Udev is a Linux process that manages device file entries under /dev

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31
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3answers
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Why are network interfaces not in /dev like other devices?

I'm mostly curious, but why aren't network interfaces in /dev? Are there any other kinds of devices that aren't represented as a node under /dev?
30
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5answers
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How can I detect when a monitor is plugged in or unplugged?

Is there any event that is triggered when I plug in or out an external monitor into the DisplayPort of my laptop? ACPID and UDEV don't react at all. I'm using onboard graphics on an intel chip. Here ...
24
votes
4answers
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How to reload udev rules without reboot?

How should one reload udev rules, so that newly created one can function? I'm running Arch Linux, and I don't have a udevstart command here. Also checked /etc/rc.d, no udev service there.
23
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2answers
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Why do some Linux distributions still have /dev/ttyS0, ttyS1, etc., even though newer computers don't have such a serial port?

Many new laptop and desktop computers do not have 9-pin/25-pin serial ports. Why do many Linux distributions still contain /dev/ttyS0, dev/ttyS1 device files? Since udev can create the device files ...
22
votes
5answers
7k views

A tool for automatically applying RandR configuration when external display is plugged in

is there a tool which enables one to: remember current RandR configuration (position, orientation, resolution etc) on per-monitor basis, automatically apply last known good configuration as soon as ...
17
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1answer
8k views

How to assign USB driver to device

This question is two-fold: First, how do you manually detach a driver from a USB device and attach a different one? For example, I have a device that when connected automatically uses the ...
16
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2answers
10k views

How to run custom scripts upon USB device plug-in?

What is the state-of-the-art method for automatically executing custom scripts upon USB device plug-in under current Linux distributions like Debian/CentOS/Fedora? For example if you want to ...
9
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3answers
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Fake serial number of USB device

I have a mobile phone connected to my PC via USB. When viewing the device info using sudo udevadm info --attribute-walk the product and vendor id's show up fine, but there is no ATTR{serial}. An ...
8
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2answers
213 views

How can I find available network interfaces?

This is in regard to linux, but if anyone knows of a general *nix method that would be good. I booted a system yesterday with an ethernet cable plugged in. "NetworkManager" is not installed, so once ...
8
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2answers
4k views

In which log should I check for udev errors?

I've written a udev rule which is run each time my device is mounted/dismounted. However, in which Linux (Debian) error log should I check when debugging such rules?
8
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2answers
513 views

What's the difference between udev and hald?

I'm just beginning to dive into the internals of Linux, and I was wondering what the difference is between udev and the hal daemon. From what I gather, both seem to be responsible for managing hot ...
7
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2answers
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How can I hide messages of udev?

When I plug in a usbhub (7 sticks in) udev displays a lot of messages in console. Can I hide these messages or send them to /dev/null?
7
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1answer
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Understand output of `udevadm info -a -n /dev/sdb`

I plug an external HDD into my laptop. I try to find out the information by $ udevadm info -a -n /dev/sdb Udevadm info starts with the device specified by the devpath and then walks up the chain of ...
7
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1answer
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Suggestions needed for udev, udisks, autofs, notification setup for a complete automounting solution on Linux

Continuing on Automounting plugged devices in linux, which left things a bit basic. Running Gentoo, I'm automounting a combination of local and network devices on my laptop with autofs-5.0.4-r5. Doing ...
6
votes
3answers
77 views

Udev- How do I find out which subsystem a device belongs to?

For example, I have device /dev/sdb. How do I find out it's udev subsystem?
6
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2answers
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mknod permanent in archlinux

I have a custom kernel module (on ArchLinux) that I can load manually and interact with. What I would like to do is have it loaded at boot time. So far I have managed to get the device appear in ...
6
votes
2answers
1k views

Auto-run script when Wifi card is plugged in (udev)

I've been trying to use udev to make a Debian system run a bash script when a wireless card is connected. So far I created this file /etc/udev/rules.d/wifi-detect.rules: ACTION=="add", ...
6
votes
1answer
141 views

USB connect/disconnect notification

I use Linux Mint 13 MATE, and I'm trying to set up notifications when I plug/unplug devices. First of all, I found udev-notify package, but unfortunately it almost doesn't work for me: it works for ...
5
votes
3answers
200 views

How can I create a udev rule to mount a USB drive read only?

