Domain Name System (DNS) servers can be used to provide names for network resources. However, there is no current IETF specification for dynamically updating DNS servers such as when a DHCP client is dynamically configured with an IP address and other TCP/IP configuration parameters. Therefore, DNS naming conflicts can occur if you are using a DHCP server for dynamic assignment of client IP addresses.
This problem primarily affects systems that extend internetworking services to local network users. For example, a server acting as an anonymous FTP server or as an electronic mail gateway might require users to contact it using DNS names. In such cases, clients should have reserved leases with an unlimited duration.
For workstations in environments that do not require the computers to register in the DNS name space, DHCP dynamic allocation can be used without problems.