431
# Configure ARP restricted forwarding.
[RouterB] vlan 10
[RouterB-vlan10] arp restricted-forwarding enable
[RouterB-vlan10] quit
Then, Router B forwards ARP broadcast requests from Host A to Router A through the trusted port
GigabitEthernet1/0/3, and thus Host B cannot receive such packets. Port isolation works normally.
Configuring ARP automatic scanning and fixed ARP
ARP automatic scanning is usually used together with the fixed ARP feature.
With ARP automatic scanning enabled on an interface, the device automatically scans neighbors on the
interface, sends ARP requests to the neighbors, obtains their MAC addresses, and creates dynamic ARP
entries.
Fixed ARP allows the device to change the existing dynamic ARP entries (including those generated
through ARP automatic scanning) into static ARP entries. The fixed ARP feature effectively prevents ARP
entries from being modified by attackers.
NOTE:
HP recommends that you use ARP automatic scanning and fixed ARP in a small-scale network such as
a cybercafe.
Configuration procedure
To do…
Command…
Remarks
1.
Enter system view.
system-view
—
2.
Enter interface view.
interface
interface-type interface-number
—
3.
Enable ARP automatic scanning.
arp scan
[
start-ip-address
to
end-ip-address
]
Required
4.
Return to system view.
quit
—
5.
Enable fixed ARP.
arp fixup
Required