18.4. ACI Evaluation

To evaluate the access rights to a particular entry, the server creates a list of the ACIs present on the entry itself and on the parent entries back up to the top level entry stored on the Directory Server. ACIs are evaluated across all databases for a particular instance but not across different instances.
Directory Server evaluates this list of ACIs based on the semantics of the ACIs, not on their placement in the directory tree. This means that ACIs that are close to the root of the directory tree do not take precedence over ACIs that are closer to the leaves of the directory tree.
In Directory Server, the deny permission in ACIs take precedence over the allow permission. For example, if you deny write permission at the directory's root level, none of the users can write to the directory, regardless if an other ACI grants this permission. To grant a specific user write permissions to the directory, you have to add an exception to the original denying rule to allow the user to write in that directory.

Note

For improved ACIs, use fine-grained allow rules instead of deny rules.