nut/scripts/udev/README

Desc: Udev script for NUT USB and IPMI drivers
File: scripts/udev/README
Date: 25 July 2011
Auth: Arnaud Quette <aquette.dev@gmail.com>

This document introduces the Linux udev script for NUT USB
drivers (usbhid-ups, bcmxcp_usb, tripplite_usb, ...) and IPMI driver
(nut-ipmipsu).

These are needed on Linux systems running udev (recommended
as of kernel 2.6.3, and mandatory as of 2.6.14 and higher).

This script ensure that the right privileges are set on the
USB and IPMI devices files to allow the NUT driver to operate (ie
allowing the nut user to read AND write to the device).

Note that the old style hotplug files, available in the
scripts/hotplug directory, are not needed if your kernel supports
udev.

Installation
------------

For most users, these files will be automatically installed in
/etc/udev (or /lib/udev) upon "make install", if that directory exists and if
the feature (USB and / or IPMI) has been enabled at configure time. You can
specify an alternate directory with ./configure --with-udev-dir=DIR.

Manual installation
-------------------

To install them manually, copy the rules file(s) to /etc/udev/rules.d
(or /lib/udev/rules.d on newer systems) using the command(s):

$ cp -f nut-usbups.rules /etc/udev/rules.d/52-nut-usbups.rules
$ cp -f nut-ipmipsu.rules /etc/udev/rules.d/52-nut-ipmipsu.rules

You will need to refresh the bus to avoid a reboot for these rules to be
active. You can do so using:

$ udevadm trigger --subsystem-match=usb_device

For USB devices, you can then plug your UPS USB cord, or unplug / replug
it to refresh the device permission, and start NUT.