R3303-HP HSR6800 Routers Security Configuration Guide

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[RouterB-GigabitEthernet3/0/2] ip source binding ip-address 10.1.1.6 mac-address
0001-0203-0607 vlan 10
[RouterB-GigabitEthernet3/0/2] ip verify source ip-address mac-address
[RouterB-GigabitEthernet3/0/2] quit
# Enable ARP packet validity check by checking the MAC addresses and IP addresses of ARP
packets.
[RouterB] arp detection validate dst-mac ip src-mac
# Configure port isolation.
[RouterB] interface gigabitethernet 3/0/1
[RouterB-GigabitEthernet3/0/1] port link-mode bridge
[RouterB-GigabitEthernet3/0/1] port-isolate enable
[RouterB-GigabitEthernet3/0/1] quit
[RouterB] interface gigabitethernet 3/0/2
[RouterB-GigabitEthernet3/0/2] port-isolate enable
[RouterB-GigabitEthernet3/0/2] quit
After the preceding configurations are complete, ARP packets received on interfaces
GigabitEthernet 3/0/1 and GigabitEthernet 3/0/2 have their MAC and IP addresses checked
first, and then are checked against the static IP source guard binding entries and finally DHCP
snooping entries. However, ARP broadcast requests sent from Host A can pass the check on Router
B. Port isolation fails.
# Enable ARP restricted forwarding.
[RouterB] vlan 10
[RouterB-vlan10] arp restricted-forwarding enable
[RouterB-vlan10] quit
After the configuration, Router B forwards ARP broadcast requests from Host A to Router A through
the trusted port GigabitEthernet 3/0/3, and thus Host B cannot receive such packets. Port isolation
works correctly.
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.
Use both ARP automatic scanning and fixed ARP in small-scale networks such as a cybercafe.
Configuration guidelines
When you configure ARP automatic scanning and fixed ARP, follow these guidelines:
• IP addresses existing in ARP entries are not scanned.
• ARP automatic scanning might take some time. To stop an ongoing scan, press Ctrl + C. Dynamic
ARP entries are created based on ARP replies received before the scan is terminated.