ipv6 nd dad attempts

Function

The ipv6 nd dad attempts command sets the number of NS messages that are sent when Duplicate Address Detection (DAD) is performed.

The undo ipv6 nd dad attempts command restores the default setting.

By default, one NS message is sent when DAD is performed.

Format
Parameters
Views
Default Level
Task Name and Operations
Usage Guidelines
Example

Format

ipv6 nd dad attempts value

undo ipv6 nd dad attempts

Parameters

Parameter	Description	Value
value	Specifies the number of NS messages that are sent when DAD is performed.	It is an integer ranging from 0 to 600.

Parameter

Description

Value

value

Specifies the number of NS messages that are sent when DAD is performed.

It is an integer ranging from 0 to 600.

Views

100ge sub-interface view, 100GE interface view, 10GE sub-interface view, 10GE interface view, 200GE sub-interface view, 25GE sub-interface view, 25GE interface view, 400GE sub-interface view, 400GE interface view, 40GE sub-interface view, 40GE interface view, 50GE sub-interface view, 50GE interface view, Eth-Trunk sub-interface view, Eth-Trunk interface view, FlexE interface view, GE optical interface view, GE sub-interface view, GE interface view, GE electrical interface view, Global VE sub-interface view, PW-VE sub-interface view, PW-VE interface view, VBDIF interface view, VE sub-interface view, VLANIF interface view, Management interface view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
nd	write

Usage Guidelines

Usage Scenario

When you configure IPv6 addresses (including global unicast IPv6 addresses and link-local IPv6 addresses) for interfaces, the DAD function is required. DAD verifies the uniqueness of new unicast IPv6 addresses before the addresses are assigned to interfaces on the local link. It ensures that the IPv6 address to be allocated to an interface is not used by any other interfaces connected with this interface and thus avoids address conflicts.

Prerequisites

IPv6 has been enabled on the involved interface using the ipv6 enable command.

Configuration Impact

If the number of NS messages that are sent when DAD is performed is set to 0, it indicates that DAD is prohibited.

Precautions

When the physical link on an interface fails, DAD cannot be implemented on the interface.

When traffic is heavy, setting the value to a larger value is recommended to increase the number of NS messages that can be sent.

Example

# Disable the DAD function.

<HUAWEI> system-view
[~HUAWEI] interface GigabitEthernet 0/1/1
[~HUAWEI-GigabitEthernet0/1/1] ipv6 enable
[*HUAWEI-GigabitEthernet0/1/1] ipv6 nd dad attempts 0

# Set the number of NS messages that are sent when DAD is performed to 20.

<HUAWEI> system-view
[~HUAWEI] interface GigabitEthernet 0/1/1
[~HUAWEI-GigabitEthernet0/1/1] ipv6 enable
[*HUAWEI-GigabitEthernet0/1/1] ipv6 nd dad attempts 20