dhcp-relay information

Enables the DHCP relay agent (which forwards DHCPv4 messages between DHCP clients and DHCP servers) to provide network security by checking for and adding DHCPv4 option 82 information that identifies from where the DHCP request came. Option 82 sub-options include the DHCP client's circuit ID and a remote ID, providing trusted location information for the remote client. DHCP relay information can be enabled at the VLAN level or at the interface level.
Syntax
dhcp-relay information {enable | circuit-id circuit-id |remote-id remote-id}
no dhcp-relay information {enable | circuit-id circuit-id |remote-id remote-id}
Command Default
DHCP packets are forwarded without regard for the client's network location information in the DHCP messages.
Parameters
enable

Enables DHCP relay information on the specified VLAN or interface. This allows the user to configure circuit-id and remote-id for the VLAN.

circuit-idcircuit-id
Configures the client device circuit-id to be added. The circuit-id may be up to 63 characters in length.
remote-idremote-id
Configures the client device remote-id to be added. The remote-id may be up to 63 characters in length.
Modes

Interface configuration mode.

Usage Guidelines

This command is supported for ICX 8200 devices only.

The no form of the command will disable the DHCP relay information functionality on the specified VLAN or interface.

Examples

The following example enables DHCP relay information, and defines the circuit-id and remote-id, on the specified VLAN. The show command is used to confirm the configuration on the VLAN.

device# config terminal
device(config)# vlan 1000
device(config-vlan-1000)# dhcp-relay information enable
device(config-vlan-1000)# dhcp-relay information circuit-id circuit01
device(config-vlan-1000)# dhcp-relay information remote-id remote01
device(config-vlan-1000)# exit
device# show running-config vlan 1000
vlan 1000 by port
 tagged ethe 1/1/11 ethe 1/1/23 
 dhcp-relay information enable
 dhcp-relay information circuit-id circuit01
 dhcp-relay information remote-id remote01

The following example enables DHCP relay information, and defines the circuit-id and remote-id, on the specified interface. The show command is used to confirm the configuration on the interface. 

device(config)# interface ethernet 1/1/23
device(config-if-e1000-1/1/23)# dhcp-relay information enable
device(config-if-e1000-1/1/23)# dhcp-relay information circuit-id circuit02
device(config-if-e1000-1/1/23)# dhcp-relay information remote-id remote02
device(config-if-e1000-1/1/23)# exit
device# show running-config interface ethernet 1/1/23
interface ethernet 1/1/23
 dhcp-relay information enable
 dhcp-relay information circuit-id circuit02
 dhcp-relay information remote-id remote02
History
Release version Command history
10.0.20 This command was introduced.
Parent topic: Commands D through H