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    Enabling IPv6 on Comcast home network

    Scheduled Pinned Locked Moved IPv6
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator @lenhuppe
      last edited by johnpoz

      But did you actually get a prefix that you requested? There are some threads around here talking about how to troubleshoot that.. @JKnott prob the guy you want to help with this.. He loves IPv6 ;) My advice would be to just turn it off.. Or just run a HE tunnel.

      They will give you a free /48 and you can take it with you if you change ISPs.. They allow for PTR settings on the IPv6 addresses, etc. Many reasons why its just easier than dealing with some lack luster isp IPv6 deployments.

      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

      L JKnottJ 3 Replies Last reply Reply Quote 0
      • JKnottJ
        JKnott @johnpoz
        last edited by

        @johnpoz said in Enabling IPv6 on Comcast home network:

        Guy you want for ipv6 stuff around here is @JKnott - can't believe he hasn't chimed in already.. Its been 10 minutes since you mentioned IPv6 ;) heheheh

        I just got here. It took me a while to find a phone booth, so I could change into my uniform. Phone booths are getting scarce these days. 😉

        While I am good with IPv6, I have no experience with Comcast. However, I assume they use DHCPv6-PD, like many other providers.

        As for getting IPv6, it's entirely possible to plug a computer directly into a modem in bridge mode and get an address for that computer. I've done that here many times and it's how pfsense would get it's WAN address.

        @lenhuppe Can you show your configuation, so I know what you've done? I'll need both WAN and LAN configurations.

        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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        • JKnottJ
          JKnott @lenhuppe
          last edited by

          @lenhuppe said in Enabling IPv6 on Comcast home network:

          I have Comcast and a rented cable modem.

          Is the modem in bridge or gateway mode? You want bridge mode.

          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...

          L 2 Replies Last reply Reply Quote 0
          • L
            lenhuppe @johnpoz
            last edited by

            @johnpoz said in Enabling IPv6 on Comcast home network:

            HE tunnel

            There are at least two places where I can enter a prefix. The "DHCPv6 Prefix Delegation size" defaults to 64 on the WAN side and the "IPv6 Prefix ID" defaults to 0 on the LAN side.

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

              @johnpoz said in Enabling IPv6 on Comcast home network:

              But did you actually get a prefix that you requested?

              One thing that can be done is run a packet capture on boot up, to see what's being provided. To do that:

              Shut down pfsense and disconnect the WAN cable
              Reboot pfsense and start Packet Capture, filtering on port 546
              Reconnect the WAN cable
              Post the capture file here.

              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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              • L
                lenhuppe @JKnott
                last edited by

                @jknott said in Enabling IPv6 on Comcast home network:

                @lenhuppe said in Enabling IPv6 on Comcast home network:

                I have Comcast and a rented cable modem.

                Is the modem in bridge or gateway mode? You want bridge mode.

                I should contact Comcast and tell them I need to access the cable modem. The last time I tried that they gave me hard time. Comcast is a terrible company and even worse ISP.

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

                  @lenhuppe said in Enabling IPv6 on Comcast home network:

                  The "DHCPv6 Prefix Delegation size" defaults to 64 on the WAN side and the "IPv6 Prefix ID" defaults to 0 on the LAN side.

                  The proper value depends on what prefix size they provide. For example, I get a /56 from my provider. The prefix ID is used to select which /64 from your prefix you want to use on an interface.

                  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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                  • JKnottJ
                    JKnott @lenhuppe
                    last edited by

                    @lenhuppe

                    You might be able to do that yourself. Post the make and model here and perhaps someone knows. Otherwise, a search on the net may provide the info.

                    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...

                    L 1 Reply Last reply Reply Quote 0
                    • L
                      lenhuppe @JKnott
                      last edited by lenhuppe

                      @jknott said in Enabling IPv6 on Comcast home network:

                      @lenhuppe

                      You might be able to do that yourself. Post the make and model here and perhaps someone knows. Otherwise, a search on the net may provide the info.

                      I have accessed the cable modem and found the "Delegated prefix" number. Its an Xfinity CGM4140COM if that helps at all. I just need to know where to enter the prefix.

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

                        @jknott said in Enabling IPv6 on Comcast home network:

                        @lenhuppe said in Enabling IPv6 on Comcast home network:

                        I have Comcast and a rented cable modem.

                        Is the modem in bridge or gateway mode? You want bridge mode.

                        If I try to enable bridge mode it warns that wifi will not work in bridge mode. I need wifi so I can't switch to bridge.

                        JKnottJ 1 Reply Last reply Reply Quote 0
                        • L
                          lenhuppe @johnpoz
                          last edited by

                          @johnpoz said in Enabling IPv6 on Comcast home network:

                          But did you actually get a prefix that you requested? There are some threads around here talking about how to troubleshoot that.. @JKnott prob the guy you want to help with this.. He loves IPv6 ;) My advice would be to just turn it off.. Or just run a HE tunnel.

                          They will give you a free /48 and you can take it with you if you change ISPs.. They allow for PTR settings on the IPv6 addresses, etc. Many reasons why its just easier than dealing with some lack luster isp IPv6 deployments.

                          On the WAN side DHCPv6 Prefix Delegation size is set to 64 and the the router has a delegation prefix ending in ::64 so I think that I am getting the /64 prefix as requested.

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                          • JKnottJ
                            JKnott @lenhuppe
                            last edited by

                            @lenhuppe

                            If you're not in bridge mode, you will only be able to get a single /64, which pfsense cannot split among your LAN interfaces. Here I have a modem that includes home phone and I also have IPTV. Instead of using the built in WiFi, I have a separate access point, which is mounted roughly in the middle of my condo. Bridge mode had no effect on my home phone or IPTV.

