Configuring DHCP option 82
Configure the DHCP option 82 to enable the circuit ID to encode an agent-local identifier of the circuit from which a DHCP client-to-server packet is received. Configure the DHCP option 82 to enable the remote ID to encode the MAC address of the interface on which the packet is received. By default, the DHCP option 82 is disabled.
Before you begin
You must enable ip and dhcp-relay on the VLAN.
About this task
To configure the DHCP option 82 on a VLAN, you must enter the VLAN Interface Configuration mode.
To configure the DHCP option 82 on a brouter port, you must enter the GigabitEthernet Interface Configuration mode.
Procedure
Example
Switch:1> enable Switch:1# configure terminal Switch:1(config)# interface gigabitethernet 1/10
Enable the circuit ID:
Switch:1(config-if)# ip dhcp—relay circuitID
Enable the remote ID:
Switch:1(config-if)# ip dhcp-relay remoteID
Configure the circuit as trusted:
Switch:1(config-if)# ip dhcp-relay trusted
Show statistics for option 82, which is the relay agent information option:
Switch:1(config-if)# show ip dhcp-relay counters option82
Variable definitions
Use the data in the following table to configure the DHCP option 82.
Variable |
Value |
---|---|
circuitID |
Enables the Circuit ID. |
remoteID |
Enables the Remote ID. |
trusted |
Sets the circuit as trusted. |
Use the data in the following table to use the show ip dhcp-relay counters option82 [vrf WORD <0–16>] [vrfids WORD <0–512>] command.
Variable |
Value |
---|---|
vrf WORD <0–16> |
Displays DHCP counters for a particular VRF. WORD <0–16> specifies the VRF name. |
vrfids WORD <0–512> |
Displays a DHCP forward path for a particular VRF. WORD <0–512> specifies the VRF ID. |