DELL S50V User Manual

Page of 1262
Dynamic Host Configuration Protocol | 327
View the number of entries in the ARP database with the 
show arp inspection database
 command.
Figure 13-8.  Command example: 
show arp inspection database
Use 
show arp inspection statistics
 command to see how many valid and invalid ARP packets have been 
processed.
Figure 13-9.  Command example: 
show arp inspection database
Bypass the ARP Inspection
You can configure a port to skip ARP inspection by defining the interface as trusted, which is useful in 
multi-switch environments. ARPs received on trusted ports bypass validation against the binding table. All 
ports are untrusted by default.
Source Address Validation
Using the DHCP binding table, FTOS can perform three types of source address validation (SAV):
have been validated against the DHCP binding table.
Task
Command Syntax
Command Mode
Specify an interface as trusted so that ARPs are not 
validated against the binding table.
arp inspection-trust
INTERFACE
FTOS Behavior: Introduced in FTOS version 8.2.1.0, Dynamic ARP Inspection (DAI) was available for 
Layer 3 only. FTOS version 8.2.1.1 extends DAI to Layer 2.
FTOS#
show arp inspection database
 
Protocol    Address         Age(min)  Hardware Address    Interface   VLAN  CPU
----------------------------------------------------------------------------
Internet    10.1.1.251           -   00:00:4d:57:f2:50    Gi 0/2     Vl 10  CP
Internet    10.1.1.252           -   00:00:4d:57:e6:f6    Gi 0/1     Vl 10  CP
Internet    10.1.1.253           -   00:00:4d:57:f8:e8    Gi 0/3     Vl 10  CP
Internet    10.1.1.254           -   00:00:4d:69:e8:f2    Te 0/50     Vl 10  CP
FTOS#
FTOS#
show arp inspection statistics
 
Dynamic ARP Inspection (DAI) Statistics
---------------------------------------
Valid ARP Requests                        : 0
Valid ARP Replies                         : 1000
Invalid ARP Requests                      : 1000
Invalid ARP Replies                       : 0
FTOS#