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    Trying to access my Comcast modem via the LAN

    Scheduled Pinned Locked Moved General pfSense Questions
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    • 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.

          1 Reply Last reply Reply Quote 1
          • 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.

            1 Reply Last reply Reply Quote 0
            • 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?

                  1 Reply Last reply Reply Quote 0
                  • 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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                        • B
                          bazzacad
                          last edited by

                          I added the VIP & NAP, but no luck. :-(
                          I can ping the VIP & modem from the LAN.
                          0d11ce55-5e3a-4d78-b016-1ff697db5809-image.png
                          2885c82c-575c-42a7-aefa-ca1029f78803-image.png
                          279cd2a6-a488-4324-baa8-f9f61b041492-image.png

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                          • johnpozJ
                            johnpoz LAYER 8 Global Moderator
                            last edited by johnpoz

                            Well you got something back.. Or you wouldn't have gotten that page.. So you got a syn,ack I would assume.. So your vip is working.

                            Sniff on the wan when you try and open the page.. do you see the syn,ack come back from your syn.. If so pfsense is doing what you told it to do.

                            Why did you do a /32? Set that to /24

                            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

                              OK I fixed the /32 thx.
                              By Sniff do you mean WireShark?
                              Or can I do it in pfSense?

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                              • stephenw10S
                                stephenw10 Netgate Administrator
                                last edited by

                                You can do it within pfSense:
                                https://docs.netgate.com/pfsense/en/latest/monitoring/performing-a-packet-capture.html

                                Steve

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