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    Trying to access my Comcast modem via the LAN

    Scheduled Pinned Locked Moved General pfSense Questions
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    • chpalmerC
      chpalmer @bazzacad
      last edited by

      @bazzacad said in Trying to access my Comcast modem via the LAN:

      so that makes me think it wasn't a firmware update on the modem.

      I don't have any static Comcast sites left to test..

      You are plugged into the first port on the modem?

      Triggering snowflakes one by one..
      Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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      • JKnottJ
        JKnott @bazzacad
        last edited by

        @bazzacad said in Trying to access my Comcast modem via the LAN:

        We don't use IPv6.

        Check again. According to the pictures you provided, you have a prefix assigned to you. It's 2603:3024:1003:4500:: /56. That means if you were using pfSense as intended, you'd have 256 /64 IPv6 networks, each of which could have up to 2^64 addresses. However, it also appears they're putting the /56 directly on the LAN, which won't work. The LAN should have only a /64 and nothing else. Is there anywhere in that modem to select a single /64? With the Hitron modem I have, in router mode, it provides only a single /64, but in bridge mode I get the full /56.

        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 @chpalmer
          last edited by

          @chpalmer said in Trying to access my Comcast modem via the LAN:

          Yep.. I get it.. But read the article from handymanhowto I linked above.

          NAT has gone from being a hack to get around the IPv4 address shortage to a curse on networking. If you have a block of public addresses, why the @$^$^#%$&$ should you be forced to use NAT? NAT breaks things and with that setup, they're forcing you to use 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...

          chpalmerC 1 Reply Last reply Reply Quote 0
          • chpalmerC
            chpalmer @JKnott
            last edited by

            @JKnott said in Trying to access my Comcast modem via the LAN:

            @chpalmer said in Trying to access my Comcast modem via the LAN:

            Yep.. I get it.. But read the article from handymanhowto I linked above.

            NAT has gone from being a hack to get around the IPv4 address shortage to a curse on networking. If you have a block of public addresses, why the @$^$^#%$&$ should you be forced to use NAT? NAT breaks things and with that setup, they're forcing you to use it.

            your preaching to the choir! Ive bitched about their requirement for years.

            Triggering snowflakes one by one..
            Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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

              @chpalmer said in Trying to access my Comcast modem via the LAN:

              your preaching to the choir! Ive bitched about their requirement for years.

              Can you or Comcast put that modem in bridge mode? That's the way it should be done. You'd then configure pfSense to use the 50. address you mentioned earlier. You would then have a /29 prefix on IPv4 and /56 on IPv6. PfSense can then pick off 1 or more /64s from that /56.

              BTW, the WAN IP and gateway addresses look a little strange. They should within the same prefix.

              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...

              chpalmerC JKnottJ 2 Replies Last reply Reply Quote 0
              • chpalmerC
                chpalmer @JKnott
                last edited by

                @JKnott said in Trying to access my Comcast modem via the LAN:

                Can you or Comcast put that modem in bridge mode?

                Comcast will not put the modem in bridgemode if you have static IP addresses.

                Triggering snowflakes one by one..
                Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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

                  @JKnott said in Trying to access my Comcast modem via the LAN:

                  Can you or Comcast put that modem in bridge mode?

                  After a couple of seconds of hard Googling, I found this. This is the sort of thing I did with my modem. I put it in bridge mode and let pfSense handle everything else.

                  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...

                  chpalmerC 1 Reply Last reply Reply Quote 0
                  • chpalmerC
                    chpalmer @JKnott
                    last edited by

                    @JKnott said in Trying to access my Comcast modem via the LAN:

                    After a couple of seconds of hard Googling, I found this.

                    From that page-

                    "Cannot have a fixed Static IP assignment"

                    Triggering snowflakes one by one..
                    Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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                    • JKnottJ
                      JKnott @chpalmer
                      last edited by

                      @chpalmer said in Trying to access my Comcast modem via the LAN:

                      Comcast will not put the modem in bridgemode if you have static IP addresses.

                      Does the line "Cannot have a fixed Static IP assignment" in the docs refer to the modem or your LAN? With my modem, there is no address I can reach from outside my network, but I can access it on the LAN side with an address in the 192.168 range. If you have a block of addresses, they should be able to route to use regardless of whether they use NAT or 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...

