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    Mapping ISP provided Static IP to MAC addresses -behind Pfsense

    Scheduled Pinned Locked Moved General pfSense Questions
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    • JKnottJ
      JKnott @ros81
      last edited by

      @ros81

      Normally, IPv6 uses the DUID for that. Also, are they providing addresses for each host? Or just a prefix and letting you manage your hosts? I'm on Rogers and get a /56 prefix from them. With the DUID, my prefix is unlikely to change, but Rogers knows nothing about what's behind my firewall. Also, MAC addresses are irrelevant off the local network, as they don't pass through the firewall. So, even if they were using the MAC to assign an address, they'd never see it.

      Are they providing a prefix? Or just a single address?

      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...

      R 1 Reply Last reply Reply Quote 0
      • R
        ros81 @JKnott
        last edited by

        @JKnott Thanks for your reply.. Its a /24. But they are enabling 1 IP per Mac address provided.

        So my question is will NAT work for Port forwarding from the WAN, if the ISP can't see the MAC Address.?

        R JKnottJ 2 Replies Last reply Reply Quote 0
        • R
          ros81 @ros81
          last edited by

          @ros81 to answer your question... they are providing addresses for each host. Anyway to map this in Pfsense?

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          • R
            ros81
            last edited by

            Would NAT 1:1 on Pfsense help? Mind it the VoIP server is not on a DMZ.

            1 Reply Last reply Reply Quote 0
            • JKnottJ
              JKnott @ros81
              last edited by

              @ros81

              Why did I think IPv6 was involved? Anyway, the router part still stands. If you have a router, such as pfSense, they'll never see the MAC. There are firewalls that act like a bridge, but I don't know if pfSense can do that.

              BTW, Telus also provides IPv6, so you'll want to consider that too, when you set up the firewall.

              Also, please, Please, PLEASE learn to forget about NAT. It's a curse on networks that came about due to the IPv4 address shortage. As I mentioned, the proper solution is a firewall that filters without routing. With NAT, they'll only see a single MAC, that of the firewall WAN NIC, for every device behind it.

              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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              • R
                ros81
                last edited by

                Thanks @JKnott
                But I guess I need to use NAT as I'm working with 2 public IPs . One for the Pfsense box that is connected to the ISP bridged modem/router , and the other is the non-DMZ Voice server.
                I just want to find the best method to implement proper NAT to external IPs, on the pfsense.

                JKnottJ 1 Reply Last reply Reply Quote 0
                • JKnottJ
                  JKnott @ros81
                  last edited by JKnott

                  @ros81

                  You're still down to 1 MAC, which means you'll only get one IP. What are the servers running on? If Linux, you've already got a good firewall there. Linux is used in most of the consumer grade firewalls out there and some form of Unix on just about everything else. Even some Cisco gear runs on Linux.

                  I really wish people would forget about NAT, as it causes them to come up with poor solutions, instead of doing it the proper way. What you need is a firewall that will filter without routing and passes packets intact, complete with original MAC.

                  BTW, before switching to pfSense, I used Linux for my firewall.

                  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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                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by

                    Can they use the same MAC for both IPs? That is a very common setup. In that case you could 1:1 NAT it from a virtual IP on WAN to the VoIP server on an internal subnet.

                    Otherwise to use the IP directly and get the MAC from the server you would have to bridge it's interface to the WAN. To do that you would need to have a NIC available to use.

                    Steve

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                    • JKnottJ
                      JKnott
                      last edited by

                      @stephenw10 said in Mapping ISP provided Static IP to MAC addresses -behind Pfsense:

                      Can they use the same MAC for both IPs?

                      If he used a static config, he could use aliases. However, I thought he had to provide the MAC to Telus, which means they'd be using a DHCP server with static mapping. Try assigning 2 IPs to a MAC in pfSense and see what happens. Hint - It's not allowed.

                      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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                      • R
                        ros81
                        last edited by

                        Thanks @stephenw10 and @JKnott

                        1. You are right... ISP does not allow to use the same MAC for both IPs. I'm trying to get this escalated in TELUS.

                        2. WAN router is bridged to PFSense box.

                        3. I was reading about creating virtual IPs in Pfsense for the non-DMZ server public IP and then create NAT 1:1... I'll be testing in a few hours. Hopefully, it works. Let me know any suggestions.

