110Allocating different IP addresses to DHCP clientswith the same MACTraditionally, the DHCP server identifies DHCP clients based on their MAC addresses. Each MACaddress can be bound to only one IP address. However, DHCP clients that have the same MACaddress exist in the network, and each client requires an IP address. You can enable this feature toallocate different IP addresses to such clients.This feature enables the DHCP server to use the following methods to identify the DHCP clients thathave the same MAC address:• If a DHCP snooping device or a DHCP relay agent exist, you must enable the DHCP snoopingdevice or the DHCP relay agent to support Option 82. The DHCP server identifies a DHCPclient by the MAC address of the client and the Option 82 in the DHCP request.• If no DHCP snooping device or DHCP relay agent is on the network, the DHCP server identifiesa DHCP client by the combination of the following information:{ The MAC address of the client.{ The interface name in the DHCP request.{ The VLAN information of the receiving interface.To allocate different IP addresses to DHCP clients with the same MAC address:Step Command Remarks1. Enter system view. system-view N/A2. Enable allocation ofdifferent IP addresses toDHCP clients with thesame MAC address.dhcp server multi-ip per-macenableBy default, allocation ofdifferent IP addresses to DHCPclients with the same MACaddress is disabled.Enabling random IP address allocationBy default, the DHCP server tries to allocate the same IP address as the previous allocation to thesame user.With this feature enabled, the DHCP server tries to allocate a new IP address to a user every time theuser acquires an IP address. This feature is applicable to the scenarios where a user must obtaindifferent IP addresses for each IP address acquisition.To enable random IP address allocation:Step Command Remarks1. Enter system view. system-view N/A2. Enter DHCP addresspool view. dhcp server ip-pool pool-name By default, no DHCPaddress pool exists.3. Enable random IPaddress allocation. allocate-new-ip enableBy default, random IPaddress allocation isdisabled.Configuring IP address conflict detectionBefore assigning an IP address, the DHCP server pings that IP address.
