A referral is a pointer that is used to redirect a client's request to another server. Typically, referrals indicate to the client application that the requested entry or branch of the directory tree is not present on the server but is located on another remote server or at another branch of the directory tree. The client must then perform the operation again on the remote server named in the referral.
Referrals can be used in the following cases:
When a client application requests an entry that does not exist on the local server, and the server has been configured to return the default referral.
When an entire suffix has been disabled for maintenance, backup, or security reasons. The server will return the referrals defined by that suffix.
When an object should be identified by different names. Referrals are useful to accommodate namespace changes.
When "search paths" are needed for collecting results from multiple servers.