2-3The DHCP server assigns an IP address to the client in the following order from an interface addresspool or a global address pool:3) If there is an address pool where an IP address is statically bound to the MAC address or ID of theclient, the DHCP server will select this address pool and assign the statically bound IP address tothe client.4) Otherwise, the DHCP server observes the following principles to select a dynamic address pool.z If the client and the server reside in the same network segment, the smallest address pool thatcontains the IP address of the receiving interface will be selected.z If the client and the server do not reside in the same network segment (that is, a DHCP relay agentis in-between), the smallest address pool that contains the IP address specified in the giaddr fieldof the client’s request will be selected.z If no assignable IP address is available in the selected address pool, the DHCP server will notassign any IP address to the client because it cannot assign an IP address from the parent addresspool to the client.DHCP IP Address PreferencesA DHCP server assigns IP addresses in interface address pools or global address pools to DHCPclients in the following sequence:1) IP addresses that are statically bound to the MAC addresses of DHCP clients or client IDs.2) The IP address that was ever assigned to the client3) The IP address designated by the Option 50 field in a DHCP-DISCOVER message4) The first assignable IP address found in a proper DHCP address pool5) If no IP address is available, the DHCP server queries lease-expired and conflicted IP addresses. Ifthe DHCP server finds such IP addresses, it assigns them; otherwise the DHCP server does notassign an IP address.DHCP Server Configuration Task ListComplete the following tasks to configure the DHCP server:Task RemarksEnabling DHCP RequiredConfiguring the Global Address Pool BasedDHCP ServerConfigure addresspool based DHCPserver Configuring the Interface Address Pool BasedDHCP ServerOne of the two options isrequiredConfiguring DHCP Server Security Functions OptionalConfiguring DHCP Accounting Functions OptionalEnabling the DHCP Server to Process Option 82 OptionalEnabling DHCPYou need to enable DHCP to make other related configurations take effect.Follow these steps to enable DHCP:
