This version of the page reflects NUT release v2.8.2 with codebase commited 440ca2348 at 2024-04-01T22:07:23+02:00
Options, features and capabilities in current development (and future releases) are detailed on the main site and may differ from ones described here.
NUT provides many features, and is always improving. Thus this list may lag behind the current code.
Features frequently appear during the development cycles, so be sure to look at the release notes and change logs to see the latest additions.
Various communication types and many protocols are supported with the same common interface:
Be sure to plug your network’s physical hardware (switches, hubs, routers, bridges, …) into the UPS!
upsdrvctl start
.
These are the most common situations for monitoring UPS hardware. Other ways are possible, but they are mostly variations of these four.
these examples show serial communications for simplicity, but USB or SNMP or any other monitoring is also possible.
One UPS, one computer. This is also known as "Standalone" configuration.
This is the configuration that most users will use. You need at least a
driver, upsd
, and upsmon
running.
One UPS, multiple computers. Only one of them can actually talk to the UPS directly. That’s where the network comes in:
upsd
, and upsmon
in
"primary" mode.
upsmon
in "secondary" mode which all
connect to upsd
on Primary.
This is useful when you have a very large UPS that’s capable of running multiple systems simultaneously. There is no longer the need to buy a bunch of individual UPSes or "sharing" hardware, since this software will handle the sharing for you.
Some systems have multiple power supplies and cords. You typically find
this on high-end servers that allow hot-swap and other fun features.
In this case, you run multiple drivers (one per UPS), a single upsd
,
and a single upsmon
(as a primary for both UPS 1 and UPS 2)
This software understands that some of these servers can also run with some of the supplies gone. For this reason, every UPS is assigned a "power value" — the quantity of power supplies that it feeds on this system.
The total available "power value" is compared to the minimum that is required for that hardware. For example, if you have 3 power supplies and 3 UPSes, but only 2 supplies must be running at any given moment, the minimum would be 2.
This means that you can safely lose any one UPS and the software will handle it properly by remaining online and not causing a shut down.
You can even have a UPS that has the serial port connected to a system that it’s not feeding. Sometimes a PC will be close to a UPS that needs to be monitored, so it’s drafted to supply a serial port for the purpose. This PC may in fact be getting its own power from some other UPS. This is not a problem for the set-up.
The first system ("mixed") is a Primary for UPS 1, but is only monitoring UPS 2. The other systems are Secondaries of UPS 2.
The current list of hardware supported by NUT can be viewed here.
This software has been reported to run on:
There is also a port of the client-side monitoring to Windows called WinNUT. Windows users may be able to build it directly with Cygwin.
Your system will probably run it too. You just need a good C compiler and possibly some more packages to gain access to the serial ports. Other features, such as USB / SNMP / whatever, will also need extra software installed.
Success reports are welcomed to keep this list accurate.