To perform these procedures, you must be a member of the Administrators group, or you must have been delegated the appropriate authority.
To authorize the DHCP server in Active Directory Domain Services:
At the DHCP server computer, click Start, point to Administrative Tools, and then click DHCP.
In the DHCP console, right-click DHCP.
Select Manage authorized servers.
In the Manage Authorized Servers dialog box, click Authorize.
In the Authorize DHCP Server dialog box, type the name or IP address of the DHCP server, and then click OK.
You might also need to:
Remove other active DHCP servers from the network.
Reconfigure the Routing and Remote Access service. If Routing and Remote Access is set up incorrectly, it can act as a second DHCP server.
A DHCP server running Microsoft Small Business Server will not operate if another DHCP server is active on its network.
Detection of unauthorized DHCP servers requires the deployment of Active Directory Domain Services and the DHCP service. Other DHCP servers do not attempt to determine whether they are authorized by Active Directory Domain Services before offering IP address leases.