set protocols dhcp snooping vlan option82-policy

The set protocols dhcp snooping vlan option82-policy command configures how to handle the Option 82 field when receiving a DHCP Discover/Request/Release/Decline/Inform message with Option 82 on VLANs where DHCP snooping is enabled.

Command Syntax

set protocols dhcp snooping vlan <vlan-id> option82-policy <drop | keep | insert | replace>

Parameters

Parameter

Description

vlan <vlan-id>

Specifies a VLAN. The value is an integer that ranges from 1 to 4094.

option82-policy <drop | keep | insert | replace>

Specifies the policy for Option 82. The value could be drop, keep, insert or replace.

drop: drop the packet if have Option 82. If the received DHCP packets have no Option 82 values, the packets will be forwarded.
keep: Option 82 in the packet remains unchanged and forwarded.
insert: the existing Option 82 sub-options remain unchanged, and the non-existing Option 82 sub-options will be inserted with the value the administrator configured, then forward the packet to the DHCP server.
replace: The non-existing Option 82 sub-options, will be inserted with the value the administrator configured. The existing Option 82 sub-options will be replaced with the value administrator configured, and then forward the packet.

The default value is keep.

Usage Guidelines

Option 82 policy is used when receiving a DHCP Discover/Request/Release/Decline/Inform message from the DHCP client. When option82-policy is set to “insert” or “replace”, you can use the following commands to set the format of circuit ID and remote ID sub-options:

set protocols dhcp snooping option82 circuit-id <port-index | port-name | port-description>

set protocols dhcp snooping option82 remote-id <system-mac | hostname>

We can use the following table to summarize the Option 82 policy.

For details about how Option 82 is processed by the DHCP snooping and DHCP relay module, see Introduction to DHCP.

Example

Configure the Option 82 policy.

admin@Xorplus# set protocols dhcp snooping vlan 12 option82-policy insert