                            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 L 2 Replies Last reply Reply Quote 0
                            • johnpozJ
                              johnpoz LAYER 8 Global Moderator @JKnott
                              last edited by johnpoz

                              So NOT a modem - but a gateway... Which is why I asked for model...

                              Yeah its not going to work with one of their shitty gateways. I should of known that as soon as you said rent - they don't rent modems any more, only gateway.. Back in the day they just gave you a modem..

                              Get yourself a MODEM.. and then an AP and save yourself some money in the long vs paying them rent for the hardware.

                              Or - just use HE for ipv6... But you still going to have issues with your wifi stuff off their gateway and then stuff behind pfsense.

                              If your going to use pfsense - all you want is modem.. Get a docsis 3.1, maybe even one the new ones with 2.5gbps interfaces to future proof yourself when you want over 1gig internet.

                              How much are they raping you on rent? $10 a month.. Depending on what you get you could break even on the rent in a year or so and then anything after that is just saved money..

                              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

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

                                @johnpoz said in Enabling IPv6 on Comcast home network:

                                So NOT a modem - but a gateway... Which is why I asked for model...

                                Well, the box I got from my ISP can be configured as a modem (in bridged mode) or gateway. What would you call it. It's been a long time since my ISP provided a plain modem. Even back around 2008 or so, it was difficult to get the local phone company to provide a basic ADSL modem. You had to get their gateway and configure it for bridge mode. And that was for business customers.

                                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
                                • johnpozJ
                                  johnpoz LAYER 8 Global Moderator @JKnott
                                  last edited by johnpoz

                                  While yes some gateways can be put into bridge mode - but as he mentioned that kills his wifi. But as soon as he said rent I should of know why it wasn't working is because he was already behind a nat, etc.

                                  If he had just actual modem - would of worked right out of the box pretty much.

                                  I specifically asked right up front

                                  Is there some isp router in front of pfsense? Or just a cable modem - what is the device your plugging pfsense into?

                                  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

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

                                    @johnpoz said in Enabling IPv6 on Comcast home network:

                                    but as he mentioned that kills his wifi

                                    Mine too. When it's in bridge mode, all I get is the modem function.

                                    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
                                    • johnpozJ
                                      johnpoz LAYER 8 Global Moderator @JKnott
                                      last edited by johnpoz

                                      @jknott said in Enabling IPv6 on Comcast home network:

                                      all I get is the modem function.

                                      Are you paying the isp for this device? Not sure why I would have a gateway device if all I am going to do is use it in modem mode.. I sure and the hell would not pay any sort of fee or rent to have this device from the ISP when I can buy a perfectly good "modem" that should last 3-5 years.. Way longer than needed to pay for itself vs rental fees to isp.

                                      Just looked current "modem" I get back in sept 2017.. Cost me $110 rounded up... If would of been paying rent I would be at like $460 spent so far.. So looked I saved $350 to date.. Prob get another year out of it if not longer.. Only reason really would change it out is I increased isp speed and needed docsis 3.1. Or if it fails - which it has already paid for itself twice over.

                                      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

                                      L JKnottJ 2 Replies Last reply Reply Quote 0
                                      • L
                                        lenhuppe @johnpoz
                                        last edited by

                                        @johnpoz said in Enabling IPv6 on Comcast home network:

                                        @jknott said in Enabling IPv6 on Comcast home network:

                                        all I get is the modem function.

                                        Are you paying the isp for this device? Not sure why I would have a gateway device if all I am going to do is use it in modem mode.. I sure and the hell would not pay any sort of fee or rent to have this device from the ISP when I can buy a perfectly good "modem" that should last 3-5 years.. Way longer than needed to pay for itself vs rental fees to isp.

                                        This is at a shared residence and yes the router is rented. I am going to the xfinity store to change the account asap. The last time I checked there was exactly one choice of modem that worked with comcast. That was a while ago so hopefully there are better choices nowadays.

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                                        • JKnottJ
                                          JKnott @johnpoz
                                          last edited by JKnott

                                          @johnpoz said in Enabling IPv6 on Comcast home network:

                                          Are you paying the isp for this device?

                                          It is supplied by them and is included in the cost of the service. It also includes home phone.

                                          I haven't seen a plain modem in years, from either the cable or phone companies. As I mentioned, even business customers get one of these gateway devices, where you disable the gateway if all you want is a modem. Through my work, I have set up several companies on one or the other companies.

                                          BTW, they have replaced the device several times over the years. Most recently, when I got IPTV last year. I went from 2 boxes for Internet & home phone to one and my bandwidth went from 75/10 to 500/20, though as usual with this ISP, it was better than advertised. I have seen over 800 Mb on speedtest. A previous swap, from a Cisco "modem", got me IPv6, more bandwidth and a lower bill.

                                          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
                                          • johnpozJ
                                            johnpoz LAYER 8 Global Moderator @JKnott
                                            last edited by johnpoz

                                            @jknott said in Enabling IPv6 on Comcast home network:

                                            I haven't seen a plain modem in years

                                            There are plenty of them for cable..

                                            Top sellers right now
                                            Motorola MB8600
                                            Motorola MB8611 (2.5gbps interface)
                                            ARRIS SURFboard SB8200
                                            ARRIS Surfboard S33 (2.5gbps interface)
                                            Motorola MB7621
                                            Netgear CM600,CM1000,CM1100,CM1200
                                            etc. etc..

                                            And there sure is way more than just 1 that works with comcast/xfinity..

                                            It is supplied by them and is included in the cost of the service

                                            Cable companies here - pretty much never replace unless it fails, they sure do not replace often enough to justify paying 10$ which is very common.

                                            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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