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    Cant access cable modem config - Virgin Media

    Scheduled Pinned Locked Moved Firewalling
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    • J
      jfish
      last edited by

      I am on Virgin Media in the UK

      My setup as follows

      SH3 Cable modem is in modem only mode –> WAN interface  Pfsense

      The LAN subnet is 192.168.1.0/24 (pfsense is set to 192.168.1.254)

      Everything is working as designed, however I need to login into the cable modem page to check my power levels, and when I enter 192.168.100.1 I get the pfsense login page.

      I have gone into the WAN Interface config page and ensured this option isnt checked

      Block private networks and loopback addresses

      Any help me

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      • JKnottJ
        JKnott
        last edited by

        In my experience, the modem config is not available when the modem is in bridge mode.  However, your ISP should be able to access the modem through the management software.

        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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        • P
          pwood999
          last edited by

          Add a 2nd IP to you WAN port on the 192.168.100.0/24 subnet (dont add a 2nd gateway).  Then pfsense should route from your LAN to the modem admin page.

          Internet access should till use the regular WAN & Def GW.

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          • JKnottJ
            JKnott
            last edited by

            @pwood999:

            Add a 2nd IP to you WAN port on the 192.168.100.0/24 subnet (dont add a 2nd gateway).  Then pfsense should route from your LAN to the modem admin page.

            Internet access should till use the regular WAN & Def GW.

            Again, I have never seen a config screen be available in bridge mode.  Bridge mode means the config screen, router, etc. are not reachable.  Just to verify, I tried connecting my notebook computer directly to my Hitron cable modem, with an IP address of 192.168.0.66.  Hitron modems have a default address of 192.168.0.1.  I am unable to connect to the modem config.  Also, this is not the first time I have tried to do this.  I had the same results with another modem I had here and others.

            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

              @JKnott:

              In my experience, the modem config is not available when the modem is in bridge mode.  However, your ISP should be able to access the modem through the management software.

              If its a modem, then there is no "bridge" mode - if it was a gateway then it could be put into bridge mode - ie just modem mode.

              The standard IP address for many brands of cable modems is 192.168.100.1 - I have never had to do anything special on pfsense to be able to access this.. But yes you can create a vip on your wan connected to the modem and then nat to this vip when wanting to talk to 192.168.100.1

              For example here is my current modem page interface at 192.168.100.1

              modem.png
              modem.png_thumb

              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 2.7.2, 24.11

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              • K
                kpa
                last edited by

                @JKnott:

                In my experience, the modem config is not available when the modem is in bridge mode.  However, your ISP should be able to access the modem through the management software.

                It certainly is but not directly. The bridge interface will have the managment IP address but it will an RFC1918 address which won't be reachable without an IP alias on your WAN interface. This all assuming that we are talking about a straight ethernet bridge on the modem and not some weird PPPoE thingy.

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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by

                  "RFC1918 address which won't be reachable without an IP alias on your WAN interface"

                  No not really… Since as long as the IP was not local pfsense would send it out the wan, the modem would see that IP and answer back.. So as long as your not blocking rfc1918 on your wan you should not have an issue talking without having to create the vip.. This has been my experience with the arris/motorola line of cable modems.

                  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 2.7.2, 24.11

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                  • JKnottJ
                    JKnott
                    last edited by

                    If its a modem, then there is no "bridge" mode - if it was a gateway then it could be put into bridge mode - ie just modem mode.

                    Well, perhaps a bit loose use of terms.  What I have is a box made by Hitron, provided by my cable company.  It is normally configured to be a router/firewall, but can be put into bridge mode, as you'd do when you use a separate router/firewall, as I do.

                    It certainly is but not directly. The bridge interface will have the managment IP address but it will an RFC1918 address which won't be reachable without an IP alias on your WAN interface.

                    I connected my notebook computer, with a static address of 192.168.0.66 /24.  The default for the Hitron box is 192.168.0.1, so it should appear on the same network as my computer.

                    To my knowledge, the only way to restore router mode is to call the support tech, who can then use the management interface, to reconfigure it.  On the user side, when placed in bridge mode, the config interface is no longer reachable.

                    As I mentioned, this is not the only device I've tried this with and they all show the same behavior.

                    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

                      "they all show the same behavior."

                      And those are not cable modems then… When a cable modem boots it will even hand out IP address in the 192.168.100 space...