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                      • chpalmerC
                        chpalmer
                        last edited by

                        The modem doubles as the local router for Comcast's purposes. With the static addresses I use with Wave Broadband the statics are forwarded to you. I have my pure bridge Motorola MB8600 in place before my repurposed XTM5 box here with a VIP for my statics. This is how I prefer it to be.

                        Comcast uses their modem as a router on site. The IP's are routed to you via this method.

                        So on the same interface you get NAT'd traffic and the routed IP traffic.

                        Triggering snowflakes one by one..
                        Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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

                          @chpalmer said in Trying to access my Comcast modem via the LAN:

                          The modem doubles as the local router for Comcast's purposes.

                          Other companies do similar, but have addresses entirely separate from the customer's internet access. In those, putting the modem in bridge mode affects only the internet connection. by "Comcast's purposes", do you mean public "Xfinity" WiFi? If so, that's definitely a different address and has nothing to do with the modem mode. You'd be putting only your Internet access portion of the router into bridge mode, not the entire box. Think of if as 2 services sharing the same box.

                          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...

                          chpalmerC 1 Reply Last reply Reply Quote 0
                          • A
                            alpineaudio
                            last edited by alpineaudio

                            Is there a reason you want to stick with Comcast's modem router combo? Why not just get a Docsis 3.1 modem (https://www.arris.com/surfboard/products/cable-modems/sb8200/ gig ready). That's what I did and then went with my own router, that way I eliminated all their crap or issues.

                            chpalmerC 1 Reply Last reply Reply Quote 0
                            • chpalmerC
                              chpalmer @alpineaudio
                              last edited by

                              @alpineaudio said in Trying to access my Comcast modem via the LAN:

                              Is there a reason you want to stick with Comcast's modem router combo?

                              Yep he does. You need to read the entire thread to find it but he is using static addresses and Comcast requires the use of their equipment.

                              I'm really surprised there are not more Comcast savoy people reading this and chiming in. Its pretty well known information.

                              Triggering snowflakes one by one..
                              Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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                              • chpalmerC
                                chpalmer @JKnott
                                last edited by

                                @JKnott said in Trying to access my Comcast modem via the LAN:

                                @chpalmer said in Trying to access my Comcast modem via the LAN:

                                The modem doubles as the local router for Comcast's purposes.

                                Other companies do similar, by "Comcast's purposes", do you mean public "Xfinity" WiFi?

                                No not the public WIFI crap. Speaking of crap we usually call them Comcrap due to "crap" like this.

                                By their purposes I mean in order to provide the static IP's they use a local router. (probably not the best use of "their purposes" but I digress.. The Modem/Router combination truly does the routing on site. If the OP was to show his "quality" logs you would see the ping is very small to the gateway router because that is indeed in the modem in this situation.

                                Triggering snowflakes one by one..
                                Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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                                • johnpozJ
                                  johnpoz LAYER 8 Global Moderator
                                  last edited by

                                  Back on subject just create a vip

                                  On your wan create a vip, lets call it 10.1.10.2, then create an outbound nat to that vip... There you go access.

                                  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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                                  • B
                                    bazzacad
                                    last edited by

                                    Thanks for all the help everyone. Sorry this became a longer topic then I expected. I'll try the VIP option this evening...

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                                    • B
                                      bazzacad
                                      last edited by

                                      So I want the VIP to be the destination for the outbound NAT?

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                                      • johnpozJ
                                        johnpoz LAYER 8 Global Moderator
                                        last edited by johnpoz

                                        No the vip would be the interface for the nat, dest would be the IP your trying to get to or just the network.. One sec show you a pic.. I don't need it to access my modem.. But I can set one up real quick to show you. My modem which is bridged can still be access via is 192.168.100.1 address..

                                        So create vip on wan say 192.168.100.2 - one sec brb.

                                        here you go. Notice how I selected the vip as the translation in the outbound. You only need to use hybrid not manual.. So now anything coming from 192.168.9.0/24 network going to a 192.168.100.0/24 network will go out the wan using that IP..

                                        vip.png

                                        And there you go access
                                        modemaccess.png

                                        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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                                        • B
                                          bazzacad
                                          last edited by

                                          Thanks for the screen shots. They're very helpful.
                                          So I'm thinking this is what I'll try. Does it look correct...?
                                          Also, my NAT mode is already set to Manual. Needed it for some PBX rules.

                                          3e04464b-cf59-4cb5-85c4-e247f7469db2-image.png

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                                          • johnpozJ
                                            johnpoz LAYER 8 Global Moderator
                                            last edited by

                                            Yeah that looks right.

                                            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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