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Cisco ME 3400 Ethernet Access Switch Software Configuration Guide
OL-9639-06
Chapter 20 Configuring Dynamic ARP Inspection Configuring Dynamic ARP Inspection
Beginning in privileged EXEC mode, follow these steps to configure an ARP ACL on Switch A. This
procedure is required in non-DHCP environments.
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 arp access-list acl-name Define an ARP ACL, and enter ARP access-list
configuration mode. By default, no ARP access lists
are defined.
Note At the end of the ARP access list, there is an
implicit deny ip any mac any command.
Step 3 permit ip host sender-ip mac host sender-mac [log]Permit ARP packets from the specified host (Host 2).
• For sender-ip, enter the IP address of Host 2.
• For sender-mac, enter the MAC address of
Host 2.
• (Optional) Specify log to log a packet in the log
buffer when it matches the access control entry
(ACE). Matches are logged if you also configure
the matchlog keyword in the ip arp inspection
vlan logging global configuration command. For
more information, see the “Configuring the Log
Buffer” section on page 20-12.
Step 4 exit Return to global configuration mode.
Step 5 ip arp inspection filter arp-acl-name vlan vlan-range
[static]Apply the ARP ACL to the VLAN. By default, no
defined ARP ACLs are applied to any VLAN.
• For arp-acl-name, specify the name of the ACL
created in Step 2.
• For vlan-range, specify the VLAN that the
switches and hosts are in. You can specify a
single VLAN identified by VLAN ID number, a
range of VLANs separated by a hyphen, or a
series of VLANs separated by a comma. The
range is 1 to 4094.
• (Optional) Specify static to treat implicit denies
in the ARP ACL as explicit denies and to drop
packets that do not match any previous clauses in
the ACL. DHCP bindings are not used.
If you do not specify this keyword, it means that
there is no explicit deny in the ACL that denies
the packet, and DHCP bindings determine
whether a packet is permitted or denied if the
packet does not match any clauses in the ACL.
ARP packets containing only IP-to-MAC address
bindings are compared against the ACL. Packets are
permitted only if the access list permits them.
Step 6 interface interface-id Specify the Switch A interface that is connected to
Switch B, and enter interface configuration mode.