I'm trying to set a particular USB drive to always mount read only. If I plug it in, it is seen as sdb with a single partition, sdb1. Here are some relevant udevadm lines (not the entire output of ...
5
votes
3answers
600 views

Watch USB connections vendor id, product id, revision

I'd like to simply watch all devices added and removed from my system and view their USB vendor ID, product ID, and revision and other relevant information. How can I do this in Linux? Is there a ...
5
votes
2answers
112 views

/dev/disk/ lists disks, why /dev/net/ doesn't list network interfaces? [duplicate]

I know that udev manages devices in /dev and I expected to find information about available network cards (hardware) or at least network interfaces (software) there. ifconfig output shows me eth0 and ...
5
votes
1answer
2k views

Udev rule is not being used?

I'm setting up udev to handle my external USB hard drive when it gets plugged in and removed (no mounting yet). So far, I've made two new rules in /etc/udev/rules.d/10-local.rules to log ...
5
votes
1answer
408 views

What is the correct way to write a udev rule to stop a service under systemd

I'm running Arch Linux, and I have a udev rule which starts a service when a device is inserted. In this case, it dials a connection when a 3G modem is plugged in. KERNEL=="ttyUSB*", ...
5
votes
1answer
1k views

How do I disable udevd in systemd?

I'm trying to boot a Fedora Rawhide LXC container from a Fedora 16 host, and it's not working - systemd just keeps dropping into emergency mode. Because udevd doesn't work in LXC containers, I thought ...
5
votes
1answer
171 views

trigger udev rules from systemd

I have one of those hdds, that have a very aggressive power management. To prevent load cycles from rising in to critical numbers I wrote an udev rule: SUBSYSTEM=="block", SUBSYSTEMS=="scsi", ...
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2answers
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Making UDEV ignore certain devices during boot.

I'm trying to make UDEV stop mounting one of my devices at boot time, and I've created a rule in /etc/udev/rules.d/ called 1-myblacklist.rules. All the rule does is matches the device by kernel ...
4
votes
3answers
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Why is pcmanfm such a headache when it comes to mounting filesystems?

If I would have known how much 'customization' it takes to get LXDE and its default file manager, pcmanfm, just working, I would probably have never chosen to try it. I've got a problem. Lots of ...
4
votes
1answer
135 views

Difference between /dev and /sys/class?

What is the difference between the device representation in /dev between the one in /sys/class? Is one prefered over the other? Is there something one offers and the other doesn't?
4
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4answers
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UDEV rule when USB flash drive is unplugged

I wrote a rule to automount my USB stick to certain folder but when I unplug it the folder still mounted and when I ls there I see a lot of errors like: Directory bread (block: NNNN) failed I tried ...
4
votes
2answers
3k views

Permanently changing the ownership (or group) of LVM volume

How can I permanently change the ownership (or at least the group) of a LVM volume? I figured that I have to use udev, but I don't know how the rule should look like? Let's say I want to change the ...
4
votes
1answer
2k views

Preventing mounting some partition by user (gnome+udisk)

I'd like to prevent automounting one partition (known UUID etc. ) on one external harddrive. Others should be automounted. Distro is 'modern' (uses lots of beta software) and uses udisk+udev for ...
4
votes
2answers
252 views

Disable the external keyboard from a script

I have a udev rule for my external keyboard. I can catch events, and by running a script I can also reach udev env variables. Can I disable keyboard with udev? Or must I use a script to disable the ...
4
votes
1answer
673 views

How does udev create /dev/sr*? (Or: Which rule does create /dev/sr*?)

udev is responsible for populating /dev. It adds and removes device nodes to /dev dynamically based on rules/configs/scripts under /lib/udev and /etc/udev/. If I have a CDROM device node /dev/sr0 I ...
4
votes
2answers
135 views

How does udev get device numbers for the devices it creates?

