Archiver Obtaining List of Domain Controllers
If the archiver is configured to use domain group security, the data archiver obtains the list of primary and backup domain controllers at archiver startup. If a domain controller is not available at that time or if you add new domain controllers, they are not seen by the archiver until the next time the archiver is restarted. For example, if your backup domain controller was not available on archiver startup, the archiver will not fail over to the backup domain controller for user authentication.
For more information, refer to the Working with Security section in Online Help.