HP-UX Directory Server 8.1 administrator guide

3. Restart the Directory Server to apply the changes. In the Tasks tab, select Restart the
Directory Server.
NOTE:
All attributes used in referential integrity must be indexed for presence and equality; not indexing
those attributes results poor server performance for modify and delete operations. For more
information about checking and creating indexes, see “Creating indexes”.
3.6 Assigning and managing unique numeric attribute values
Some entry attributes require having a unique number, such as uidNumber and gidNumber.
The Directory Server can automatically generate and supply unique numbers for specified
attributes using the Distributed Numeric Assignment (DNA) Plug-in.
3.6.1 Overview of unique number assignments
Many situations require a unique numeric attribute, such as UID/GID numbers or PIN numbers.
The server uses DNA Plug-in instances to specify the attributes for which to generate the numbers,
so whenever that attribute is added to an entry, the unique value can be assigned.
3.6.1.1 How the Directory Server manages unique numbers
The issue with assigning unique numbers is not with generating the numbers but in effectively
managing numbers so that there are not any conflicts with other assigned numbers when entries
are replicated and that every server has a sufficient range of numbers to assign.
The DNA Plug-in for a server assigns a range of available numbers that the Directory Server
instance can issue. The range definition is very simple and is set by two attributes: the server's
next available number (the low end of the range) and its maximum value (the top end of the
range). The initial bottom range is set when the plug-in instance is configured. After that, the
bottom value is updated by the plug-in. By breaking the available numbers into ranges, the
servers can all continually assign numbers without overlapping with each other.
132 Creating directory entries