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Backup Latency Interval
On domain controllers running Windows Server 2003 with Service Pack 1 (SP1), a new event message, event ID 2089, provides the backup status of each directory partition that a domain controller stores, including application directory partitions. Specifically, event ID 2089 is logged in the Directory Service event log when partitions in the Active Directory forest are not backed up with sufficient frequency, that is, within a backup latency interval. The value for the backup latency interval is stored as a REG_DWORD value in the Backup Latency Threshold (days) entry in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic es\NTDS\Parameters.
By default, the value of Backup Latency Threshold (days) is half the value of the tombstone lifetime of the forest. If halfway through the tombstone lifetime a directory partition has not been backed up, event ID 2089 is logged in the Directory Service event log and continues daily until the directory partition is backed up.
This event serves as a warning to administrators and monitoring applications to make sure that domain controllers are backed up before the tombstone lifetime expires. However, it is recommended that you take backups at a much higher frequency than the default value of Backup Latency Threshold (days).
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