arp status-detect

Function

The arp status-detect command enables association between ARP and interface status.

The undo arp status-detect command disables association between ARP and interface status.

By default, association between ARP and interface status is disabled, an interface sends ARP probe messages in strict mode, ARP probe messages are sent at an interval of 1000 milliseconds, an interface sends ARP probe messages for three consecutive times.

Format

arp status-detect ip-address

arp status-detect { interval detect-interval | times detect-times | mode loose }

undo arp status-detect [ ip-address ]

undo arp status-detect { interval [ detect-interval ] | times [ detect-times ] | mode [ loose ] }

Parameters

Parameter	Description	Value
ip-address	Specifies the destination IP address of ARP probe messages sent by an interface. The destination IP address of ARP probe messages must be on the same network segment as the IP address of the local interface. The probed device does not need to be configured.	The value is in dotted decimal notation.
interval detect-interval	Specifies the interval at which ARP probe messages are sent.	The value is an integer ranging from 200 to 10000, in milliseconds.
times detect-times	Specifies the maximum number of times an interface can consecutively send ARP probe messages. If no ARP reply messages are received within the specified period, the protocol status of the interface is set to Down.	The value is an integer ranging from 1 to 10.
mode loose	Indicates that an interface sends ARP probe messages in loose mode. In strict mode, an interface sends ARP probe messages when the physical status is Up. The protocol status of the local interface remains unchanged only when the local interface receives an ARP reply packet from the peer interface and the source IP address of the ARP reply packet is the same as the destination IP address of the ARP probe packet. If no ARP reply packet is received from the peer interface within the allowable attempts, the protocol status of the local interface is set to Down. In loose mode, an interface sends ARP probe messages only when both the physical status and protocol status are Up. The protocol status of the local interface remains unchanged only when the local interface receives an ARP packet from the peer interface and the source IP address of the ARP packet is the same as the destination IP address of the ARP probe packet. If no ARP packet is received from the peer interface within the allowable attempts, the protocol status of the local interface is set to Down.	-

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, FlexE sub-interface view, FlexE interface view, GE optical interface view, GE sub-interface view, GE interface view, GE electrical interface view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
arp	write

Usage Guidelines

Usage Scenario

To minimize the impact of device faults on services and improve network availability, a network device must be able to quickly detect communication faults of devices that are not directly connected. Then, measures can be taken to quickly rectify the faults to ensure the normal running of services.

Association between ARP and interface status allows the local interface to send ARP probe packets to the peer interface and checks whether the peer interface can properly forward packets based on whether a reply packet is received. This triggers fast route convergence.

Precautions

Before enabling association between ARP and interface status, run the ip address ip-address { mask | mask-length } [ sub ] command to configure the IP address of the local interface.

In the sub-interface view, this command applies only to Layer 3 sub-interfaces.

Set the interval at which ARP probe messages are sent to a large value to prevent interface flapping upon operations such as primary/secondary switching.

Example

# Enable an interface to send ARP probe packets with the local IP address of 10.1.1.1/24 and peer IP address of 10.1.1.2/24, configure an interface to send ARP probe messages in loose mode.

<HUAWEI> system-view
[~HUAWEI] interface GigabitEthernet 0/1/1
[*HUAWEI-GigabitEthernet0/1/1] ip address 10.1.1.1 24
[*HUAWEI-GigabitEthernet0/1/1] arp status-detect 10.1.1.2
[*HUAWEI-GigabitEthernet0/1/1] arp status-detect mode loose