Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm attempting to make the device permissions on a hard drive(/dev/sdb) persistent for a particular group in RHEL5. Can anyone point me to to a proper KERNEL line in /etc/udev/rules that would work that attempts the following?

KERNEL=="sdb", NAME="%k", GROUP="group", MODE="666", OPTIONS="last_rule"
share|improve this question

migrated from Oct 19 '10 at 16:12

This question came from our site for professional and enthusiast programmers.

up vote 0 down vote accepted

That rule looks good.

Have you put it in a file in /etc/udev/rules.d before 50-udev.rules? Then did you reboot or run /sbin/udevcontrol reload_rules and then udevtrigger?

You can test it like so: udevtest /block/sdb

Edit: Here is an example that worked for me. In /etc/udev/rules.d/10-local.rules:

KERNEL=="ttyS0", NAME="%k", GROUP="adm", MODE="666", OPTIONS="last_rule"

Ran udevcontrol reload_rules then udevtrigger --verbose. Result:

crw-rw-rw- 1 root adm 4, 64 Oct 18 16:16 /dev/ttyS0


# udevtest /class/tty/ttyS0
main: looking at device '/class/tty/ttyS0' from subsystem 'tty'
udev_node_add: creating device node '/dev/ttyS0', major = '4', minor = '64', mode = '0666', uid = '0', gid = '4'

Edit2: Also you can run udevcontrol log_priority=debug to get more info reported via syslog.

share|improve this answer
It's been some time since I required this, and I can't quite remember how I solved it. But thanks for the info about udevcontrol. – mnology Oct 20 '10 at 21:16

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.