Database Management

The following describes the administrative tasks for managing your DHCP database. To avoid high cost of ownership, these are performed by Windows 2000 automatically, but can also be done manually by the network administrator.

Record Management

There is no built-in limit to the number of records that a DHCP server can store. The size of the database depends on the number of DHCP clients on the network. The DHCP database grows over time as a result of clients starting and stopping on the network. Over time, as some DHCP client entries become obsolete and are deleted, some unused space remains.

Storage Space Management

To recover unused space, the DHCP database must be compacted. Windows 2000 dynamically compacts the database in an automatic background process during idle time after a database update. Although dynamic compacting greatly reduces the need for performing offline compaction, it does not fully eliminate it. Offline compaction reclaims the space more efficiently and should be performed at least once a month for large, busy networks with 1,000 or more DHCP clients. For smaller networks, manual compaction might be required only every few months.

Because the dynamic database compaction occurs in the background while the database is in use, you do not need to stop the DHCP server. However, for manual compacting, the DHCP server must be taken offline.

Database Backup

The DHCP database and related registry entries are automatically backed up at a specific interval. You can modify the default interval by changing the value of the BackupInterval entry in the following registry subkey:



Do not use a registry editor to edit the registry directly unless you have no alternative. The registry editors bypass the standard safeguards provided by administrative tools. These safeguards prevent you from entering conflicting settings or settings that are likely to degrade performance or damage your system. Editing the registry directly can have serious, unexpected consequences that can prevent the system from starting and require that you reinstall Windows 2000. To configure or customize Windows 2000, use the programs in Control Panel or Microsoft Management Console (MMC) whenever possible.