                      As you stated those are firewall/routers that you put in bridge mode.. So they are gateways that you have disabled the gateway feature and want to use as just a modem..  Or bridge mode - that is completely different than your typical cable modem.. That has no firewall or routing features - its just a Modem!!  Almost all of these answer on 192.168.100.1 as the default.. Atleast the tplink, arris and motorolas 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 24.11 | Lab VMs 2.7.2, 24.11

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                      • K
                        kpa
                        last edited by

                        I can certainly access my modem that is in proper ethernet bridge mode from my LAN computers, no problem there at all. However, I have to use the IP alias on my pfSense WAN because my WAN has a public IP address and any connection from my pfSense going to the management IP address (192.168.1.1) will just hit the ISP gateway on the upper side of the bridge and be just dropped. Remember, any connection to a foreign address that is not in the routing table of your systems gets passed to the upstream default gateway.

                        Edit: Forgot that I also have to use an outbound NAT rule on the WAN that maps the requests going to 192.168.1.1 to the IP alias set on the WAN interface, the modem can't do two-way communication between it and the LAN because it doesn't know the route back to the LAN network.

                        Maybe the modem provided by Virgin Media is just configured that way, off the shelf consumer modems usually offer the management interface even in bridge mode.

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                        • JKnottJ
                          JKnott
                          last edited by

                          As I mentioned earlier, it's perhaps a loose use of terms.  I have it in bridge mode, which means it functions as a modem.  The address is 192.168.0.1, as listed on a sticker attached to it and here:
                          http://setuprouter.com/router/hitron-technologies/ip-address.htm

                          In bridge mode, it does not hand out an RFC 1918 address.  I get a (actually 2 available) public IPv4 address and a /56 IPv6 prefix.

                          When set up as a router/firewall, it will hand out addresses in the 192.168.0.0 /24 range and provide only a single /64 on IPv6.

                          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

                            And that is not a "cable" modem - that is a gateway… Ie modem/router combo device..

                            Which device do you have here? 
                            http://www.hitrontech.com/product-category/cable/

                            Example here hitron cable modem quick start guide
                            https://www.cox.com/content/dam/cox/residential/support/internet/print_media/Hitron_CDA30360_Quick_Reference_Guide.pdf

                            And that states 192.168.100.1, etc..

                            And I do agree there for sure is misuse of terms.. A modem is just that a modem.. You can't put it i bridge mode because there is no other mode ;)  Its a "modem"  Now if its a gateway then then it can provide multiple functions - it is the modem and router in 1 box.  Which those yes you can put in "bridge mode" which turns off its router functions.. And or they can also have some ports that give you your public while others give you a routed/nated rfc1918 address, etc.

                            And then there is just routers - that need a modem in front of them to connect to the internet, etc.

                            Even makers use the wrong terms I have seen where they call their gateway device a modem or router, etc.  When its actually a gateway device that has modem and router functions in 1 box..

                            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 2.7.2, 24.11

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                            • JKnottJ
                              JKnott
                              last edited by

                              @johnpoz:

                              And that is not a "cable" modem - that is a gateway… Ie modem/router combo device..

                              Which device do you have here? 
                              http://www.hitrontech.com/product-category/cable/

                              CGN3ACSMR and it looks like the CGNV4.

                              Example here hitron cable modem quick start guide
                              https://www.cox.com/content/dam/cox/residential/support/internet/print_media/Hitron_CDA30360_Quick_Reference_Guide.pdf

                              And that states 192.168.100.1, etc..

                              The sticker on the unit says 192.168.0.1 and that's the address I used to configure it, before I put it in bridge mode.

                              And I do agree there for sure is misuse of terms.. A modem is just that a modem.. You can't put it i bridge mode because there is no other mode ;)  Its a "modem"  Now if its a gateway then then it can provide multiple functions - it is the modem and router in 1 box.  Which those yes you can put in "bridge mode" which turns off its router functions.. And or they can also have some ports that give you your public while others give you a routed/nated rfc1918 address, etc.

                              I have it in bridge mode, so it functions strictly as a modem.  I haven't seen the router functions in it in about 1.5 years, since I put it in bridge mode.  On this device, there are only 4 connectors on the LAN side.  In gateway mode, they're just 4 switch ports connected to the gateway.  In bridge mode, you can connect 2 devices and get IPv4 & IPv6 addresses for them.  In gateway mode, it's the usual NAT on IPv4 and a single /64 on IPv6.

                              And then there is just routers - that need a modem in front of them to connect to the internet, etc.

                              Even makers use the wrong terms I have seen where they call their gateway device a modem or router, etc.  When its actually a gateway device that has modem and router functions in 1 box..

                              Well, officially, it's a gateway.  But I use it as a modem, with the gateway functions disabled.

                              IMG_20171009_154723.jpg
                              IMG_20171009_154723.jpg_thumb

                              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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