You can define the trusted and untrusted interfaces under Dynamic ARP Inspection (DAI).
device# configure terminal
device(config)# interface ethernet 2/3
device(conf-if-eth-2/3)# ip arp inspection trust
device(conf-if-eth-2/3)# no ip arp inspection trust
The following example defines a port-channel interface as trusted.
device# configure terminal device(config)# interface port-channel 200 device(config-Port-channel-200)# ip arp inspection trust
The following example defines a port-channel interface as untrusted.
device# configure terminal device(config)# interface port-channel 200 device(config-Port-channel-200)# no ip arp inspection trust