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    WireGuard on pfSense behind ISP router. Why do I need a static route?

    Scheduled Pinned Locked Moved Routing and Multi WAN
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      viragomann @dangersheep
      last edited by

      @dangersheep said in WireGuard on pfSense behind ISP router. Why do I need a static route?:

      reconfigure your network and put pfSense in between the router and the LAN

      I'm sorry, I don't completely understand. Do you mean, put pfSense in front of the ISP router, facing the internet?

      I assume, you need the ISP router for your internet connection. Otherwise you could replace it with the pfSense box.
      However, with ISP router you can it set up this way: Internet > ISP router > pfSense > LAN subnet

      Maybe I misunderstood you post and you've it set up this way already?

      Obey what @Bob-Dig wrote above.
      Obviously I didn't read all your text before.

      You must not state an IP in the WG interface settings and you must not state a gateway there at all.
      Anyway there is no need to assign an interface to the WG instance as long as you don't need to policy route traffic to the remote site or other special purposes.

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        dangersheep @Bob.Dig
        last edited by

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          dangersheep @viragomann
          last edited by

          @viragomann said in WireGuard on pfSense behind ISP router. Why do I need a static route?:

          Maybe I misunderstood you post and you've it set up this way already?

          Yes, that's the current setup: https://imgur.com/a/B1xla5Y
          What's confusing, I suppose, is that there are two "LAN"s - one for the ISP router (which includes the WAN address of the pfSense box) and one behind pfSense.

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            dangersheep @viragomann
            last edited by

            @viragomann said in WireGuard on pfSense behind ISP router. Why do I need a static route?:

            You must not state an IP in the WG interface settings and you must not state a gateway there at all.
            Anyway there is no need to assign an interface to the WG instance as long as you don't need to policy route traffic to the remote site or other special purposes.

            OK, I've removed the WG interface, moved the 'allow WG traffic' rule to the WireGuard tab, and removed the static route for WG traffic and the dedicated gateway rule for WG. But things are not working. I can establish a handshake, but my phone WG_PEER cannot even ping the WG_HOST interface (10.0.100.1).

            Any clues as to what I'm doing wrong? The WireGuard firewall rule is trivial: all IPv4 traffic is allowed from * source to * destination.

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              viragomann @dangersheep
              last edited by

              @dangersheep
              Yes, and also LAN devices are missing in the drawing.

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                dangersheep @viragomann
                last edited by

                @viragomann
                Right, i figured that would confuse things but it might have been good to specify which LAN I was talking about. I'm referring to the LAN behind pfSense. Once I'm established on the wg tunnel with handshake performed, I can't even ping the other end of the wireguard tunnel (the WG_HOST interface) let alone the pfSense LAN interface.

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                  viragomann @dangersheep
                  last edited by

                  @dangersheep
                  Did you remove the interface already or at least the IP and gateway settings?

                  Did you add a firewall rule to Wireguard or even the specific interface to allow access?

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                    dangersheep @Bob.Dig
                    last edited by

                    @Bob-Dig Thank you. I've followed all your instructions. I've deleted the static route; I've deleted the wireguard gateway (now it defaults to WAN_DHCP); I've deleted the assigned interface for wireguard. However, the most I can do is establish a handshake.

                    On my phone with wg active, I see a 'healthy' tx volume (23 KiB) after a minute or two, but just 700 B of rx traffic. The connection doesn't seem to be replying 'properly'

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                      dangersheep @viragomann
                      last edited by

                      @viragomann said in WireGuard on pfSense behind ISP router. Why do I need a static route?:

                      Did you remove the interface already or at least the IP and gateway settings?

                      I removed the assigned interface. And I removed the gateway dedicated to WG. Now I only have one gateway (for each IPv4 and v6) and I explicitly made "WAN_DHCP(6)" the default gateway for pfSense.

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                        dangersheep @viragomann
                        last edited by

                        @viragomann said in WireGuard on pfSense behind ISP router. Why do I need a static route?:

                        Did you add a firewall rule to Wireguard or even the specific interface to allow access?

