arp gratuitous-arp send enable

Function

The arp gratuitous-arp send enable command enables gratuitous ARP packet sending.

The undo arp gratuitous-arp send enable command disables gratuitous ARP packet sending.

By default, gratuitous ARP packet sending is disabled.

Format

arp gratuitous-arp send enable

undo arp gratuitous-arp send enable

Parameters

None

Views

System view, VLANIF interface view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

If an attacker forges the gateway address to send ARP packets to other user hosts, ARP entries on the hosts record the incorrect gateway address. As a result, the gateway cannot receive data sent from the hosts. You can enable gratuitous ARP packet sending on the gateway. Then the gateway sends gratuitous ARP packets at intervals to update the ARP entries of authorized users so that the ARP entries contain the correct MAC address of the gateway.

By default, the device sends a gratuitous ARP packet every 60 seconds after this function is enabled. You can also set the interval using the arp gratuitous-arp send interval command.

Precautions

After you run the arp gratuitous-arp send enable command in the system view, gratuitous ARP packet sending is enabled on all VLANIF interfaces.

After you run the undo arp gratuitous-arp send enable command in the system view, gratuitous ARP packet sending is disabled on all VLANIF interfaces.

Example

# Enable gratuitous ARP packet sending on VLANIF 10.

<HUAWEI> system-view
[HUAWEI] interface vlanif 10
[HUAWEI-Vlanif10] arp gratuitous-arp send enable