Operation Manual – DHCPH3C S5600 Series Ethernet Switches Chapter 3 DHCP Relay Agent Configuration3-4Note:Request packets sent by a DHCP client fall into two categories: DHCP-DISCOVERpackets and DHCP-REQUEST packets. As DHCP servers coming from differentmanufacturers process DHCP request packets in different ways (that is, some DHCPservers process Option 82 in DHCP-DISCOVER packets, whereas the rest processOption 82 in DHCP-REQUEST packets), a DHCP relay agent adds Option 82 to bothtypes of packets to accommodate to DHCP servers of different manufacturers.3.2 Configuring the DHCP Relay AgentNote:If a switch belongs to an IRF fabric, you need to enable the UDP Helper function on itbefore configuring it as a DHCP relay agent.3.2.1 DHCP Relay Agent Configuration Task ListComplete the following tasks to configure the DHCP relay agent:Task RemarksEnabling DHCP RequiredCorrelating a DHCP Server Group with a Relay Agent Interface RequiredConfiguring DHCP Relay Agent Security Functions OptionalConfiguring the DHCP Relay Agent to Support Option 82 Optional3.2.2 Enabling DHCPMake sure to enable DHCP before you perform other DHCP relay-relatedconfigurations, since other DHCP-related configurations cannot take effect with DHCPdisabled.Follow these steps to enable DHCP:
