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    Multiple Gateways on same subnet

    Scheduled Pinned Locked Moved Routing and Multi WAN
    multi-wansubnetgatewayroutingfirewall
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    • D
      dr_tech @DaddyGo
      last edited by

      @DaddyGo said in Multiple Gateways on same subnet:

      Place the WAN static IP on the same network as the gateway

      The WAN static IP is on the same subnet as the other two routers, here is a flowchart to show the same in a better way :

      Picture1.png

      The reason for this setup is, that my campus provides a very high speed (1Gbps) connection, which is highly filtered (a lot of sites blocked), while my ISP offers unrestricted access to all sites, but the bandwidth is only 50Mbps. Hence, I am looking into load balancing first, then I'll setup up some firewall rules to use a specific gateway based on IP address.

      I need a 1Gbps connection since some files I download (DICOM images from CT scanners and X Ray machines) are sometimes as large as 2-4 gigs, and I sometimes need to download as many as 20 files a day.

      DaddyGoD 1 Reply Last reply Reply Quote 0
      • DaddyGoD
        DaddyGo @dr_tech
        last edited by

        @dr_tech

        ok I see...

        the gateway group will be your good friend, with a well-adjusted load distribution

        you use WAN interfaces with the same name, but their descriptions only are different, so the system use a lower IP address

        Cats bury it so they can't see it!
        (You know what I mean if you have a cat)

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        • D
          dr_tech @DaddyGo
          last edited by

          @DaddyGo said in Multiple Gateways on same subnet:

          you use WAN interfaces with the same name, but their descriptions only are different, so the system use a lower IP address

          Pardon ?

          Gateway groups are also not working in this case, as soon as my primary gateway goes down, I lose connectivity with the Internet.

          1 Reply Last reply Reply Quote 0
          • RicoR
            Rico LAYER 8 Rebel Alliance
            last edited by

            Your windows tracert not showing the pfSense LAN IP as first hop means you have something terribly wrong in your whole setup.

            -Rico

            D 1 Reply Last reply Reply Quote 0
            • D
              dr_tech @Rico
              last edited by

              @Rico said in Multiple Gateways on same subnet:

              Your windows tracert not showing the pfSense LAN IP as first hop means you have something terribly wrong in your whole setup.

              Oh yes, didn't notice that. I'll try setting up pfSense back from scratch and report back.

              DaddyGoD 1 Reply Last reply Reply Quote 0
              • D
                dr_tech
                last edited by

                I re-did all my steps, installing a new pfSense instance, adding a WAN interface with static IP and gateway (10.1.0.1), did a traceroute, all traffic was being routed through the pfSense box :

                10284131-bcde-4120-8996-c2d76d87257a-image.png

                Added a second gateway under System > Routing :

                33aac1c4-29b7-4414-b03b-2d25b03f6dad-image.png

                Modified the default firewall rule to route all traffic through second gateway :
                b3fcd643-6d38-4d22-8903-732bc0c20db2-image.png
                Redid a traceroute :
                7925ffc3-8b7a-466e-86c2-c263d47c235f-image.png
                Everything just breaks apart, NAT stops working, pfSense starts acting sort of like a switch, even when my LAN IP is stil 192.168.1.2/24.

                Please help

                DaddyGoD 1 Reply Last reply Reply Quote 0
                • DaddyGoD
                  DaddyGo @dr_tech
                  last edited by

                  @dr_tech said in Multiple Gateways on same subnet:

                  Oh yes, didn't notice that.

                  this is not entirely the case...
                  only ICMP question, listen....

                  0f8131cd-b72f-42f9-a94c-df990984c39f-image.png

                  Cats bury it so they can't see it!
                  (You know what I mean if you have a cat)

                  1 Reply Last reply Reply Quote 0
                  • DaddyGoD
                    DaddyGo @dr_tech
                    last edited by

                    @dr_tech said in Multiple Gateways on same subnet:

                    Everything just breaks apart, NAT stops working, pfSense starts acting sort of like a switch,

                    there may be serious configuration deficiencies ...
                    I suggest you try to install only one WAN interface first

                    and let us see that this behaves, because basically this is a dual-NAT configuration

                    Cats bury it so they can't see it!
                    (You know what I mean if you have a cat)

                    1 Reply Last reply Reply Quote 0
                    • D
                      dr_tech
                      last edited by

                      @DaddyGo said in Multiple Gateways on same subnet:

                      I suggest you try to install only one WAN interface first

                      I did that, and until that point it works fine. (Pleas refer to my previous post)

                      As soon as I add the second gateway, and set up the firewall rules to divert traffic through the second gateway, I stop seeing the first hop as the IP of pfSense.

