+A: udev can be placed in initramfs and run for every device that is found.
+ udev can also populate an initial /dev directory from the content of /sys
+ after the real root is mounted.
+
+Q: Can I use udev to automount a USB device when I connect it?
+A: Technically, yes, but udev is not intended for this. All major distributions
+ use HAL (http://freedesktop.org/wiki/Software_2fhal) for this, which also
+ watches devices with removable media and integrates into the desktop software.
+
+ Alternatively, it is easy to add the following to fstab:
+ /dev/disk/by-label/PENDRIVE /media/PENDRIVE vfat user,noauto 0 0
+
+ This means that users can access the device with:
+ $mount /media/PENDRIVE
+ and doen't have to be root, but will get full permissions on the device.
+ Using the persistent disk links (label, uuid) will always catch the
+ same device regardless of the actual kernel name.
+
+Q: Are there any security issues that I should be aware of?
+A: When using dynamic device numbers, a given pair of major/minor numbers may
+ point to different hardware over time. If a user has permission to access a
+ specific device node directly and is able to create hard links to this node,
+ he or she can do so to create a copy of the device node. When the device is
+ unplugged and udev removes the device node, the user's copy remains.
+ If the device node is later recreated with different permissions the hard
+ link can still be used to access the device using the old permissions.
+ (The same problem exists when using PAM to change permissions on login.)
+
+ The simplest solution is to prevent the creation of hard links by putting
+ /dev in a separate filesystem like tmpfs.