The latest filesystem package provides two new groups by default: audio and optical.
These are provided for users who have sound cards and/or DVD/CD-RW devices in their computers. To allow your regular user to access the device, simply add yourself to the audio and optical groups, and logout and back in.
# gpasswd -a johndoe audio # gpasswd -a johndoe optical
The latest udev.permissions file will grant permissions to sound devices by default, but you're required to take an extra step to set up permissions on your DVD/CD-RW drive. Since Arch doesn't know which hdX device is your optical drive, the default udev.permissions does not assign any of them to the optical group. To point it to the right drive, create a file called /etc/udev/permissions.d/00.permissions (you shouldn't edit the existing udev.permissions, it may be overwritten in the future) and add the following line:
hdc:root:optical:0660
(obviously, we're using /dev/hdc as an example here)
If you'd like to have a /dev/dvd symlink to the proper device, you can create a /etc/udev/rules.d/00.rules file that has something like the following:
KERNEL="hdc", NAME="hdc", SYMLINK="dvd"
Then reboot or restart udev:
# /etc/start_udev # mount /dev/pts # mount /dev/shm
I know many of you probably already have an audio group or the like. If you do, you can continue using your own group and ignore these instructions.
If you'd like to learn more about uDev rules and their power, check out this article.