DHCP server and DNS updates

In the previous article, we have explained how to install the DHCP server in the Win system and how to set the relevant scope. Here we will mainly discuss the DNS update and DHCP update settings for the scope.

Set DNS updates for the scope

Dynamic DNS update for rented IP addresses is an advantage of DHCP, especially for low-level clients that cannot directly register DNS. Figure 15-10 shows the default settings of the DNS tab in the scope Properties window. The DHCP Properties window also has a DNS tab similar to this type. Server-level attributes provide default values for new scopes, while scope-level attributes are used to control the actions of scopes.

After you set the option to allow the DHCP server to send update information to the DNS server in the TCP/IP attribute window of the server, you should be careful to configure the DHCP server to use the master server, so that DNS updates do not need to be submitted by the secondary server to the primary server. Otherwise, the secondary server must submit the DNS update to the primary server. Please note that this feature can be completely disabled, or the DNS option can be updated only when the client requests. The DHCP server can identify different clients because the Microsoft DHCP Client sends the manufacturer information later.

There are options for DHCP to update DNS for all clients that are not determined to be able to update DNS by themselves. These clients refer to clients that provide full domain names to the DHCP server without using the recommended option 81. The windows 2000 client that uses this option is registered in the DNS domain specified by the full domain name.

When DHCP registers a client in DNS, As long as DNS security is implemented through Active Directory integration, it can be set as the owner of the DNS record. If the account of the machine running DHCP is a member of the DnsUpdateProxy group created in the Active Directory, the DHCP server will not automatically become the owner of the records it creates. However, if the machine account is not a member of the DnsUpdateProxy group, the DHCP server automatically becomes the record owner. Chapter 2 discusses these transactions. These transactions should be considered when updates are allowed in these environments.