                      @dr_tech said in Multiple Gateways on same subnet:

                      all traffic was being routed through the pfSense box :

                      c4782351-7291-4894-bc0f-db61cc6de2ff-image.png

                      (Only the first gateway - 10.1.0.1 Campus Network Installed)

                      DaddyGoD 1 Reply Last reply Reply Quote 0
                      • DaddyGoD
                        DaddyGo @dr_tech
                        last edited by

                        @dr_tech said in Multiple Gateways on same subnet:

                        Pleas refer to my previous post

                        try something please do this:

                        a1475b14-b1b4-4abf-90f8-39e284051576-image.png

                        Cats bury it so they can't see it!
                        (You know what I mean if you have a cat)

                        1 Reply Last reply Reply Quote 0
                        • D
                          dr_tech
                          last edited by

                          @DaddyGo said in Multiple Gateways on same subnet:

                          try something please do this:

                          I have already set it as automatic, the moment I added a second gateway.

                          DaddyGoD 1 Reply Last reply Reply Quote 0
                          • DaddyGoD
                            DaddyGo @dr_tech
                            last edited by DaddyGo

                            @dr_tech

                            What is this.......LAN /16???

                            400f88c9-59a2-44fb-b8d4-4611a27a8a01-image.png

                            +++edit:
                            do you want to say / 24

                            Cats bury it so they can't see it!
                            (You know what I mean if you have a cat)

                            1 Reply Last reply Reply Quote 0
                            • D
                              dr_tech
                              last edited by

                              @DaddyGo said in Multiple Gateways on same subnet:

                              do you want to say / 24

                              No, I meant that the subnet for my LAN is 255.255.0.0, not the default /24 block. But regardless, even if I try the 24 block, I face the same issue.

                              DaddyGoD 1 Reply Last reply Reply Quote 0
                              • DaddyGoD
                                DaddyGo @dr_tech
                                last edited by

                                @dr_tech

                                Ohhh...OK

                                if you think,..... I have a couple of lab pfSense units, I'll try to model your problem tomorrow...
                                we have saturday night at 9pm and my wife is waiting with a bottle of wine...

                                is this right for you?

                                btw:
                                what is a brief description of your hardware?

                                Cats bury it so they can't see it!
                                (You know what I mean if you have a cat)

                                1 Reply Last reply Reply Quote 0
                                • D
                                  dr_tech
                                  last edited by dr_tech

                                  @DaddyGo said in Multiple Gateways on same subnet:

                                  we have saturday night at 9pm

                                  Sure, Have a nice weekend !!

                                  My hardware :
                                  Router 1 (College Router) : Asus RT-AC53 (10.1.0.1)
                                  Router 2 (ISP Router): TP-Link Archer C1200 (10.1.0.2)

                                  pfSense: Running on VMWare ESXi (with an Intel i350-T4 passed through)
                                  Port 1 : Input from Asus RT-AC53
                                  Port 2 : Connected to a Switch (pfSense LAN 192.168.1.0/24)

                                  K 1 Reply Last reply Reply Quote 0
                                  • K
                                    kkrazyken @dr_tech
                                    last edited by

                                    @dr_tech Where is your connection from pfSense to the ISP router?

                                    D 1 Reply Last reply Reply Quote 0
                                    • D
                                      dr_tech
                                      last edited by

                                      This post is deleted!
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                                      • D
                                        dr_tech @kkrazyken
                                        last edited by

                                        @kkrazyken
                                        Router 1 and Router 2 are connected to each other (DHCP turned off on router 2). This was so that I could just switch the gateway address on my phone/laptop to access blocked websites quickly, without changing the network.

                                        That is the reason why Router 1 is at 10.1.0.1/16 and Router 2 at 10.1.0.2/16.

                                        K 1 Reply Last reply Reply Quote 0
                                        • K
                                          kkrazyken @dr_tech
                                          last edited by

                                          @dr_tech I see, two Gateways on the same WAN interface. On the WAN interface page, what is the GW set to there? Does changing it make a difference?

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                                          • JeGrJ
                                            JeGr LAYER 8 Moderator
                                            last edited by

                                            As @johnpoz likes to say, that setup is bonkers ;)

                                            Yes you can use multiple gateways on a single WAN that's right, but it makes things complicated, as PF rules are setup to e.g. reply on the interface. But reply-to whom? The GW that is set up with the WAN IF is used primarily for many thing. If that's not the wanted you have to get those two Gateways to separate interfaces and add a second WAN interface to properly use MultiWAN the right way. Why are both gateways in the same subnet anyways? Is that necessary for anyone?

                                            I'd change the IP of the second WAN (the ISP one) and set it up as an additional WAN(2). That way all routing and forwarding functionality can work the right way right from the start including Gateway Groups or port forwardings that otherwise are hard to make work.

                                            Don't forget to upvote 👍 those who kindly offered their time and brainpower to help you!

                                            If you're interested, I'm available to discuss details of German-speaking paid support (for companies) if needed.

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