Configuring Arp Detection Based On Specified Objects - H3C LS-3100-52P-OVS-H3 Operation Manual

To do...
Enter system view
Enter VLAN view
Enable ARP detection for
the VLAN
Return to system view
Enter Ethernet interface
view
Configure the port as a
trusted port
Return to system view
Specify an ARP attack
detection mode
Configure a static
IP-to-MAC binding for ARP
detection
During the DHCP assignment process, when the client receives the DHCP-ACK message from the
DHCP server, it broadcasts a gratuitous ARP packet to detect address conflicts. If no response is
received in a pre-defined time period, the client uses the assigned IP address. If the client is enabled
with ARP detection based on 802.1X security entries, the IP address is not uploaded to the 802.1X
device before the client uses the IP address. As a result, the gratuitous ARP packet is considered to be
an attack packet and is discarded, and thus cannot detect conflicts. After the client uploads its IP
address to the 802.1X device, subsequent ARP packets sent by the client are considered to be valid
and are allowed to travel through.

Configuring ARP Detection Based on Specified Objects

You can also specify objects in ARP packets to be detected. The objects involve:
src-mac: Checks whether the sender MAC address of an ARP packet is identical to the source
MAC address in the Ethernet header. If they are identical, the packet is forwarded; otherwise, the
packet is discarded.
Use the command...
system-view
vlan vlan-id
arp detection enable
quit
interface interface-type
interface-number
arp detection trust
quit
arp detection mode
{ dhcp-snooping | dot1x |
static-bind } *
arp detection static-bind
ip-address mac-address
3-7
Remarks
—
—
Required
Disabled by default. That is, the ARP
packets received on all the ports in the
VLAN will not be checked.
—
—
Optional
The port is an untrusted port by
default.
—
Required
No ARP attack detection mode is
specified by default; that is, ARP
detection based on DHCP snooping
entries/802.1x security entries/static
IP-to-MAC bindings is not enabled by
default.
Optional
Not configured by default.
If the ARP attack detection mode is
static-bind, you need to configure
static IP-to-MAC bindings for ARP
detection.