Purpose
Command or Action
Verify your settings.
show ip arp inspection interfaces
show errdisable recovery
Step 7
(Optional) Save your entries in the configuration file.
copy running-config startup-config
Step 8
How to Perform Validation Checks
Dynamic ARP inspection intercepts, logs, and discards ARP packets with invalid IP-to-MAC address bindings.
You can configure the switch to perform additional checks on the destination MAC address, the sender and
target IP addresses, and the source MAC address. Beginning in privileged EXEC mode, follow these steps to
perform specific checks on incoming ARP packets.
This procedure is optional.
To disable checking, use the
no ip arp inspection validate [src-mac] [dst-mac] [ip]
global configuration
command. To display statistics for forwarded, dropped, and MAC and IP validation failure packets, use the
show ip arp inspection statistics
privileged EXEC command.
SUMMARY STEPS
1.
configure terminal
2.
ip arp inspection validate {[src-mac] [dst-mac] [ip]}
3.
exit
4.
show ip arp inspection vlan vlan-range
5.
copy running-config startup-config
DETAILED STEPS
Purpose
Command or Action
Enter global configuration mode.
configure terminal
Step 1
Perform a specific check on incoming ARP packets. By default, no checks are performed.
ip arp inspection validate
{[src-mac] [dst-mac] [ip]}
Step 2
The keywords have these meanings:
•
For
src-mac
, check the source MAC address in the Ethernet header against the
sender MAC address in the ARP body. This check is performed on both ARP
requests and responses. When enabled, packets with different MAC addresses are
classified as invalid and are dropped.
•
For
dst-mac
, check the destination MAC address in the Ethernet header against
the target MAC address in ARP body. This check is performed for ARP responses.
When enabled, packets with different MAC addresses are classified as invalid and
are dropped.
Catalyst 2960-XR Switch Security Configuration Guide, Cisco IOS Release 15.0(2)EX1
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Configuring Dynamic ARP Inspection
How to Perform Validation Checks