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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 @chpalmer
    last edited by Apr 6, 2023, 10:08 PM

    @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 Apr 7, 2023, 8:08 AM Apr 7, 2023, 8:08 AM

      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 Apr 7, 2023, 12:42 PM Reply Quote 0
      • M
        mer
        last edited by Apr 7, 2023, 9:43 AM

        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 Apr 7, 2023, 10:45 AM Reply Quote 0
        • F
          FSC830 @mer
          last edited by Apr 7, 2023, 10:45 AM

          @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 Apr 7, 2023, 12:42 PM Apr 7, 2023, 12:42 PM

            @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 Apr 7, 2023, 3:12 PM Reply Quote 0
            • M
              mer @NGUSER6947
              last edited by Apr 7, 2023, 3:12 PM

              @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
              • S
                stephenw10 Netgate Administrator
                last edited by Apr 7, 2023, 4:37 PM

                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 Apr 7, 2023, 4:57 PM Reply Quote 1
                • N
                  NGUSER6947 @stephenw10
                  last edited by Apr 7, 2023, 4:57 PM

                  @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.

                  C 1 Reply Last reply Apr 7, 2023, 5:22 PM Reply Quote 0
                  • S
                    stephenw10 Netgate Administrator
                    last edited by Apr 7, 2023, 5:13 PM

                    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

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                    • C
                      chpalmer @NGUSER6947
                      last edited by Apr 7, 2023, 5:22 PM

                      @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 Apr 7, 2023, 10:06 PM Reply Quote 0
                      • N
                        NGUSER6947 @chpalmer
                        last edited by Apr 7, 2023, 10:06 PM

                        @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
                        • S
                          stephenw10 Netgate Administrator
                          last edited by Apr 8, 2023, 1:25 PM

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

                          C 1 Reply Last reply Apr 8, 2023, 2:06 PM Reply Quote 0
                          • C
                            chpalmer @stephenw10
                            last edited by Apr 8, 2023, 2:06 PM

                            @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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