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INTERFACE VLAN mode
arp inspection
Examples of Viewing the ARP Information
To view entries in the ARP database, use the show arp inspection database command.
DellEMC#show arp inspection database
Protocol Address Age(min) Hardware Address Interface VLAN CPU
---------------------------------------------------------------------
Internet 10.1.1.251 - 00:00:4d:57:f2:50 Te 1/2/1 Vl 10 CP
Internet 10.1.1.252 - 00:00:4d:57:e6:f6 Te 1/1/1 Vl 10 CP
Internet 10.1.1.253 - 00:00:4d:57:f8:e8 Te 1/3/1 Vl 10 CP
Internet 10.1.1.254 - 00:00:4d:69:e8:f2 Te 1/5/1 Vl 10 CP
DellEMC#
To see how many valid and invalid ARP packets have been processed, use the show arp inspection statistics command.
DellEMC#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
DellEMC#
Bypassing the ARP Inspection
You can congure a port to skip ARP inspection by dening 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.
To bypass the ARP inspection, use the following command.
• Specify an interface as trusted so that ARPs are not validated against the binding table.
INTERFACE mode
arp inspection-trust
Dynamic ARP inspection is supported on Layer 2 and Layer 3.
Source Address Validation
Using the DHCP binding table, Dell EMC Networking OS can perform three types of source address validation (SAV).
Table 26. Three Types of Source Address Validation
Source Address Validation Description
IP Source Address Validation Prevents IP spoong by forwarding only IP packets that have been
validated against the DHCP binding table.
DHCP MAC Source Address Validation Veries a DHCP packet’s source hardware address matches the
client hardware address eld (CHADDR) in the payload.
IP+MAC Source Address Validation Veries that the IP source address and MAC source address are a
legitimate pair.
Dynamic Host Conguration Protocol (DHCP) 313