                        JKnottJ 1 Reply Last reply Reply Quote 0
                        • stephenw10S
                          stephenw10 Netgate Administrator
                          last edited by

                          If you need two MACs you will have to bridge the WAN with another NIC so the server pulls the IP from Telus directly.
                          Is that an option for you? You have a NIC you can use to connect the server?

                          You can still filter traffic across the bridge.

                          There is also at least one truly horrendous hack you might deploy if all else fails. 😉

                          Steve

                          R 1 Reply Last reply Reply Quote 0
                          • R
                            ros81
                            last edited by

                            Guess there are more people asking the same question, and they are on TELUS...
                            https://www.reddit.com/r/networking/comments/4u3sn3/isp_delivers_static_ips_via_dhcp_reservation/

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                            • R
                              ros81 @stephenw10
                              last edited by ros81

                              @stephenw10 I want to keep the server behind the Pfsense. So I'm not sure how to achieve what you are suggesting.

                              WAN (Public IP1) --Bridged--> PFSense (with VLANs) -> switches and server(on vlan).
                              Public IP2 for the server.

                              How do I associate Public IP2 to the server, since the public IP2 requires DHCP reservation for the server.

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                              • JKnottJ
                                JKnott @ros81
                                last edited by

                                @ros81 said in Mapping ISP provided Static IP to MAC addresses -behind Pfsense:

                                I was reading about creating virtual IPs in Pfsense for the non-DMZ server public IP and then create NAT 1:1... I'll be testing in a few hours. Hopefully, it works. Let me know any suggestions.

                                Please forget NAT. It's a borked solution, as johnpos would say. Here's some info on setting up pfSense as a transparent firewall. This is the sort of solution you need, not NAT.

                                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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                                • stephenw10S
                                  stephenw10 Netgate Administrator
                                  last edited by

                                  Do you have an additional interface on pfSense you can use for this?

                                  Or is the server on a separate VLAN? Could it be?

                                  The best solution for you here is to put the server in a a sort of DMZ bridged to the WAN. So:

                                  WAN (Public IP1)--> PFSense (with VLANs) -> switches - LAN clients
                                                        |
                                                        |_ Voip server (Public IP2)
                                  

                                  The VoIP server is set as DHCP and pulls it's IP from Telus directly.

                                  Steve

                                  R 1 Reply Last reply Reply Quote 0
                                  • R
                                    ros81 @stephenw10
                                    last edited by

                                    @stephenw10 Thanks... The server is on a separate VLAN.
                                    Are you suggesting to do this?

                                    202e11f4-67c7-4401-9559-d98f9bc5e758-image.png

                                    Or this diagram...
                                    106eb183-2123-4c33-a81d-c644b1151403-image.png

                                    If diagram 2, can the ISP see the MAC address on the other NIC card in the PFsense box?

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                                    • R
                                      ros81
                                      last edited by

                                      Either way, I don't feel comfortable to leave the Voice Server on DMZ. Thanks guys for your suggestions, but do you have any other suggestions?

                                      JKnottJ 1 Reply Last reply Reply Quote 0
                                      • JKnottJ
                                        JKnott @ros81
                                        last edited by

                                        @ros81 said in Mapping ISP provided Static IP to MAC addresses -behind Pfsense:

                                        Thanks guys for your suggestions, but do you have any other suggestions?

                                        Only the correct one, that is a transparent firewall, as I suggested. I provided a link to that pfSense article for doing that. With it, Telus will be able to assign IP addresses to the MAC addresses, as required.

                                        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...

                                        1 Reply Last reply Reply Quote 0
                                        • stephenw10S
                                          stephenw10 Netgate Administrator
                                          last edited by stephenw10

                                          It would be like the 2nd diagram. You would set the server VLAN interface as IPv4 type none then create a bridge with it and WAN in.

                                          Now it's in the same layer 2 segment as the WAN so can pull an IP directly from Telus using it's own MAC.

                                          I'm not sure why you would not want to do that. You can still filter all the incoming and outgoing traffic to it.

                                          The other suggestions I have are last ditch style. Do you have a spare NIC you can use in that system?

                                          Steve

                                          R 1 Reply Last reply Reply Quote 0
                                          • R
                                            ros81 @stephenw10
                                            last edited by

                                            @stephenw10 Thanks.. I like your idea about the diagram 2..(You said this can be achieved without an additional NIC card, but just with vlan.) Can you explain how to do it ?
                                            I have another NIC too..

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