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    WAN fails to keep DHCP address on cable modem reboot

    Scheduled Pinned Locked Moved General pfSense Questions
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    • stephenw10S
      stephenw10 Netgate Administrator
      last edited by

      Hmm, well that might imply it negotiates differently when the modem comes up.

      If your modem really is just a modem and doesn't have a switch IC then I would expect to see a speed/duplex mismatch if you set pfSense to fixed. That usually kills throughput as you get loads or errors on the interface.

      Adding a switch in between would be a better test in that situation.

      Steve

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      • B
        BlankSpace @stephenw10
        last edited by BlankSpace

        @stephenw10

        I had two modems that did this, the first was the cable company provided Arris CM8200. The Arris modems would actually go into a boot loop everytime pfs dropped the IP and tried to renegotiate. They would actually lose signal on the cable end and just keep looping until pfs was restarted.

        Then I purchased my own Netgear Nighthawk CM1200. The Netgear has 4 ports but it is not a switch per se, it is for link aggregation and multiple IP address.

        I just tested speed this morning when manually forcing 1000/full and it did indeed go down, by alot, each time I did the speedtest.

        I do have some spare switches laying around that I will try. It's not really too big of an issue because I can always restart pfs and in 60 seconds its back up anyway. But sometimes I want to quickly bounce the cable modem to clear the logs and not have to restart pfs.

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        • stephenw10S
          stephenw10 Netgate Administrator
          last edited by

          It would confirm it's a link problem of some type though. Adding a switch is a good test a least.

          Steve

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          • DaddyGoD
            DaddyGo @BlankSpace
            last edited by

            @BlankSpace said in WAN fails to keep DHCP address on cable modem reboot:

            This may be the solution...

            Due to the plenty of "noname" chip (PHY, eth. magnetics, PCB. etc.) manufacturers, unfortunately we encounter more and more of this problem.(Free after... @chpalmer https://www.badmodems.com/)

            (the bad principle lately is that the modem should be cheap and not really the function is the point)

            It's good if your test was successful. 😉

            you may still be able to refine your settings with these parameters (Protocol timing)

            91db0bc8-1720-4dc5-b8d5-584caa080157-image.png

            Cats bury it so they can't see it!
            (You know what I mean if you have a cat)

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              BlankSpace @DaddyGo
              last edited by

              @DaddyGo

              Thanks, I will need to read up on those settings, I have never messed with them before and do not know what each does.

              DaddyGoD 1 Reply Last reply Reply Quote 0
              • DaddyGoD
                DaddyGo @BlankSpace
                last edited by

                @BlankSpace said in WAN fails to keep DHCP address on cable modem reboot:

                Thanks, I will need to read up on those settings,

                Okéééé:
                https://docs.netgate.com/pfsense/en/latest/book/interfaces/ipv4-wan-types.html

                Cats bury it so they can't see it!
                (You know what I mean if you have a cat)

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                • B
                  BlankSpace @stephenw10
                  last edited by BlankSpace

                  @stephenw10

                  So I put a new cheap unmanaged gigabit switch (Netgear GS205) in between pfs and the modem. And it does the same thing, pfs can't get a stable link, keeps dropping and connecting in a loop. If I restart pfs, no issues.

                  During this time, this is being displayed on the console: "config_aqm Unable to configure flowset, flowset busy!"

                  Can it be related to the limiters I have created?

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                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by

                    Yes. It could be.
                    Though that could also just be a symptom of the limiter queues filling when the link goes down.

                    Try removing them.

                    You might also disabling flow control on igb3 if it is enabled.

                    Steve

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                    • B
                      BlankSpace @stephenw10
                      last edited by

                      @stephenw10

                      I'm basically running upload and download limiters using FQ_CODEL for bufferbloat. I just followed the documentation in a video I found.

                      igb3 is my WAN interface.

                      DaddyGoD 1 Reply Last reply Reply Quote 0
                      • DaddyGoD
                        DaddyGo @BlankSpace
                        last edited by

                        @BlankSpace

                        @stephenw10 "You might also disabling flow control on igb3 if it is enabled."

                        in addition I would even disable EEE (in loader.conf.local)

                        0275a0ef-ebfc-4010-a856-cc66b6459890-image.png

                        Cats bury it so they can't see it!
                        (You know what I mean if you have a cat)

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                        • B
                          BlankSpace @DaddyGo
                          last edited by

                          @DaddyGo

                          Thanks, I created loader.conf.local in /boot and added those lines. Safe to assume if I only have igb0 through igb3, that's all I need?

                          DaddyGoD 1 Reply Last reply Reply Quote 0
                          • stephenw10S
                            stephenw10 Netgate Administrator
                            last edited by stephenw10

                            Yes. It won't hurt adding more but it won't do anything except maybe log an error since you only have 4 NICs, those further OIDs don't exist.

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                            • DaddyGoD
                              DaddyGo @BlankSpace
                              last edited by

                              @BlankSpace said in WAN fails to keep DHCP address on cable modem reboot:

                              only have igb0 through igb3, that's all I need?

                              As @stephenw10 says too

                              "prtsc" shows in my example one I350-T4 and one I350-F4 are configured so it shows 0 to 7.

                              Cats bury it so they can't see it!
                              (You know what I mean if you have a cat)

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