[CentOS] Odd issue with custom udev rule at boot

James A. Peltier jpeltier at sfu.ca
Thu Jun 16 15:26:45 UTC 2011


----- Original Message -----
| James A. Peltier wrote:
| 
| > BTW: Can anyone try this to see if it is in fact a bug or not?
| >
| > Create a file called
| >
| > /etc/udev/rules.d/99-udev-override.rules
| >
| > that contains
| >
| > KERNEL=="tty[A-Z]*", GROUP="some_other_group_than_uucp",
| > MODE="0660", OPTIONS="last_rule"
| >
| > with mode of 0644 reboot and confirm that the group permissions
| > change or not. If you change the mode however you will see that the
| > mode *does* change.
| 
| Works for me.
| 
| Before:
| 
| # ls -l /dev/ttyS*
| crw-rw---- 1 root uucp 4, 64 Jun 15 16:16 /dev/ttyS0
| crw-rw---- 1 root uucp 4, 65 Jun 15 16:16 /dev/ttyS1
| crw-rw---- 1 root uucp 4, 66 Jun 15 16:16 /dev/ttyS2
| crw-rw---- 1 root uucp 4, 67 Jun 15 16:16 /dev/ttyS3
| 
| Created /etc/udev/rules.d/99-udev-override.rules containing:
| 
| KERNEL=="tty[A-Z]*", GROUP="users", MODE="0660", OPTIONS="last_rule"
| 
| After reboot:
| 
| # ls -l /dev/ttyS*
| crw-rw---- 1 root users 4, 64 Jun 16 10:45 /dev/ttyS0
| crw-rw---- 1 root users 4, 65 Jun 16 10:45 /dev/ttyS1
| crw-rw---- 1 root users 4, 66 Jun 16 10:45 /dev/ttyS2
| crw-rw---- 1 root users 4, 67 Jun 16 10:45 /dev/ttyS3
| 
| However, if I use a group name that isn't in /etc/groups (but is
| defined
| in say NIS), then the group is set to root after a reboot - but using
| the GID of that group works.
| 
| James Pearson

AHA!  We use NIS here and I didn't even think that it wouldn't set the GROUP properly if it couldn't resolve it properly.  James, you're brilliant! That fixed it. 

:)


-- 
James A. Peltier
IT Services - Research Computing Group
Simon Fraser University - Burnaby Campus
Phone   : 778-782-6573
Fax     : 778-782-3045
E-Mail  : jpeltier at sfu.ca
Website : http://www.sfu.ca/itservices
          http://blogs.sfu.ca/people/jpeltier





More information about the CentOS mailing list