DNS can be used to provide names for network resources, as described in Chapter 12, "Networking Concepts for TCP/IP." However, DNS configuration is static. With DHCP, a host can easily have a different IP address if its lease expires or for other reasons, but there is no standard for updating DNS servers dynamically when IP address information changes. Therefore, DNS naming conflicts can occur if you are using DHCP for dynamic allocation of 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, such 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.