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Configuration guidelines, Configuration procedure, Configuring arp packet validity check – H3C Technologies H3C S6300 Series Switches User Manual

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Static IP source guard binding entries are created by using the ip source binding command. For more

information, see "

Configuring IP source guard

."

DHCP snooping entries are automatically generated by DHCP snooping. For more information, see

Layer 3—IP Services Configuration Guide.

Configuration guidelines

When you configure user validity check, follow these guidelines:

Make sure at least one of static IP source guard binding and DHCP snooping is configured for user
validity check. Otherwise, ARP packets received from ARP untrusted ports are discarded.

You must specify a VLAN for an IP source guard binding entry. Otherwise, no ARP packets can

match the IP source guard binding entry.

Configuration procedure

To configure user validity check:

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

Enter VLAN view.

vlan vlan-id N/A

3.

Enable ARP detection.

arp detection enable

By default, ARP detection is disabled.

4.

Return to system view.

quit

N/A

5.

Enter Layer 2 Ethernet interface

view or Layer 2 aggregate
interface view.

interface interface-type
interface-number

N/A

6.

(Optional.) Configure the

interface as a trusted interface
excluded from ARP detection.

arp detection trust

By default, an interface is untrusted.

Configuring ARP packet validity check

Enable validity check for ARP packets received on untrusted ports and specify the following objects to be
checked:

src-mac—Checks whether the sender MAC address in the message body is identical to the source
MAC address in the Ethernet header. If they are identical, the packet is forwarded. Otherwise, the

packet is discarded.

dst-mac—Checks the target MAC address of ARP replies. If the target MAC address is all-zero,
all-one, or inconsistent with the destination MAC address in the Ethernet header, the packet is

considered invalid and discarded.

ip—Checks the sender and target IP addresses of ARP replies, and the sender IP address of ARP
requests. All-one, or multicast IP addresses are considered invalid and the corresponding packets

are discarded.

To configure ARP packet validity check:

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

Enter VLAN view.

vlan vlan-id N/A