Cisco 4500M Software Manual page 480

Configuring Dynamic ARP Inspection
Interface
---------------
Gi1/1
Gi1/2
Gi3/1
Gi3/2
Fa3/3
Fa3/4
Fa3/5
Fa3/6
Fa3/7
<output truncated>
S2#
Verify the list of DHCP snooping bindings:
Step 4
S2# show ip dhcp snooping binding
MacAddress
------------------
00:01:00:01:00:01
S2#
Check the statistics before and after Dynamic ARP processes any packets:
Step 5
S2# show ip arp inspection statistics vlan 1
Vlan
----
1
Vlan
----
1
Vlan
----
1
S2#
If H2 then sends out an ARP request with the IP address 1.1.1.1 and the MAC address 0001.0001.0001,
the packet is forwarded and the statistics are updated appropriately:
S2# show ip arp inspection statistics vlan 1
Vlan
----
1
Vlan
----
1
Vlan
----
1
S2#
Conversely, if H2 attempts to send an ARP request with the IP address 1.1.1.2, the request is dropped
and an error message is logged:
00:18:08: %SW_DAI-4-DHCP_SNOOPING_DENY: 1 Invalid ARPs (Req) on Fa3/4, vlan
1.([0001.0001.0001/1.1.1.2/0000.0000.0000/0.0.0.0/01:53:21 UTC Fri May 23 2003])
S2#
Software Configuration Guide—Release 12.2(25)EW
34-8
Trust State
-----------
Untrusted
Untrusted
Untrusted
Untrusted
Trusted
Untrusted
Untrusted
Untrusted
Untrusted
IpAddress
---------------
1.1.1.1
Forwarded Dropped
--------- -------
0
DHCP Permits ACL Permits
------------ -----------
0
Dest MAC Failures IP Validation Failures
----------------- ----------------------
0
Forwarded Dropped
--------- -------
1
DHCP Permits ACL Permits
------------ -----------
1
Dest MAC Failures IP Validation Failures
----------------- ----------------------
0
Chapter 34 Understanding and Configuring Dynamic ARP Inspection
Rate (pps)
----------
15
15
15
15
None
15
15
15
15
Lease(sec) Type
---------- -------------
4995 dhcp-snooping
DHCP Drops ACL Drops
---------- ----------
0 0
Source MAC Failures
-------------------
0 0
0
DHCP Drops ACL Drops
---------- ----------
0 0
Source MAC Failures
-------------------
0 0
0
VLAN Interface
---- --------------------
1 FastEthernet3/4
0
0
OL-6696-01