Spun off from a small exchange in chat. One of the primary advantages of udev is that you don't have to worry about major and minor device number exhaustion anymore. But the devices created by udev ...
4
votes
2answers
1k views

udev rules don't appear to be working

I'm running Arch Linux on my server, and I need to let users of the group usb access my weather station. Here's my rule: /etc/udev/rules.d/usb-70.rules SYSFS {idVendor} == "1941", SYSFS {idProduct} ...
4
votes
1answer
244 views

udev rule for assigning known symlinks for identical usb serial devices

I have two (and possibly in the future, more) USB serial devices which are identical (down to the serial number, unfortunately) - they're actually BTC miners. Currently they end up as ttyUSBX where X ...
4
votes
1answer
1k views

Why doesn't this udev rule trigger upon removal of the device?

I have two mice, one which has an issue where the middle mouse button and button6 get triggered simultaneously. So I configured my ~/.Xmodmap to disable this button. At the same time, however, I ...
4
votes
1answer
1k views

Udev triggers are not firing on insert of CF card into USB card reader (anymore)

I've got a udev rule that triggers a shell script that copies photos off my CF card when I insert the card into my USB card reader. This worked fine for a while. But after a recent upgrade it has ...
4
votes
1answer
277 views

Swapping <esc> and <caps lock> in a way that persists with external keyboards

I have a file called ~/.speedswapper which contains the following: ! Swap caps lock and escape remove Lock = Caps_Lock keysym Escape = Caps_Lock keysym Caps_Lock = Escape add Lock = Caps_Lock ...
4
votes
1answer
829 views

Problems copying large files to USB drive

I've got some issues when copying larger files to my USB drive. First of all, my system stopped recognizing my USB drives automatically. I now have to run modprobe usb-storage in order for my USB ...
4
votes
1answer
713 views

Change permissions for LEDs (e.g. ThinkLight) with udev

/edit/ Getting the question more generic: How can I change the permissions to alter the state of a LED/light using udev? \edit\ I've got a Thinkpad and would like to use the ThinkLight (the ...
4
votes
1answer
84 views

lshw lists my drive but it has no /dev file

Ive just got a dedicated server which has 2x 1TB HDD. However when I type df -h I get the following: [root@sd-56537 ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/sda2 916G ...
3
votes
3answers
9k views

Automounting USB sticks on Debian

I'm running Debian Squeeze on a plug computer (so SSH only, no GUI) and what I'm trying to do is get it so that when a USB stick is plugged in, it gets automatically mounted. What I've done is ...
3
votes
2answers
118 views

Reference material about device management

Can anybody recommend materials about device management in the Linux environment? From the point where I insert a cdrom or usb device to the point where it is mounted in /media/somedir. I know that I ...
3
votes
1answer
107 views

What does it mean when something says that UNIX device files are static?

I've been reading up on udev. In the "overview" section, Wikipedia states that "unlike traditional Unix systems, where the device nodes in the /dev directory have been a static set of files, the Linux ...
3
votes
2answers
75 views

Is there a uniform way to discover information about devices?

UPD: Changed question title from manage devices to discover information about devices One of the frequent thing I do is look up info about devices on my systems. And I am constantly find myself ...
3
votes
2answers
154 views

how to include or add /dev with tar --one-file-system

I'm running tar on a complete remote filesystem using ssh -n <hostname> 'sudo tar -cpvzf - --one-file-system /' | cat > Bak.tar.gz This gave me a tarball. I tried importing this tarball ...
3
votes
2answers
3k views

building my own initrd, how to populate dev directory

I am trying to learn stuff about initrd. I have followed this tutorial to build my own initrd from scratch, and I installed busybox on it. Then I made an .iso from it with isolinux, so I could test it ...
3
votes
1answer
3k views

xrandr command not executed within shell command called from udev rule

I own a Thinkpad with an UltraBase (a docking station). My operating system is Ubuntu 10.10. Now, I would like to react on the "docking" event by setting the resolution of my external display ...
3
votes
1answer
1k views

script does not behave properly when called by acpi and udev events

I have the following files in /etc/acpi/events and /etc/udev/rules.d /etc/acpi/events/lidclose # Pass all events to our one handler script event=button/lid action=/etc/acpi/monitors.sh ...