1-5Configuration ProcedureFollow these steps to enable ARP packet source MAC address consistency check:To do… Use the command… RemarksEnter system view system-view —Enable ARP packet source MACaddress consistency checkarp anti-attack valid-checkenableRequiredDisabled by default.Configuring ARP Active AcknowledgementIntroductionTypically, the ARP active acknowledgement feature is configured on gateway devices to identify invalidARP packets.With this feature enabled, the gateway, upon receiving an ARP packet with a different source MACaddress from that in the corresponding ARP entry, checks whether the ARP entry has been updatedwithin the last minute:z If yes, the gateway does not update the ARP entry;z If not, the gateway unicasts an ARP request to the source MAC address of the ARP entry.Then,z If an ARP reply is received within five seconds, the ARP packet is ignored;z If not, the gateway unicasts an ARP request to the MAC address of the ARP packet.Then,z If an ARP reply is received within five seconds, the gateway updates the ARP entry;z If not, the ARP entry is not updated.Configuring the ARP Active Acknowledgement FunctionFollow these steps to configure ARP active acknowledgement:To do… Use the command… RemarksEnter system view system-view —Enable the ARP activeacknowledgement function arp anti-attack active-ack enable RequiredDisabled by default.Configuring ARP Detection
