When creating a directory rule, select the criterion Net mask. The thin clients will then be sorted into automatically created directories according to IP address ranges. The name of the folder is determined through this bitwise operation:
Folder = IP address of the thin client AND net mask
As the target directory, select the device directory under which the subfolders for the IP address ranges are to be created.
Because this rule always applies, it is not a good idea to define a further rule. If the net mask rule sorts all devices into directories, no further rule is active.