Catalyst 3750-E and 3560-E Switch Cisco IOS ... - DNIP . NET

Chapter 2Catalyst 3750-E and 3560-E Switch Cisco IOS Commandsip arp inspection trustip arp inspection trustUse the ip arp inspection trust interface configuration command on the switch stack or on a standaloneswitch to configure an interface trust state that determines which incoming Address Resolution Protocol(ARP) packets are inspected. Use the no form of this command to return to the default setting.ip arp inspection trustno ip arp inspection trustThis command is available only if your switch is running the IP services feature set.Syntax DescriptionThis command has no arguments or keywords.DefaultsThe interface is untrusted.Command ModesInterface configurationCommand HistoryRelease12.2(35)SE2ModificationThis command was introduced.Usage GuidelinesThe switch does not check ARP packets that it receives on the trusted interface; it simply forwards thepackets.For untrusted interfaces, the switch intercepts all ARP requests and responses. It verifies that theintercepted packets have valid IP-to-MAC address bindings before updating the local cache and beforeforwarding the packet to the appropriate destination. The switch drops invalid packets and logs them inthe log buffer according to the logging configuration specified with the ip arp inspection vlan loggingglobal configuration command.ExamplesThis example shows how to configure a port to be trusted:Switch(config)# interface gigabitethernet1/0/1Switch(config-if)# ip arp inspection trustYou can verify your setting by entering the show ip arp inspection interfaces interface-id privilegedEXEC command.OL-9776-08Catalyst 3750-E and 3560-E Switch Command Reference2-221