PowerFallback

UPS Software, Monitoring and Automatic Shutdown

A UPS only buys you minutes. Software is what turns those minutes into a clean shutdown instead of a hard power cut, and these guides show how to configure it on each platform.

Without a data connection, a UPS has no way to tell your computer that the battery is running out. It keeps the load running until the battery is flat, and then the power drops exactly as if there had been no UPS at all, only later. For a desktop that may just mean lost work. For a NAS rebuilding an array, a hypervisor full of virtual machines or a database server, an abrupt cut is the very thing you bought the UPS to avoid.

UPS software closes that gap. Over USB, serial or the network, it reads the UPS status (on line, on battery, battery charge, estimated runtime, load) and acts on rules you set: notify someone, wait a while, then shut machines down in the right order while there is still energy left.

How this section is organized

The one rule that matters most

Configure shutdown to start while a comfortable amount of runtime remains, then test it by pulling the UPS plug from the wall. A shutdown that has never been tested is a guess. Battery runtime estimates shrink as batteries age, so a threshold that left five spare minutes when the battery was new may leave none three years later. Our guide to how much runtime you need explains how to budget the time, and self-tests and runtime calibration explains how to keep the estimate honest.

If your computer does not see the UPS at all, start with UPS not detected by computer before changing any software settings.

All Software & Monitoring guides

Software & MonitoringUPS Software: What It Does and Which Tool to UseWhat UPS software actually does, how it talks to the UPS, and how to pick between built-in, vendor and open source tools.Software & MonitoringPowerChute and PowerPanel: Vendor UPS Software ExplainedWhich PowerChute or PowerPanel edition fits your UPS, what it adds over built-in OS support, and the mistakes that break shutdowns.Software & MonitoringNetwork UPS Tools (NUT): A Complete Setup GuideWorking NUT configuration for one host or many, with the shutdown sequence explained and fixes for the usual errors.Software & Monitoringapcupsd: Configuring APC UPS Monitoring and ShutdownA practical apcupsd setup for APC units, from the config file to network clients, event scripts and when NUT is the better choice.Software & MonitoringAutomatic UPS Shutdown on Windows Without Extra SoftwareUse Windows' built-in battery settings to shut down or hibernate a PC cleanly when the UPS runs low.Software & MonitoringSetting Up a UPS on a Mac: Shutdown Options and pmsetWhere macOS hides its UPS shutdown options, how pmset exposes them, and how to test a clean shutdown.Software & MonitoringSynology NAS UPS Setup: USB, Network UPS Server and NUT ClientsConnect a UPS to a Synology NAS, share it with other devices, and make DSM a client of any NUT server.Software & MonitoringTrueNAS UPS Setup: The UPS Service, Shutdown Modes and Remote ClientsConfigure the NUT-based UPS service on TrueNAS, choose a shutdown mode, and share the UPS with other machines.Software & MonitoringUnraid UPS Setup: Built-in apcupsd, the NUT Plugin and Shutdown TimingSet up Unraid's UPS settings, decide when to use the NUT plugin, and budget time for a clean array stop.Software & MonitoringProxmox VE UPS Shutdown: NUT on the Host and Getting the Order RightRun NUT on the Proxmox host, get guests to stop cleanly, and sequence hypervisors before shared storage.Software & MonitoringMonitoring a UPS in Home Assistant: NUT Integration, Add-on and AutomationsBring UPS status into Home Assistant with NUT, then alert and automate on power loss and low battery.Software & MonitoringUPS Network Management Cards and SNMP MonitoringHow network management cards and SNMP put a UPS on the network, with OIDs, NUT config and security basics.