edited by

              @shapelytraffic said in Using Open VPN service on XG-7100, prevent LAN clients connecting:

              @Derelict I'm not certain we agree specifically what my desired effect is though. I would feel much more confident in your assistance if you would express to me what you think I'm trying to do, because in my mind it's not at all unusual. But your phrasing sounds skeptical.

              You want to keep LAN users from using the VPN. So, all you have to do is block them with a rule on the LAN interface. Also, even if they did connect it, the VPN still won't be used, because there is a direct connection that bypasses the it and that connection will always be used.

              You may need to brush up on how IP works. When you try to connect to something, the computer compares the destination address with the local network address and subnet mask. If the destination is on the same network, then the packet is sent directly to the destination. Any other destination requires routing and you can't route to your own network, as you'd be doing if you passed through the VPN.

              PfSense running on Qotom mini PC
              i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
              UniFi AC-Lite access point

              I haven't lost my mind. It's around here...somewhere...

              S 1 Reply Last reply Reply Quote 0
              • S
                shapelytraffic @JKnott
                last edited by

                @JKnott thanks for taking the time to condescend. No thanks.

                JKnottJ 1 Reply Last reply Reply Quote 0
                • JKnottJ
                  JKnott @shapelytraffic
                  last edited by

                  @shapelytraffic

                  I wasn't trying to be condescending. You seemed to be having a problem understanding how it works.

                  PfSense running on Qotom mini PC
                  i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                  UniFi AC-Lite access point

                  I haven't lost my mind. It's around here...somewhere...

                  S 1 Reply Last reply Reply Quote 0
                  • S
                    shapelytraffic @JKnott
                    last edited by

                    @JKnott you must have worked with any other kind of firewall that provides a VPN client (ex: SonicWall). In my experience, you don't have to roll your sleeves up to prevent LAN traffic from initiating the VPN. - you can't go in through the out door.

                    What I'm not understanding is why there isn't a prefab to do this?

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                    • S
                      shapelytraffic
                      last edited by

                      I mean, if you go back to the first comments, it's clear that there was a misunderstanding. One which was not admitted to.

                      JKnottJ 1 Reply Last reply Reply Quote 0
                      • JKnottJ
                        JKnott @shapelytraffic
                        last edited by

                        @shapelytraffic

                        Is that SonicWall just a firewall? Or firewall/router? Entirely different devices. The purpose of a router is to route packets from one network to another. PfSense does that, but also has filtering so that it can be used as a firewall. Since the LAN and WAN are different networks, pfSense routes the packets. It makes no difference what the address is, if it's on the WAN interface, it gets routed in that direction, just as would a packet for the ISPs gateway. Then there's the added factor in that the WAN address is one of at least two valid addresses for the pfSense box. You're asking for something extra to block that VPN connection and that is a rule on the LAN interface. Also, think of other things that you might want to do. For example, in testing, you may want to use a specific interface, to ensure routing is working. So, from the LAN, you could ping the WAN address to verify it works. Or you could tell it to ping from a specific interface out onto the LAN. If you ping from the WAN, the replies have to be able to come back. Again, you have to configure what you want with the rules. That's what they're there for.

                        PfSense running on Qotom mini PC
                        i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                        UniFi AC-Lite access point

                        I haven't lost my mind. It's around here...somewhere...

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                        • S
                          shapelytraffic
                          last edited by

                          This post is deleted!
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                          • stephenw10S
                            stephenw10 Netgate Administrator
                            last edited by

                            There is usually no reason to block clients connecting a VPN from an internal interface. If that have access to the VPN then it's not a security issue anyway. At worst it might cause routing issues for clients who accidentally connect to the VPN when they are on the internal subnet.
                            If you don't want to ever happen for some reason you can make a floating reject rule with destination WAN address and port the VPN port and apply that to all the interfaces you want it on.

                            Steve

                            S 1 Reply Last reply Reply Quote 1
                            • S
                              shapelytraffic @stephenw10
                              last edited by

                              @stephenw10 thanks for an easy answer. :D

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                              • DerelictD
                                Derelict LAYER 8 Netgate
                                last edited by

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                                • P
                                  Pelispedia Banned
                                  last edited by

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