ProSafe XSM7224S Managed Stackable Switch CLI Manual, Software Version 9.0
Switching Commands 3-134
v1.0, November 2010
00:00:00:00:00:08 1.2.3.4 dhcp-snooping 2 1/0/1
00:00:00:00:00:09 1.2.3.4 dhcp-snooping 3 1/0/1
00:00:00:00:00:0A 1.2.3.4 dhcp-snooping 4 1/0/1
Dynamic ARP Inspection Commands
Dynamic ARP Inspection (DAI) is a security feature that rejects invalid and malicious ARP
packets. DAI prevents a class of man-in-the-middle attacks, where an unfriendly station intercepts
traffic for other stations by poisoning the ARP caches of its unsuspecting neighbors. The miscreant
sends ARP requests or responses mapping another station’s IP address to its own MAC address.
DAI relies on DHCP snooping. DHCP snooping listens to DHCP message exchanges and builds a
binding database of valid {MAC address, IP address, VLAN, and interface} tuples.
When DAI is enabled, the switch drops ARP packets whose sender MAC address and sender IP
address do not match an entry in the DHCP snooping bindings database. You can optionally
configure additional ARP packet validation.
ip arp inspection vlan
Use this command to enable Dynamic ARP Inspection on a list of comma-separated VLAN
ranges.
no ip arp inspection vlan
Use this command to disable Dynamic ARP Inspection on a list of comma-separated VLAN
ranges.
Default disabled
Format ip arp inspection vlan vlan-list
Mode Global Config
Format no ip arp inspection vlan vlan-list
Mode Global Config