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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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    • B
      BlankSpace
      last edited by

      I forced the speed at 1000 and duplex at full, bounced the WAN interface and it came back up and grabbed the IP with no issues. This may be the solution...

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

        Nice. You still get the expected throughput?

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

          Well, I am not sure. I thought it looked like my RTT and RTTsd increased a little and then I did some speedtests from the pfs command line and they were all over the place. So it is possible my throughput suffered, or just busy cable at this time of the night. I will need to try some speedtests at different times to confirm.

          However, since it seemed to solve the problem by adjusting the negotiation, what other workarounds would there be if indeed my throughput suffered from forcing negotiation?

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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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            • B
              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.

              1 Reply Last reply Reply Quote 0
              • 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.

                  1 Reply Last reply Reply Quote 0
                  • 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

                    B 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:

                      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)

                      B 1 Reply Last reply Reply Quote 0
                      • B
                        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)

                          1 Reply Last reply Reply Quote 0
                          • 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?

                            1 Reply Last reply Reply Quote 0
                            • 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

                              B 1 Reply Last reply Reply Quote 0
                              • 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)

                                  B 1 Reply Last reply Reply Quote 0
                                  • 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.

                                      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:

                                        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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