Network UPS Tools (NUT) is a client/server monitoring system that\\ allows computers to share uninterruptible power supply (UPS) and\\ power distribution unit (PDU) hardware. Clients access the hardware\\ through the server, and are notified whenever the power status\\ changes. \\ upsd is responsible for serving the data from the drivers to the\\ clients. It connects to each driver and maintains a local cache of the\\ current state. Queries from the clients are served from this cache, so\\ delays are minimal. This program is essential, and must be running at\\ all times to actually make any use out of the drivers and clients.\\ \\