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    Routing a service to non-default WAN

    Scheduled Pinned Locked Moved Routing and Multi WAN
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    • M
      mik256 @viragomann
      last edited by mik256

      @viragomann said in Routing a service to non-default WAN:

      The second packet doesn't seem to be a response to the first one, but an additional connection.

      On which interface of pfSense to you see this?
      I'm not expect to see this on PE3 / WAN2. Otherwise you've probably configured the outbound NAT wrongly.

      You are correct. There's a different port number being used. Maybe that's how socat works. I think ipsec didn't behave like this, but I will find out.

      And also this controverts your statement above:

      pfsense replies with correct IP but on wrong interface :(

      Now what? Wrong IP or wrong interface?

      It's still the same, sorry for the confusion. On pfsense tcpdump shows WAN2 IP is used for reply, but using tcpdump on WAN1 interface. If I do packet capture on WAN2, I don't see any reply being send at all.

      I tried with http (pfsense web ui) and there reply-to worked fine: wget from a host to WAN2 received html from WAN2 public ip. Maybe reply-to fails just for udp?

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      • V
        viragomann @mik256
        last edited by

        @mik256 said in Routing a service to non-default WAN:

        Maybe that's how socat works. I think ipsec didn't behave like this, but I will find out.

        I'd expect that a device sends a response to the source IP and port it found in the request packet.
        So this capture doesn't seem to be suitable to troubleshoot this for me.

        Maybe reply-to fails just for udp?

        Just make a test with a custom rule for IPSec.
        Add a rule to WAN2 allowing IPSec traffic to the interface IP (if the service is running on pfSense itself), enable logging and state a unique description.
        Custom rules should override automatic rule and should hence be applied.

        Try to connect from remote and check in the firewall log if the rule was applied.

        Reply-to only affects to replies. If pfSense itself initiates a connection it will follow the routing table.
        So if you want to use a certain gateway you will have to set the routes respectively.
        However, if I remember correctly, it's possible to policy route traffic with a floating rule for direction 'out'.

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        • M
          mik256 @viragomann
          last edited by

          @viragomann said in Routing a service to non-default WAN:

          Add a rule to WAN2 allowing IPSec traffic to the interface IP (if the service is running on pfSense itself), enable logging and state a unique description.

          Sounds like what I did first before started with policy routing, NAT etc. to get it working.

          Meanwhile, I really don't know what did the trick, but it started working somehow as expected.
          Such a relief after so many hours:)
          Thank you so much guys!!

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          • stephenw10S
            stephenw10 Netgate Administrator
            last edited by

            So you added a rule back to pass the IPSec traffic on PE3 overriding the auto-rules?

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            • M
              mik256 @stephenw10
              last edited by

              @stephenw10

              My setup now is this: no policy rules, no static rules, no manual NAT rules. Default GW is WAN1, ipsec listens on WAN2. I have manually opened udp/500 and udp/4500 on WAN2 (no gw set). I think, that was my setup in the first shot. When I tried to disable these 2 rules, it stopped working even though I can't see any denied packets in firewall log. When I added the static routing to the remote ip (still without rules to pass udp/500 and udp/4500 on WAN2), it works.

              So it seems that to get pfsense work correctly as initiator on non-default wan you either need to:
              set a static routing rule to remote endpoint with the non-default wan
              or
              set udp/500 and udp/4500 permit rules on the non-default wan
              otherwise pfsense sends replies with the default wan instead.

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              • stephenw10S
                stephenw10 Netgate Administrator
                last edited by

                When pfSense is the initiator it should be the route-to rule that sends traffic via the WAN2 gateway when it's sourced from the WAN2 IP.

                When the other side initiates reply-to should apply.

                However the auto rules do not appear to add reply-to. Which is interesting.

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                • M
                  mik256 @stephenw10
                  last edited by

                  @stephenw10 said in Routing a service to non-default WAN:

                  When the other side initiates reply-to should apply.

                  However the auto rules do not appear to add reply-to. Which is interesting.

                  Pfsense is the responder in my case. Yes, it confused me a lot :) I was about to introduce some wild workarounds. So glad we got it working! Thanks a lot to both of you guys.

                  M 1 Reply Last reply Reply Quote 1
                  • M
                    mik256 @mik256
                    last edited by mik256

                    @mik256 lol, again same issue:) this time with openvpn. Tried all common tricks: policy routing, nat, playing with firewall rules with and without specifying gateway, but openvpn just keeps replying on default wan. Why the hell i just can't make it reply on the interface the request came from:( btw can't really see what policy routing (setting gw in fw rule) could be good for, when the routing takes place before that.

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                    • stephenw10S
                      stephenw10 Netgate Administrator
                      last edited by

                      So for remote clients connecting to pfSense?

                      The same thing applies, reply-to should normally pass replies back out of the same WAN as long as the rule passing it in one the specific WAN interface.

                      However openvpn has some additional setup options for multiwan that can be used instead. So how is it configured?

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                      • M
                        mik256 @stephenw10
                        last edited by

                        @stephenw10
                        Yes, remote clients connecting to pfsense. OpenVPN server is listening on LAN (only this interface, there is a port forwarding from another firewall). Tried TCP/UDP. Tcpdump shows requests from clients arrive on hn0 (LAN), but replies are sent from hn1 (WAN), while they need to send back to the firewall.

                        Besides that, I didn't find any additional setup options which might be relevant in openvpn server settings, which do you mean?

                        Thanks

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                        • M
                          mik256 @stephenw10
                          last edited by

                          @stephenw10
                          I found how to deal with that: instead of using LAN for openvpn server, I used a new VLAN interface which has default gateway set to the port forwarding firewall. Nothing else needed to be changed.

                          Seems like having a gatway on interface pfsense treats this interface differently a correctly sends replies.

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                          • stephenw10S
                            stephenw10 Netgate Administrator @stephenw10
                            last edited by

                            @stephenw10 said in Routing a service to non-default WAN:

                            Is the gateway actually defined on the interface? That's what configures it as a WAN with reply-to and route-to on rules.

                            Yup, exactly. ๐Ÿ˜‰ Reply-to only applies to WAN type interfaces.

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                            • M
                              mik256 @stephenw10
                              last edited by

                              @stephenw10
                              cool! my bad I didn't read this carefully. thanks

                              1 Reply Last reply Reply Quote 1
                              • stephenw10S
                                stephenw10 Netgate Administrator
                                last edited by

                                No worries. I remember hitting that issue myself when I first setup pfSense with multiwan. Too long ago to mention!

                                Until you realise how pfSense determines what is a WAN interface and what that triggers it can easily seem like magic. ๐Ÿ˜‰

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