H3C S5120-EI Series, Руководство по эксплуатации

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1-5
Configuration Procedure
Follow these steps to enable ARP packet source MAC address consistency check:
To do… Use the command… Remarks
Enter system view
system-view
—
Enable ARP packet source MAC
address consistency check
arp anti-attack valid-check
enable
Required
Disabled by default.
Configuring ARP Active Acknowledgement
Introduction
Typically, the ARP active acknowledgement feature is configured on gateway devices to identify invalid
ARP packets.
With this feature enabled, the gateway, upon receiving an ARP packet with a different source MAC
address from that in the corresponding ARP entry, checks whether the ARP entry has been updated
within 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 Function
Follow these steps to configure ARP active acknowledgement:
To do… Use the command… Remarks
Enter system view
system-view
—
Enable the ARP active
acknowledgement function
arp anti-attack active-ack enable
Required
Disabled by default.
Configuring ARP Detection