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    Xfinity - Comcast - Static IP Issue

    Scheduled Pinned Locked Moved General pfSense Questions
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    • DenverDesktopsSupportD
      DenverDesktopsSupport
      last edited by

      Comcast WAN issue.

      Set up a new network at my office with Netgate configured to WAN DHCP. All working well with VLANS, LAN DHCP, wifi AP's etc. Take gear to client site and set up static IP with Comcast. No matter the WAN connection is not picked up and can't get internet functioning. Tried passive mode and bridged mode with Comcast, but still no success. We have a single IP with Comcast and someone mentioned sometimes CC has issues with loading single IP's into the gateway modem and I should buy a block of 5. Anyone else see this? Am I missing something on the WAN interface? Pretty straight forward - Static IP/GW/30.

      Thank you.
      DenverDTS

      S 1 Reply Last reply Reply Quote 0
      • S
        SteveITS Galactic Empire @DenverDesktopsSupport
        last edited by

        @denverdesktopssupport Especially if it's replacing a router, try powering off the Comcast router. Those don't seem to do well if an IP moves to a new device. Or change the MAC address on the pfSense to the one on the old router.

        It is also possible they messed up and gave you the wrong IP or someone else's IP, I've seen that before.

        Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
        When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
        Upvote ๐Ÿ‘ helpful posts!

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        • DenverDesktopsSupportD
          DenverDesktopsSupport
          last edited by

          Steve -

          The old router is the Comcast router that is staying in place, only changing to passive or bridged mode.

          Did try power down the router multiple times with no success and Comcast loaded IP a few times. Can I spoof the current MAC address of the Comcast router to the WAN interface without any issues?

          Thanks for the ideas.

          DenverDTS

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          • S
            SteveITS Galactic Empire @DenverDesktopsSupport
            last edited by

            @denverdesktopssupport So you're replacing the Comcast router? What connects to their physical cable?

            If you're behind their router it should work in bridge mode unless something is wrong on their end.

            If you configure pfSense WAN for DHCP does it pick up a 10.1.10.x WAN address and connect out? Just to see if it functions.

            I was referring to replacing an existing router that is already behind a Comcast router.

            Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
            When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
            Upvote ๐Ÿ‘ helpful posts!

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            • DenverDesktopsSupportD
              DenverDesktopsSupport
              last edited by

              The Comcast router is not being replaced. That is currently what is handing out 10.1.10.x. Yes, if the PFsense WAN interface is set to WAN DHCP and the router is in "standard mode" it grabs a 10.1.10.x. It does not work when in bridged more or what Comcast calls passive mode.

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                akuma1x @DenverDesktopsSupport
                last edited by

                @denverdesktopssupport Your pfsense box probably isn't working when the Comcast modem is in bridged or passive because, when you switch it to this mode, you need specific info from the ISP.

                Mine is in this mode and I needed to contact them to get the following:

                WAN IP address (to use in pfsense)
                Gateway IP Address
                Subnet Mask
                DNS servers (should not be required, but maybe)

                Do you have any of that info from Comcast? If you do, then you can setup your pfsense WAN interface to use this info and it should get you online. If you do not, you can still use DHCP from Comcast on your WAN interface, you just need to use some other private IP address space on your internal LAN network - 192.168.X.X or 172.16.X.X for example. I have always found it best to NOT use the 10.X space when the ISP also uses a DHCP server in the same space. It's easier to troubleshoot problems when the address space doesn't look similar.

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                • DenverDesktopsSupportD
                  DenverDesktopsSupport
                  last edited by

                  I have the static from Comcast and it has been entered into the WAN interface on the Netgate. That is the issue as it is not working.

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                    akuma1x @DenverDesktopsSupport
                    last edited by

                    @denverdesktopssupport And how about the gateway info? Did you put that into pfsense?

                    What happens if you plug a PC (laptop) directly into the Comcast modem? Do you get an IP address and DNS from the modem? Can the laptop browse the internet?

                    You're missing something here, this works either using DHCP from the Comcast modem, or using the static settings (all of them) setup into pfsense.

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                    • jimpJ jimp moved this topic from Problems Installing or Upgrading pfSense Software on
                    • DenverDesktopsSupportD
                      DenverDesktopsSupport
                      last edited by

                      Configuring my LAN interface with the public static IP provided by Comcast, gets me online. It does not want to pass through to the PFsense WAN interface.

                      ? stephenw10S 2 Replies Last reply Reply Quote 0
                      • ?
                        A Former User @DenverDesktopsSupport
                        last edited by

                        @denverdesktopssupport Could you test? and publish logs (so we can help you better)

                        I would like it to be more specific, explain how each thing is physically connected, ok?

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                        • stephenw10S
                          stephenw10 Netgate Administrator @DenverDesktopsSupport
                          last edited by

                          @denverdesktopssupport said in Xfinity - Comcast - Static IP Issue:

                          Configuring my LAN interface with the public static IP provided by Comcast, gets me online.

                          The Comcast router LAN?

                          Can you connect a laptop directly to9 the CC router when it's in 'bridge mode' and use the static IP?

                          This seems like the Comcast device is not correctly configured for your static IP. That doesn't seem that uncommon, there are a number of threads like this. Is this the first time that connection is using a static IP?

                          Steve

                          DenverDesktopsSupportD 1 Reply Last reply Reply Quote 0
                          • DenverDesktopsSupportD
                            DenverDesktopsSupport
                            last edited by

                            Bridged mode doesn't work at all. Passive move is supposedly the correct method of configuration, but that isn't playing nice either. However, yes I can assign the LAN of my laptop the WAN IP address and can connect to the internet.

                            I agree, I think something is going on with the Comcast device. The WAN interface connection on the PFsense is pretty straight forward. One thread stated to just turn off DHCP and the firewall off on the Comcast router and that did the trick.

                            Going back out tomorrow morning, weather permitting and can hopefully provide more detail if need be.

                            Thanks
                            DenverDTS

                            stephenw10S 1 Reply Last reply Reply Quote 0
                            • DenverDesktopsSupportD
                              DenverDesktopsSupport @stephenw10
                              last edited by

                              @stephenw10 and yes, first time using a static IP at this site.

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                              • stephenw10S
                                stephenw10 Netgate Administrator @DenverDesktopsSupport
                                last edited by

                                @denverdesktopssupport said in Xfinity - Comcast - Static IP Issue:

                                However, yes I can assign the LAN of my laptop the WAN IP address and can connect to the internet.

                                Hmm, there really shouldn't be any difference between that and pfSense using it. Other than the MAC address which should be fine with a reboot in between.

                                Steve

                                DenverDesktopsSupportD 1 Reply Last reply Reply Quote 0
                                • DenverDesktopsSupportD
                                  DenverDesktopsSupport @stephenw10
                                  last edited by

                                  @stephenw10 agreed.

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                                  • stephenw10S
                                    stephenw10 Netgate Administrator
                                    last edited by

                                    Well I'd checking the ARP table for any devices on the WAN. Running a pcap on WAN to see if anything appears there.

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                                    • DenverDesktopsSupportD
                                      DenverDesktopsSupport
                                      last edited by

                                      Well not sure exactly what the issue was, but after doing a restore of the PFsense backup, the device is working as expected. WAN port is up, client is happy and earth is back on axis. :)

                                      FYI - no need to put the Comcast router in passive mode. Just turn off DHCP/Firewall and Wifi.

                                      Thanks for the assistance!!

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                                        smartinesmir
                                        last edited by smartinesmir

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