@michaelharley no experience of this specific case, but I'm pretty happy with a rack mountable #PowerWalker unit. It doesn't have network interfaces, however, I connected it directly to my server running Home Assistant via USB. It is supported by NUT (https://networkupstools.org), it's the standard for UPS management under Linux, and has an homeassistant integration: https://www.home-assistant.io/integrations/nut/