udev

This page is intended to list some udev-related tools and tricks i commonly forget.

General udev-related tools

As a first step, it might be useful to use

udevadm monitor

while plugging in the device.

USB devices

Use lsusb to check if your device shows up. If it does, you can use the bus- and device number to find more information about the device:

lsusb -s <Bus>:<Device> -v

You might also check /dev/bus/usb/<Bus>/<Device> to check access permissions. You can get udev-related information (especially attributes) by using

udevadm info --attribute-walk --name=<Device path>

Writing rules files

In general: Beware that you can only use attributes from the same parent of a device in one rule. If you want to use attributes from different levels in one rule, you have to use multiple rules and GOTO.

Common rules

For many devices, it makes sense to assign devices to the dialout group with corresponding access rights. This can be done using rules such as

SUBSYSTEM=="usb", [...], GROUP="dialout", MODE="0660"