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Configuration procedure, Configuring arp active acknowledgement – H3C Technologies H3C S6300 Series Switches User Manual

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3.

Set the lifetime for ARP attack entries.

4.

Exclude the MAC address of the server from this detection.

Configuration procedure

# Enable source MAC-based ARP attack detection, and specify the handling method as filter.

system-view

[Device] arp source-mac filter

# Set the threshold to 30.

[Device] arp source-mac threshold 30

# Set the lifetime for ARP attack entries to 60 seconds.

[Device] arp source-mac aging-time 60

# Exclude MAC address 0012-3f86-e94c from this detection.

[Device] arp source-mac exclude-mac 0012-3f86-e94c

Configuring ARP packet source MAC consistency
check

This feature enables a gateway to filter out ARP packets whose source MAC address in the Ethernet

header is different from the sender MAC address in the message body. This feature allows the gateway

to learn correct ARP entries.
To enable ARP packet source MAC address consistency check:

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

Enable ARP packet source MAC address

consistency check.

arp valid-check enable

By default, ARP packet source
MAC address consistency check
is disabled.

Configuring ARP active acknowledgement

Configure this feature on gateways to prevent user spoofing.
ARP active acknowledgement prevents a gateway from generating incorrect ARP entries.
In strict mode, a gateway performs more strict validity checks before creating an ARP entry:

Upon receiving an ARP request destined for the gateway, the gateway sends an ARP reply but does
not create an ARP entry.

Upon receiving an ARP reply, the gateway determines whether it has resolved the sender IP
address:

{

If yes, the gateway performs active acknowledgement. When the ARP reply is verified as valid,
the gateway creates an ARP entry.

{

If no, the gateway discards the packet.

To configure ARP active acknowledgement: