6-10Figure 6-3 Network diagram for DHCP relay agentConfiguration procedure# Specify IP addresses for the interfaces (omitted).# Enable DHCP. system-view[SwitchA] dhcp enable# Add DHCP server 10.1.1.1 into DHCP server group 1.[SwitchA] dhcp relay server-group 1 ip 10.1.1.1# Enable the DHCP relay agent on VLAN-interface 1.[SwitchA] interface vlan-interface 1[SwitchA-Vlan-interface1] dhcp select relay# Correlate VLAN-interface 1 to DHCP server group 1.[SwitchA-Vlan-interface1] dhcp relay server-select 1Because the DHCP relay agent and server are on different subnets, you need to configure a staticroute or dynamic routing protocol to make them reachable to each other.DHCP Relay Agent Option 82 Support Configuration ExampleNetwork requirementsz As shown in Figure 6-3, Enable Option 82 on the DHCP relay agent (Switch A).z Configure the handling strategy for DHCP requests containing Option 82 as replace.z Configure the padding content for the circuit ID sub-option as company001 and for the remote IDsub-option as device001.z Switch A forwards DHCP requests to the DHCP server after replacing Option 82 in the requests,so that the DHCP clients can obtain IP addresses.
