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    Comcast ipv6 / Netgear C7100V

    Scheduled Pinned Locked Moved IPv6
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    • JKnottJ
      JKnott @rdunkle
      last edited by

      @rdunkle

      Do they use DHCPv6-PD? That's the typical way an ISP provides IPv6. Did you have IPv6 with the old modem? Is pfSense configured for DHCPv6-PD?

      Is there a Comcast user forum that can help?

      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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      • johnpozJ
        johnpoz LAYER 8 Global Moderator
        last edited by

        If you have the device in bridge mode, and you had connected your pc... And then you connected pfsense - you would of needed to power cycle the netgear "modem" (Not really its a gateway - modem/router combo)

        Pretty much any cable modem will pair with the mac it sees connected.. And to clear that you will need to power cycle it before you connect a different device.

        Or! your new device you connect needs to "clone" the mac of the previous device..

        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 24.11 | Lab VMs 2.8, 24.11

        N 1 Reply Last reply Reply Quote 1
        • N
          Napsterbater @johnpoz
          last edited by

          @johnpoz said in Comcast ipv6 / Netgear C7100V:

          If you have the device in bridge mode, and you had connected your pc... And then you connected pfsense - you would of needed to power cycle the netgear "modem" (Not really its a gateway - modem/router combo)

          Pretty much any cable modem will pair with the mac it sees connected.. And to clear that you will need to power cycle it before you connect a different device.

          Or! your new device you connect needs to "clone" the mac of the previous device..

          Cloning should (keyword) not be necessary, but I bet a power cycle with ONLY pfSense's WAN connected wold have worked.

          Getting bridge mode working would be a MUCH better/cleaner setup.

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          • johnpozJ
            johnpoz LAYER 8 Global Moderator
            last edited by

            @Napsterbater said in Comcast ipv6 / Netgear C7100V:

            Cloning should (keyword) not be necessary

            Completely agree.. Shoudn't be needed - but I use to when running pfsense as VM, use the technique so that I could bring up different pfsense snapshot versions on different vms, or even other router distro's to play without getting a different IP or having to power cycle the modem.. But I would just set the mac on the vm nic to be the same vs using any "cloning" feature in pfsense for example.

            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 24.11 | Lab VMs 2.8, 24.11

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            • rdunkleR
              rdunkle
              last edited by

              The old modem never had ipv6 support.

              PFsense is configured on the wan with:
              -IPV6 configuration type: dhcp6
              -Use ipv4 connectivity as parent interface
              -DHCPv6 prefix delegation size 60
              -Send an ipv6 prefix hint
              I am able to get an ipv6 address only when pfsense wan is put in the Netgear DMZ
              .
              What mac address would I possibly need to clone?
              When the modem is in bridge mode it still is using the CM Mac address.

              Another question.
              When this Netgear C7100 is in bridge mode you can start to administer it on ip address 192.168.10.1. I figured if the modem is in bridge mode it becomes completely dumb. But that is not the case, as you still can access the web ui on 192.168.10.1.

              I am remote from the site for a week. I will give these suggestions a try when I can get back.

              Thanks everyone!

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              • N
                Napsterbater @rdunkle
                last edited by Napsterbater

                @rdunkle said in Comcast ipv6 / Netgear C7100V:

                Another question.
                When this Netgear C7100 is in bridge mode you can start to administer it on ip address 192.168.10.1. I figured if the modem is in bridge mode it becomes completely dumb. But that is not the case, as you still can access the web ui on 192.168.10.1.

                I am remote from the site for a week. I will give these suggestions a try when I can get back.

                Thanks everyone!

                Just because you can access the modem via that IP address does not mean the modem is not in true bridge mode. Cable modems have long been able to be accessed via a particular IP most notably the old surfboard modems but pretty much all of them can be from some particular IP.

                @rdunkle said in Comcast ipv6 / Netgear C7100V:

                What mac address would I possibly need to clone?
                When the modem is in bridge mode it still is using the CM Mac address.

                Ignore cloning for the time being. I am pretty much definite on that not be needed. What you do need to do though. Is put the modem in bridge mode and then once it's rebooted assuming it's going to reboot on its own pull the power plug from the modem completely wait 5 seconds and then start it back up with it now plugged into your pfSense WAN.

                In bridge mode the modem will only allow a certain amount of Mac addresses to be bound to the bridge and cross the bridge. If you boot the modem up plugged into your personal computer and then try to plug in pfSense you will hit the limit of one that is likely on your account. So anytime you switch devices you must power off the modem completely plug it into your new device and then power back up.

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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by

                  @Napsterbater said in Comcast ipv6 / Netgear C7100V:

                  I am pretty much definite on that not be needed.

                  Never said it was... My point is if you change the device connected to the modem, your going to want to power cycle the modem before you connect a new device.

                  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 24.11 | Lab VMs 2.8, 24.11

                  N 1 Reply Last reply Reply Quote 1
                  • N
                    Napsterbater @johnpoz
                    last edited by

                    @johnpoz said in Comcast ipv6 / Netgear C7100V:

                    @Napsterbater said in Comcast ipv6 / Netgear C7100V:

                    I am pretty much definite on that not be needed.

                    Never said it was... My point is if you change the device connected to the modem, your going to want to power cycle the modem before you connect a new device.

                    Op mentioned it again, was in reply to Op. Edited post to clarify

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                    • rdunkleR
                      rdunkle
                      last edited by

                      I got some remote hands on the modem. I set the modem to "Router mode" No. The Netgear then updated the settings and rebooted. I waited about 5 minutes. Then I powered off the Netgear. The PFSense machine was still wired to the modem. I waited ~ 30 seconds. Then powered up the Netgear.

                      The PFSense picked up a WAN ipv4 and ipv6. The LAN picked up an ip6 address. Clients on the LAN have functional ipv6 and ipv4.

                      So, just like you told me the important step was to power off the modem. I did not clone any MAC address, just went with what it had.

                      I can still log into the Netgear on 192.168.100.1, but the functions and menu are slim. There is not even a choice to update the administrator password.

                      I have some questions about ipv6 LAN - track interface and about ipv6 WAN prefix delegation, but I will start another thread for those questions.

                      Thank you for the correct solution.

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                      • johnpozJ
                        johnpoz LAYER 8 Global Moderator
                        last edited by johnpoz

                        @rdunkle said in Comcast ipv6 / Netgear C7100V:

                        I did not clone any MAC address, just went with what it had.

                        I am thinking my mention of cloning mac address might of muddled the conversation... This is an option for when you want to change devices and not power cycle a modem..

                        I use to do this when I wanted to fire up a different router distro most of the time on a vm.. So that my public IP wouldn't change.. And allowed me to switch between distros faster without having to wait for the modem to power cycle as well.

                        It for sure is an "option" if you do not have an easy method of power cycle the modem, or not enough time to wait for it, etc. etc.. Prob the only option you will have once you place a modem in bridge vs router mode would be to switch it back to router mode.. I hit the 192.168.100.1 address to view "status" of my cable modem for example.. Which doesn't even have a router mode.

                        Glad you got it all sorted.

                        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 24.11 | Lab VMs 2.8, 24.11

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