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    Cable modem, pfSense and switches on UPS but still issues with power bumps

    General pfSense Questions
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    • N
      NGUSER6947
      last edited by NGUSER6947

      I have my cable modem, Netgate SG-1100 and switches on UPS. I still have issues with quick power blips that require me to restart the pfSense router.

      I'm pretty sure the UPS it's on isn't dropping out (it's a decent Schneider unit, no alarm indications, and I'm talking really quick blips like easily under 5 minutes).

      What else should I do to alleviate the issues I'm seeing?

      chpalmerC 1 Reply Last reply Reply Quote 0
      • chpalmerC
        chpalmer @NGUSER6947
        last edited by

        @nguser6947

        Unfortunately UPS devices seem to never be able to turn on in time for some products and when they do they come up out of phase.. You could try adding some capacitance to the DC side of the power supply but in my case I simply run my stuff off a battery bank that is charged by a Samlex battery charger.

        Are you positive that your UPS is true sine wave? You might ask the manufacturer.

        Triggering snowflakes one by one..
        Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

        N 1 Reply Last reply Reply Quote 0
        • N
          NGUSER6947 @chpalmer
          last edited by

          @chpalmer I do not know and don't really know what that means TBH. But I can try to find out.

          1 Reply Last reply Reply Quote 0
          • F
            FSC830
            last edited by FSC830

            Me too using a Schneider (APC) UPS.
            A self-test is scheduled in an interval of 14 days.
            The test itself lasts only a few seconds and pfSense always reports "on battery"/"AC returned" but was never shutting down (SG-3100).
            In service a shutdown is configured at a certain battery level.

            Did you check your settings. Is the appliance really off after the power blip?
            How does it behave exactly?

            From an AC outlet the form of the AC is usually a sine wave.
            Some (or most) UPS devices can not provide an exact sinus wave, it sometimes looks more than a "stairway triangle" and some connected devices dont like that.
            Best way to check this is using an oscilloscope.

            But be aware: dealing with voltage at AC outlet there is a potential danger of life!!!

            Regards

            N 1 Reply Last reply Reply Quote 0
            • M
              mer
              last edited by

              most upses can be configured on "how quickly they transfer", usually called "sensitivity". If you set sensitivity to "High", you may wind up switching to UPS too often, set it to Low and you may not switch often enough. If it's set Low and wall power goes out of range beyond what the device can handle, you can have problems.

              Some UPS (maybe most higher quality/price ones?) effectively run off the battery all the time, generating good power always. The wall power is then used to simply keep the batteries charged.
              Others funnel wall power through and then switch to running off the batteries when power is lost. If it takes too long to switch your devices see it.

              Now on a lot of UPSes there are some outlets that are labelled "Surge protection only" which are not on the battery. I think on APC UPSes outlets are labelled either "Battery Backed" or "Surge Only".

              Double check that your devices are plugged into outlets that are backed by the battery.

              F 1 Reply Last reply Reply Quote 0
              • F
                FSC830 @mer
                last edited by

                @mer said in Cable modem, pfSense and switches on UPS but still issues with power bumps:

                Some UPS (maybe most higher quality/price ones?) effectively run off the battery all the time, generating good power always. The wall power is then used to simply keep the batteries charged.

                Thats different types of UPS devices.
                The ones runnings always are called online UPS, the other ones are standby UPS.
                Usually a standby UPS causes an interruption when AC is off, but in a ranga of milliseconds, so most devices do not have any issue with that.

                Regards

                1 Reply Last reply Reply Quote 1
                • N
                  NGUSER6947 @FSC830
                  last edited by NGUSER6947

                  @fsc830 Everything critical is plugged into the UPS outlets on the back of the UPS. Only ancillary items such as camera POE bricks are in the Surge protection only outlets.

                  Symptoms - the SG-1100 doesn't restart, it just acts funny. Like yesterday, I was fighting what I thought were PC issues with connectivity (just 2 PCs. My Roku and other devices were working fine). Finally just rebooted the SG-1100 and the problems went away.

                  M 1 Reply Last reply Reply Quote 0
                  • M
                    mer @NGUSER6947
                    last edited by

                    @nguser6947 Hmm. How old are the batteries on the UPS? Perhaps they need replacing. Maybe the overall load on the UPS?
                    Other than that, all I can think of is sensitivity setting or the UPS needs to be replaced.

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

                      So what state does it end up in after one of these outages?

                      What does it report for uptime?

                      It's more likely, IMO, that some upstream device goes out and your cable modem starts handing out private IPs.

                      N 1 Reply Last reply Reply Quote 1
                      • N
                        NGUSER6947 @stephenw10
                        last edited by

                        @stephenw10 I'll need to check the uptime value next time this happens. The only device upstream is the cable modem, also on a (different) UPS.

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

                          If the outage causes the modem to lose sync it might bounce the WAN link to pfSense and start handing out private IPs. You may need to set the pfSense WAN to reject leases from that.
                          https://docs.netgate.com/pfsense/en/latest/interfaces/configure-ipv4.html#dhcp

                          Steve

                          1 Reply Last reply Reply Quote 0
                          • chpalmerC
                            chpalmer @NGUSER6947
                            last edited by

                            @nguser6947 said in Cable modem, pfSense and switches on UPS but still issues with power bumps:

                            @stephenw10 I'll need to check the uptime value next time this happens. The only device upstream is the cable modem, also on a (different) UPS.

                            Some day when you get the chance.. initiate a power outage by flipping your breakers while someone watches each device. See if one blips.

                            I would not have the modem and router on separate UPS units.. but that is just me.

                            What model is your cable modem? (does it have a backup battery?)

                            Triggering snowflakes one by one..
                            Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

                            N 1 Reply Last reply Reply Quote 0
                            • N
                              NGUSER6947 @chpalmer
                              last edited by

                              @chpalmer Cable modem is an Arris 32 channel. About 2 years old. Only in a different UPS due to its location in the house.

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

                                The modem might lose sync even if it doesn't lose power.

                                chpalmerC 1 Reply Last reply Reply Quote 0
                                • chpalmerC
                                  chpalmer @stephenw10
                                  last edited by

                                  @stephenw10 said in Cable modem, pfSense and switches on UPS but still issues with power bumps:

                                  The modem might lose sync even if it doesn't lose power.

                                  Very true.

                                  Since he said Arris 32 channel which would be a DOCSIS 3 model..
                                  https://approvedmodems.org/bad-modems/

                                  Triggering snowflakes one by one..
                                  Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

                                  1 Reply Last reply Reply Quote 1
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