dhcp anti-attack check duplicate option

Function

The dhcp anti-attack check duplicate option command enables the device to check and discard DHCP messages with duplicate options.

The undo dhcp anti-attack check duplicate option command disables the device from checking and discarding DHCP messages with duplicate options.

By default, the device is disabled from checking and discarding DHCP messages with duplicate options.

Format

dhcp anti-attack check duplicate option [ option-start [ to option-end ] ] &<1-254>

undo dhcp anti-attack check duplicate option [ option-start [ to option-end ] ] &<1-254>

Parameters

Parameter	Description	Value
option-start [ to option-end ]	Specifies the option value. option-start: Specifies the start value of an option in a DHCP packet. option-end: Specifies the end value of an option in a DHCP packet.	The value is an integer in the range 1 to 254. For an option, the end value must be larger than the start value.

Parameter

Description

Value

option-start [ to option-end ]

Specifies the option value.

option-start: Specifies the start value of an option in a DHCP packet.
option-end: Specifies the end value of an option in a DHCP packet.

The value is an integer in the range 1 to 254. For an option, the end value must be larger than the start value.

Views

System view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

The dhcp anti-attack check duplicate option command applies to DHCP servers, DHCP relay agents, DHCP clients, and DHCP snooping-enabled devices. To discard DHCP messages with duplicate options 1 to 254, run the dhcp anti-attack check duplicate option command.

Prerequisites

DHCP has been enabled using the dhcp enable command.

Example

# Configure the device to discard DHCP messages with duplicate options.

<HUAWEI> system-view
[HUAWEI] dhcp enable 
[HUAWEI] dhcp anti-attack check duplicate option