Netgate Discussion Forum
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Search
    • Register
    • Login

    Switched to AT&T fiber, IPv6 tunnel broken

    Scheduled Pinned Locked Moved General pfSense Questions
    29 Posts 5 Posters 283 Views 4 Watching
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • JKnottJ Offline
      JKnott @BiloxiGeek
      last edited by

      @BiloxiGeek said in Switched to AT&T fiber, IPv6 tunnel broken:

      But since it's AT&T I suspect they are gonna want to charge me extra for the additional service.

      I bet it's already available. With my ISP, I just had to enable it and it works. Configure pfSense for IPv6 and see what happens.

      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
      • JKnottJ Offline
        JKnott @johnpoz
        last edited by

        @johnpoz said in Switched to AT&T fiber, IPv6 tunnel broken:

        I thought back when they first rolled out ipv6 they were using 6rd and were blocking 41 because they were using it

        My ISP was offering 6to4 and 6rd before going native. I had no problem using 6in4, back then. There should have been no conflict with protocol 41.

        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...

        johnpozJ 1 Reply Last reply Reply Quote 0
        • JKnottJ Offline
          JKnott @johnpoz
          last edited by

          @johnpoz said in Switched to AT&T fiber, IPv6 tunnel broken:

          I would think putting it into bridge mode would disable any sort of firewalling

          Given the firewall in those modems, is that a bad thing? 😉

          Since this is a pfSense forum, I expect people here will be running pfSense for their 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...

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

            @JKnott said in Switched to AT&T fiber, IPv6 tunnel broken:

            There should have been no conflict with protocol 41.

            I agree - just what I read some places, doesn't mean its true. Some thread somehwere was stated that att was blocking protocol 41 for anything other than their network, and when they moved to dual stack vs 6rd for their IPv6 rollout they remove the 41 block.

            I am leaning towards the disable ipv6 in his att device to be honest, since if you are using the device as passthru and wanted to disable IPv6 blocking protocol 41 would be a way to stop a client connected from creating a tunnel and using IPv6 that way, 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 25.07.1 | Lab VMs 2.8, 25.07.1

            1 Reply Last reply Reply Quote 0
            • BiloxiGeekB Offline
              BiloxiGeek
              last edited by

              Is there a difference between bridge mode and passthrough? I've set passthrough already and didn't get the tunnel up. If there's a separate bridge mode I'm more than willing to give it a try but I've not seen that setting anywhere in the BGW320 config.

              And I too would prefer to deal with any latency issues in order to keep the 6in4 tunnel with the known and expected addresses.

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

                @BiloxiGeek that might what its called on that device, can you enable IPv6 and leave it passthru?

                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 25.07.1 | Lab VMs 2.8, 25.07.1

                M 1 Reply Last reply Reply Quote 0
                • M Offline
                  marcg @johnpoz
                  last edited by

                  @johnpoz There's no true bridge mode on the BGW320 AFAIK. IP Passthrough is bridge-like, but is NAT under the hood. With Passthrough enabled and v6 disabled on the BGW LAN side, I could see how that might prevent ATT's native v6 from working. Disabling v6 might prevent the Passthrough v6 NAT states from being created.

                  @BiloxiGeek, if you haven't already done so, suggest that the BGW's Passthrough Mode be configured as DHCPS-Fixed with the pfSense WAN MAC entered as the Passthrough Fixed MAC Address. If there's ever more than one device on the BGW's LAN side -- wired or wireless -- at boot time, the DHCPS-Dynamic option will cause the BGW to pick whichever device it sees first as the passthrough client, not necessarily pfSense (probably not what you want).

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

                    @marcg said in Switched to AT&T fiber, IPv6 tunnel broken:

                    isabling v6 might prevent the Passthrough v6 NAT states from being created.

                    concur - I do believe that is his problem.. I don't think those devices do a true bridge, more like a nat with with dmz host sort of thing.

                    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 25.07.1 | Lab VMs 2.8, 25.07.1

                    M 1 Reply Last reply Reply Quote 0
                    • M Offline
                      marcg @johnpoz
                      last edited by marcg

                      @johnpoz said in Switched to AT&T fiber, IPv6 tunnel broken:

                      I don't think those devices do a true bridge, more like a nat with with dmz host sort of thing.

                      It's similar, but different. In Passthrough mode, pfSense gets the public v4 IP of the BGW. For v6, the pfSense gets a routeable IP via DHCP for its WAN IP, and any delegated prefixes that it requests. pfSense thinks that it's directly on the WAN with routeable addresses and prefixes.

                      The BGW then 1:1 NATs every flow to/from pfSense, keeping the same source/destination address/port on both sides of the NAT. There's a snippet from the BGW's NAT table below. The x's are to obscure my routeable addresses and prefixes.

                      Guessing one reason they don't do a true bridge is to enable the BGW to NAT+route in parallel for its non-Passthrough LAN-side clients (none in my case).

                      Screenshot 2025-09-01 173933.png

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

                        @marcg well that is good, then it should work for the OP.

                        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 25.07.1 | Lab VMs 2.8, 25.07.1

                        1 Reply Last reply Reply Quote 0
                        • First post
                          Last post
                        Copyright 2025 Rubicon Communications LLC (Netgate). All rights reserved.