Tip:Back Up and Restore the DHCP Database
DHCP servers store DHCP lease and reservation information in database files. By default, these files are stored in the %SystemRoot%\System32\DHCP directory. The key files in this directory are used as follows:
Backing Up the DHCP Database
The Backup directory in the %SystemRoot%\System32\DHCP folder contains backup information for the DHCP configuration and the DHCP database. By default, the DHCP database is backed up every 60 minutes automatically. To manually back up the DHCP database at any time, follow these steps:
1. In the DHCP console, right-click the server you want to back up, and then click Backup.
2. In the Browse For Folder dialog box, select the folder that will contain the backup DHCP database, and then click OK.
Registry keys that control the location and timing of DHCP backups, as well as other DHCP settings, are located under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\DHCPServer\Parameters.
The following keys control the DHCP database and backup configuration:
Restoring the DHCP Database from Backup
In the case of a server crash and recovery, you might need to restore and then reconcile the DHCP database. To force DHCP to restore the database from backup, follow these steps:
1. If necessary, restore a good copy of the %SystemRoot%\System32\DHCP\Backup directory from the archive. Afterward, start the DHCP console, right-click the server you want to restore, and then click Restore.
2. In the Browse For Folder dialog box, select the folder that contains the backup you want to restore, and then click OK.
3. During restoration of the database, the DHCP Server service is stopped. As a result, DHCP clients are temporarily unable to contact the DHCP server to obtain IP addresses.