The arp anti-attack gratuitous-arp drop command enables gratuitous ARP packet discarding.
The undo arp anti-attack gratuitous-arp drop command disables gratuitous ARP packet discarding.
By default, gratuitous ARP packet discarding is disabled.
Usage Scenario
When a device is connected to a network for the first time, the device broadcasts gratuitous ARP packets to announce its existence and checks whether its IP address conflicts with any other device IP address in the broadcast domain. Any device can send gratuitous ARP packets and receive gratuitous ARP packets without authentication. As a result, a large number of gratuitous ARP packets can be generated, causing devices to be busy processing these packets. This process overloads the CPU and affects the processing of other services. To resolve this problem, you can enable gratuitous ARP packet discarding. After gratuitous ARP packet discarding is enabled, the device discards all received gratuitous ARP packets to prevent excessive CPU consumption.
Configuration Impact
After the arp anti-attack gratuitous-arp drop command is run, the device discards all received gratuitous ARP packets. The device is unaware of new access devices.
Precautions
Gratuitous ARP packet discarding can be enabled in the system view or in the interface view.