H3C Technologies H3C S12500-X Series Switches - Manual (Page 238)

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Static IP source guard binding entries are created by using the ip source binding command. For more
information, see "
932H
Configuring IP source guard ."
DHCP snooping entries are automatically generated by DHCP snooping. For more information, see
Layer 3—IP Services Configuration Guide.
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Configuration guidelines
When you configure user validity check, follow these guidelines:
• Make sure at least one among static IP source guard binding entries and DHCP snooping entries is
available 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.
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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.
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.
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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