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Section: NUT Manual (5) Updated: 12/24/2010
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ups.conf - UPS definitions for Network UPS Tools  


This file is read by the driver controller upsdrvctl(8), the UPS drivers that use the common core (see nutupsdrv(8), and upsd(8)). The file begins with global directives, and then each UPS has a section which contains a number of directives that set parameters for that UPS.

A UPS section begins with the name of the UPS in brackets, and continues until the next UPS name in brackets or until EOF. The name "default" is used internally in upsd, so you can't use it in this file.

You must define the driver and port elements for each entry. Anything after that in a section is optional. A simple example might look like this:

        driver = blazer_ser
        port = /dev/ttyS0
        desc = "Web server UPS"

A slightly more complicated version includes some extras for the hardware-specific part of the driver:

        driver = apcsmart
        port = /dev/cua00
        cable = 940-0095B
        sdtype = 2
        desc = "Database server UPS"

In this case, the apcsmart(8) driver will receive variables called "cable" and "sdtype" which have special meanings. See the man pages of your driver(s) to learn which variables are supported and what they do.  



Optional. The driver will chroot(2) to this directory during initialization. This can be useful when securing systems.


Optional. Path name of the directory in which the UPS driver executables reside. If you don't specify this, the programs look in a built-in default directory, which is often /usr/local/ups/bin.


Optional. Same as the UPS field of the same name, but this is the default for UPSes that don't have the field.


Optional. The status of the UPS will be refreshed after a maximum delay which is controlled by this setting. This is normally 2 seconds. This may be useful if the driver is creating too much of a load on your system or network.


Optional. If started as root, the driver will setuid(2) to the user id associated with username.



Required. This specifies which program will be monitoring this UPS. You need to specify the one that is compatible with your hardware. See nutupsdrv(8) for more information on drivers in general and pointers to the man pages of specific drivers.


Required. This is the serial port where the UPS is connected. On a Linux system, the first serial port usually is /dev/ttyS0. On FreeBSD and similar systems, it probably will be /dev/cuaa0.


Optional. When you have multiple UPSes on your system, you usually need to turn them off in a certain order. upsdrvctl shuts down all the 0s, then the 1s, 2s, and so on. To exclude a UPS from the shutdown sequence, set this to -1.

The default value for this parameter is 0.


Optional. This allows you to set a brief description that upsd will provide to clients that ask for a list of connected equipment.


Optional. When you specify this, the driver skips the port locking routines every time it starts. This may allow other processes to seize the port if you start more than one accidentally.

You should only use this if your system won't work without it.

This may be needed on Mac OS X systems.


Optional. This can be set as a global variable above your first UPS definition and it can also be set in a UPS section. This value controls how long upsdrvctl will wait for the driver to finish starting. This keeps your system from getting stuck due to a broken driver or UPS.

The default is 45 seconds.

All other fields are passed through to the hardware-specific part of the driver. See those manuals for the list of what is allowed.  


upsdrvctl(8) uses this file to start and stop the drivers.

The drivers themselves also obtain configuration data from this file. Each driver looks up its section and uses that to configure itself.

upsd(8) learns about which UPSes are installed on this system by reading this file. If this system is called "doghouse" and you have defined a UPS in your ups.conf called "snoopy", then you can monitor it from upsc(8) or similar as "snoopy@doghouse".  


upsd(8), nutupsdrv(8), upsdrvctl(8)  

Internet resources

The NUT (Network UPS Tools) home page:



Internet resources

This document was created by man2html, using the manual pages.
Time: 22:00:23 GMT, April 16, 2011