The alias entry and the entry it represents must be in the same data store. For bind and search operations, you can specify that the directory should translate an alias DN to the DN of the actual entry. This is known as dereferencing the alias. For other operations, you need to treat the alias entry as an ordinary entry and not dereference it, for example, to modify the RDN of the alias entry itself, not of the aliased object. Alias Entries and Searching The result of a search or read operation involving an alias entry differs depending on whether or not you dereference the alias.
All operations apply to the entry with the given DN, even though the entry is an alias entry.
This is the default setting. Dereference alias when finding base object-The base object identifies the top of the subtree of entries to be searched. This setting means that if you specify an alias as the base object it will be dereferenced, but no other aliases encountered during the search are dereferenced. Dereference alias when searching-If the operation being carried out is a search, all alias entries specified or used in the search are dereferenced. If the result of the search is an alias entry, the aliased object is returned to the user, not the alias entry.