Configuring The Log Buffer - Cisco Catalyst 4500 Series Configuration Manual

Configuring Dynamic ARP Inspection
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SwitchA# show ip arp inspection statistics vlan 100
Vlan
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100
Vlan
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100
Vlan
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100
SwitchA#

Configuring the Log Buffer

When the switch drops a packet, it places an entry in the log buffer and then generates system messages
on a rate-controlled basis. After the message is generated, the switch clears the entry from the log buffer.
Each log entry contains flow information, such as the receiving VLAN, the port number, the source and
destination IP addresses, and the source and destination MAC addresses.
A log-buffer entry can represent more than one packet. For example, if an interface receives many
packets on the same VLAN with the same ARP parameters, the switch combines the packets as one entry
in the log buffer and generates a single system message for the entry.
If the log buffer overflows, it means that a log event does not fit into the log buffer, and the display for
the show ip arp inspection log privileged EXEC command is affected. No other statistics are provided
for the entry.
Software Configuration Guide—Release IOS XE 3.3.0SG and IOS 15.1(1)SG
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Forwarded Dropped
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DHCP Permits ACL Permits
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Dest MAC Failures IP Validation Failures
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0
Chapter 49
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DHCP Drops
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Source MAC Failures
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Invalid Protocol Data
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0
Configuring Dynamic ARP Inspection
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ACL Drops
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