Table of Contents
Advertisement
• When ARP Inspection is enabled globally and enabled on selected VLANs, all
ARP request and reply packets on those VLANs are redirected to the CPU
and their switching is handled by the ARP Inspection engine.
• When ARP Inspection is disabled globally, it becomes inactive for all VLANs,
including those where ARP Inspection is enabled.
• When ARP Inspection is disabled, all ARP request and reply packets bypass
the ARP Inspection engine and their manner of switching matches that of all
other packets.
• Disabling and then re-enabling global ARP Inspection will not affect the ARP
Inspection configuration for any VLANs.
• When ARP Inspection is disabled globally, it is still possible to configure ARP
Inspection for individual VLANs. These configuration changes will only
become active after ARP Inspection is globally enabled again.
Example
Console(config)#ip arp inspection vlan 1,2
Console(config)#
This command specifies an ARP ACL to apply to one or more VLANs. Use the no
form to remove an ACL binding.
Syntax
ip arp inspection filter arp-acl-name vlan {vlan-id | vlan-range} [static]
• arp-acl-name - Name of an ARP ACL. (Maximum length: 16 characters)
• vlan-id - VLAN ID. (Range: 1-4094)
• vlan-range - A consecutive range of VLANs indicated by the use a hyphen,
or a random group of VLANs with each entry separated by a comma.
• static - ARP packets are only validated against the specified ACL, address
bindings in the DHCP snooping database is not checked.
Default Setting
ARP ACLs are not bound to any VLAN
Static mode is not enabled
Command Mode
Global Configuration
Command Usage
• ARP ACLs are configured with the commands described on page 4-212.
• If static mode is enabled, the switch compares ARP packets to the specified
ARP ACLs. Packets matching an IP-to-MAC address binding in a permit or
deny rule are processed accordingly. Packets not matching any of the ACL
rules are dropped. Address bindings in the DHCP snooping database are not
checked.
General Security Measures
4
4-193
Advertisement
Table of Contents
