I suspect something like this is going on:
When you plug in the USB drive, hotplug detects the event and creates the device node.
When you are done with the USB drive, you unplug it and hotplug does not remove the device node. It's probably happening because you didn't umount the USB disk before removing it.
Try a test:
Plug the USB drive in and wait for the new device node to appear.
Manually umount the device, then unplug the USB drive.
Did the device node remain, or did it disappear?
You can also watch /etc/mtab for the appearance and disappearance of the USB device.
Then look in /etc/udev/rules.d/50-udev-rules. You may see something like this:
Code:
BUS="scsi", PROGRAM="/sbin/udev.get_persistent_device_name.sh", NAME="%k" SYMLINK="%c{1+}", MODE="0660", GROUP="disk"
BUS="usb", PROGRAM="/sbin/udev.get_persistent_device_name.sh", NAME="%k" SYMLINK="%c{1+}", MODE="0660", GROUP="disk"
BUS="ide", PROGRAM="/sbin/udev.get_persistent_device_name.sh", NAME="%k" SYMLINK="%c{1+}", MODE="0660", GROUP="disk"
BUS="ccw", PROGRAM="/sbin/udev.get_persistent_device_name.sh", NAME="%k" SYMLINK="%c{1+}", MODE="0660", GROUP="disk"
Or, those lines may refer to "/sbin/get-unique-drive-id.sh"; in which case, change the lines to read as above.