By default, a Windows Server 2008 DHCP server automatically updates A and PTR records for DHCP clients that request a dynamic DNS update.To Configure Your DHCP Server to Perform Dynamic DNS Updates1. In Server Manager, expand Roles, and then expand DHCP Server.
2. Expand the server name, right-click IPv4, and then click Properties.
3. Click the DNS tab. Select Enable DNS Dynamic Updates According To The Settings Below.
4. To allow the DHCP server to remove resource records after a DHCP lease expires, select the Discard A And PTR Records When A Lease Is Deleted check box.
5. To perform dynamic DNS updates for client computers that are not capable of performing their own updates, select the Dynamically Update DNS A And PTR Records For DHCP Clients That Do Not Request Updates check box. Windows 2000 and all later versions of Windows can perform their own dynamic DNS updates. Click OK.
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