                        Yes.

                        On the WAN interface, there is one rule allowing all IPv4 UDP traffic addressed to the port 51820 on the WAN interface to pass.

                        On the WireGuard firewall tab (there is no longer a tab for the assigned interface - deleted - so this is just whatever default WireGuard 'interface' exists) there is just one rule that allows all IPv4 traffic to pass from any source/port to any source/port.

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                          viragomann @dangersheep
                          last edited by

                          @dangersheep
                          So you should be able to ping the WG server IP and the pfSense LAN IP as well at least. Doesn't this work?

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                            dangersheep @dangersheep
                            last edited by

                            @viragomann

                            As for how the rules are performing, I log when the WAN -> WG rule is passed, and I see that happening, with UDP traffic addressed to WAN_ADDRESS:51820.

                            There is lots of blocked UDP traffic on WAN_ADDRESS but it seems to be mainly on port 137 coming from all sorts of ports on the upstream ISP-router LAN address = default gateway.

                            In passing, why would there be traffic directed to pfSense_WAN:137 from the upstream gateway? I guess that's a response to a filesharing service somewhere behind pfSense - would that make any sense?

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                              dangersheep @viragomann
                              last edited by

                              @viragomann said in WireGuard on pfSense behind ISP router. Why do I need a static route?:

                              So you should be able to ping the WG server IP and the pfSense LAN IP as well at least. Doesn't this work?

                              No, that does not work. pfSense is configured to respond to ping and does so from a device on the LAN subnet. But when connected to the wireguard tunnel, it is not possible to ping anything.

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                                dangersheep @dangersheep
                                last edited by

                                @viragomann

                                I can, for example, run wireshark on the wg interface on a device (using my phone data as hotspot). The handshake completes, but when I try to ping I see the ICMP traffic leaving 10.0.100.2 with destination 10.0.100.1 but never any reply.

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                                  dangersheep @dangersheep
                                  last edited by

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                                    viragomann @dangersheep
                                    last edited by

                                    @dangersheep said in WireGuard on pfSense behind ISP router. Why do I need a static route?:

                                    In passing, why would there be traffic directed to pfSense_WAN:137 from the upstream gateway? I guess that's a response to a filesharing service somewhere behind pfSense - would that make any sense?

                                    If you're running the filesharing behind pfSense and didn't expose it, there should no related packets be seen on the WAN.

                                    Maybe the router just tries to get NetBIOS informations.

                                    Für Kurviger habe ich ein Tourer+ Jahresabo, eben auch, um das Projekt zu unterstützen. Mal sehen,

                                    Do you see the packets, when sniffing the traffic on pfSense on the WG interface?

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                                      dangersheep @viragomann
                                      last edited by

                                      @viragomann said in WireGuard on pfSense behind ISP router. Why do I need a static route?:

                                      Do you see the packets, when sniffing the traffic on pfSense on the WG interface?

                                      So, I can see the handshake, watching the traffic on the wg interface from my remote device.

                                      And I can see the ICMP arriving on the pfSense WG interface:
                                      HH:53:42.411647 IP 10.0.100.2 > 10.0.100.1: ICMP echo request, id 18, seq 1, length 64

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                                        viragomann @dangersheep
                                        last edited by

                                        @dangersheep
                                        But no response?

                                        To get sure, if you go to Status > Gateways, is there any other gateway shown up aside from the WAN?

                                        Does pfSense and the LAN devices even have internet access?

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                                          dangersheep @viragomann
                                          last edited by

                                          @viragomann
                                          No reply, no. I just see that line.

                                          Status > Gateways just shows the ISP router LAN interface address (ipv4 and 6) and both are 'online. No other gateways.

                                          pfsense and the LAN devices both have internet access.

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                                            dangersheep @dangersheep
                                            last edited by

                                            @dangersheep
                                            If I watch the pfSense LAN interface and ping from a device on that subnet, I get a response and I see the full request-reply exchange in the pfSense packet capture, so I think I'm doing it right.

                                            There's really nothing coming back out of the WG interface.

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