Example: Configuring Option 82

As shown in Figure 27, the DHCP relay agent (Switch A) replaces Option 82 in DHCP requests before forwarding them to the DHCP server (Switch B).

• The Circuit ID sub-option is company001.

• The Remote ID sub-option is device001.

To use Option 82, you must also enable the DHCP server to handle Option 82.

	IMPORTANT: By default, interfaces on the device are disabled (in ADM or Administratively Down state). To have an interface operate, you must use the undo shutdown command to enable that interface.

# Specify IP addresses for the interfaces. (Details not shown.)

# Enable DHCP.

<SwitchA> system-view
[SwitchA] dhcp enable

# Enable the DHCP relay agent on VLAN-interface 10.

[SwitchA] interface vlan-interface 10
[SwitchA-Vlan-interface10] dhcp select relay

# Specify the IP address of the DHCP server.

[SwitchA-Vlan-interface10] dhcp relay server-address 10.1.1.1

# Configure the handling strategies and padding content of Option 82.

[SwitchA-Vlan-interface10] dhcp relay information enable
[SwitchA-Vlan-interface10] dhcp relay information strategy replace
[SwitchA-Vlan-interface10] dhcp relay information circuit-id string company001
[SwitchA-Vlan-interface10] dhcp relay information remote-id string device001