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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

      If you set a fixed speed at one end you would usually have to set it fixed at both ends. Otherwise the other side might default to 100Mb half or something.
      Putting a switch in between would also remove negotiation issues between those two specific devices as both then negotiate with the switch instead.

      Steve

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        BlankSpace @stephenw10
        last edited by

        @stephenw10

        Ah, yes I forgot about that option. Any reason it only happens if the interface is disabled or loses the link with the cable modem when the modem reboots? When I restart pfs there are no issues.

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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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                          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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