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    2 Separate pfSense sharing same WAN subnet

    Scheduled Pinned Locked Moved Routing and Multi WAN
    11 Posts 2 Posters 766 Views 2 Watching
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    • johnpozJ Offline
      johnpoz LAYER 8 Global Moderator @itsystemsllc
      last edited by

      Well sniff on pfsense2 wan then you try and access its wan IP from pfsense1 - do you see that traffic get there?

      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 25.07 | Lab VMs 2.8, 25.07

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      • I Offline
        itsystemsllc
        last edited by

        @johnpoz I forgot to mention that when I ping pfsense1 from the LAN side of pfsense2 I do get a reply. This works vice versa as well.

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        • I Offline
          itsystemsllc
          last edited by itsystemsllc

          This is a packet capture from pfsense1 while it is trying to reach pfsense2 in a browser https://1.2.3.92:10000 (10000 the port I use for remote management).
          11:53:47.206735 IP 1.2.3.92.10000 > 1.2.3.90.9922: tcp 0
          11:53:47.206825 IP 1.2.3.90.46824 > 1.2.3.92.10000: tcp 0
          11:53:47.206949 IP 1.2.3.90.9922 > 1.2.3.92.10000: tcp 0
          11:53:47.427922 IP 1.2.3.90.9922 > 1.2.3.92.10000: tcp 517
          11:53:47.427954 IP 1.2.3.90.46824 > 1.2.3.92.10000: tcp 517
          11:53:48.706584 IP 1.2.3.90.46824 > 1.2.3.92.10000: tcp 517
          11:53:48.709737 IP 1.2.3.90.9922 > 1.2.3.92.10000: tcp 517
          11:53:49.412252 IP 1.2.3.92.10000 > 1.2.3.90.9922: tcp 0
          11:53:49.412294 IP 1.2.3.92.10000 > 1.2.3.90.46824: tcp 0
          11:53:49.412411 IP 1.2.3.90.46824 > 1.2.3.92.10000: tcp 0
          11:53:49.412414 IP 1.2.3.90.9922 > 1.2.3.92.10000: tcp 0
          11:53:51.270594 IP 1.2.3.90.9922 > 1.2.3.92.10000: tcp 517
          11:53:51.272548 IP 1.2.3.90.46824 > 1.2.3.92.10000: tcp 517
          11:53:53.623438 IP 1.2.3.92.10000 > 1.2.3.90.46824: tcp 0
          11:53:53.623480 IP 1.2.3.92.10000 > 1.2.3.90.9922: tcp 0
          11:53:53.623748 IP 1.2.3.90.46824 > 1.2.3.92.10000: tcp 0
          11:53:53.623751 IP 1.2.3.90.9922 > 1.2.3.92.10000: tcp 0
          11:53:56.388068 IP 1.2.3.90.46824 > 1.2.3.92.10000: tcp 517
          11:53:56.390001 IP 1.2.3.90.9922 > 1.2.3.92.10000: tcp 517

          Here is the packet capture from the pfsense2 side during the same process
          11:54:53.485205 IP 1.2.3.90.18387 > 1.2.3.92.10000: tcp 0
          11:54:53.485249 IP 1.2.3.92.10000 > 1.2.3.90.18387: tcp 0
          11:54:53.486255 IP 1.2.3.90.45498 > 1.2.3.92.10000: tcp 0
          11:54:53.486289 IP 1.2.3.92.10000 > 1.2.3.90.45498: tcp 0
          11:54:54.487870 IP 1.2.3.92.10000 > 1.2.3.90.45498: tcp 0
          11:54:54.487879 IP 1.2.3.92.10000 > 1.2.3.90.18387: tcp 0
          11:54:56.704054 IP 1.2.3.92.10000 > 1.2.3.90.18387: tcp 0
          11:54:56.704062 IP 1.2.3.92.10000 > 1.2.3.90.45498: tcp 0
          11:55:00.951058 IP 1.2.3.92.10000 > 1.2.3.90.45498: tcp 0
          11:55:00.951066 IP 1.2.3.92.10000 > 1.2.3.90.18387: tcp 0

          (obviously I've edited these logs with the fake IPs!)

          When I run the process the other way, trying to access the web interface of pfsense1 on port 10000 from behind pfsense2, the results are the same just reversed.

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          • johnpozJ Offline
            johnpoz LAYER 8 Global Moderator @itsystemsllc
            last edited by

            well that doesn't make any sense then. Pfsense doesn't care if the source IP is on its wan network or some other public IP, etc.

            The process would be exactly the same. So your saying it works from IP 1.2.3.4 but not 4.5.6.7 which if you have connectivity pfsense wouldn't care. What the source IP is.

            Your sure its not a resolution issue?

            These are different boxes - and not 2 vms say on the same host using the same nic for their wan?

            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 25.07 | Lab VMs 2.8, 25.07

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            • I Offline
              itsystemsllc
              last edited by

              @johnpoz these are 2 separate physical boxes. The only connection between them is that they are connected to the same cable modem.

              I'm not sure what you mean by this: " So your saying it works from IP 1.2.3.4 but not 4.5.6.7" ?

              I can access the web interface and other NAT'd services that are available on either pfsense1 or pfsense2 if I am coming to them from ANY other network just not when I hit pfsense1 from pfsense2 or 2 from 1.

              When you say resolution, are you referring to DNS? I'm using the IPs when I try to make these connections so DNS shouldn't be an issue.

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

                @itsystemsllc said in 2 Separate pfSense sharing same WAN subnet:

                they are connected to the same cable modem.

                Cable "modems" don't have multiple lan ports that I am aware of.. What is the make and model of this device? Some sort of gateway device..

                is it doing some sort of odd passthru to give pfsense their public wan IPs?

                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 25.07 | Lab VMs 2.8, 25.07

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                • I Offline
                  itsystemsllc
                  last edited by

                  @johnpoz cable modems for business class connections with more than 1 static IP have a 4 port switch in them.

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                  • johnpozJ Offline
                    johnpoz LAYER 8 Global Moderator @itsystemsllc
                    last edited by

                    And those are not "modems" those are gateways.. I have a few of those in a few different offices..

                    And they can do all kinds of odd stuff where the public IP is passed through it via a mac, etc. And some ports can be set to get a public IP, and others in the switch ports can be natted, etc.

                    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 25.07 | Lab VMs 2.8, 25.07

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                    • I Offline
                      itsystemsllc
                      last edited by

                      @johnpoz - A "business gateway" is also a modem. It has a coax connection and 4 port switch. Modem means modulate/demodulate which is the process of converting from coax to ethernet and vice versa. So, yes, it is a modem LOL

                      I am not using any of the router or firewall functions that are sometimes included in a modem/gateway. Generally speaking these devices will automatically bridge the traffic when a static public IP address is assigned to customer equipment. Thus rendering any router or firewall on the ISP device moot. I don't have issues with access to private NAT'd services from the Internet into the aforementioned networks so I don't believe that the modem is interfering with any of that because it is bridging the connection.

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                      • johnpozJ Offline
                        johnpoz LAYER 8 Global Moderator @itsystemsllc
                        last edited by johnpoz

                        Didn't say it didn't have a "modem" in it.. But that is a horrible term to use for something that is more than a modem.. Its not a "modem" its a gateway..

                        Sniff on pfsense2 wan when you try to access one of your forwarded ports from pfsense1 - do you see the traffic? If so then it would work. Just like any other port forward.

                        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 25.07 | Lab VMs 2.8, 25.07

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