Exclusion Ranges

An exclusion range is a set of one or more IP addresses, included within the range of a defined scope, that you do not want to lease to DHCP clients. Exclusion ranges assure that the server does not offer to DHCP clients on your network any addresses in these ranges. For example two exclusion ranges being configured for a new scope, one of which consist of only one IP address. By setting an exclusion for these addresses, you specify that DHCP clients are never offered these addresses when they request a lease from the server.

You can also use exclusion ranges at the edges of ranges. For example, you can define a scope's range as 192.168.1.1 through 192.168.1.254 and then define an exclusion range of 192.168.1.1 through 192.168.1.10 to accommodate the servers within the subnet that have IP addresses that are configured manually (statically).

Tip Because Windows Server 2003 recommends that a computer running the DHCP service have its IP address statically configured, be sure the server computer has its IP address either outside of, or excluded from, the range of the scope.

After you define a DHCP scope and apply exclusion ranges, the remaining addresses form the available address pool within the scope. Pooled addresses are eligible for dynamic assignment by the server to DHCP clients on your network.