Cisco WS-C3560E-48PD-SF Command Reference - Page 163

Chapter 2 Catalyst 3560 Switch Cisco IOS Commands ip arp inspection log-buffer ip arp inspection log-buffer Use the ip arp inspection log-buffer global configuration command to configure the dynamic Address Resolution Protocol (ARP) inspection logging buffer. Use the no form of this command to return to the default settings. ip arp inspection log-buffer {entries number | logs number interval seconds} no ip arp inspection log-buffer {entries | logs} Syntax Description entries number logs number interval seconds Number of entries to be logged in the buffer. The range is 0 to 1024. Number of entries needed in the specified interval to generate system messages. For logs number, the range is 0 to 1024. A 0 value means that the entry is placed in the log buffer, but a system message is not generated. For interval seconds, the range is 0 to 86400 seconds (1 day). A 0 value means that a system message is immediately generated (and the log buffer is always empty). Defaults When dynamic ARP inspection is enabled, denied or dropped ARP packets are logged. The number of log entries is 32. The number of system messages is limited to 5 per second. The logging-rate interval is 1 second. Command Modes Global configuration Command History Release 12.2(20)SE Modification This command was introduced. Usage Guidelines A value of 0 is not allowed for both the logs and the interval keywords. The logs and interval settings interact. If the logs number X is greater than interval seconds Y, X divided by Y (X/Y) system messages are sent every second. Otherwise, one system message is sent every Y divided by X (Y/X) seconds. For example, if the logs number is 20 and the interval seconds is 4, the switch generates system messages for five entries every second while there are entries in the log buffer. 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 system message as a single entry. If the log buffer overflows, it means that a log event does not fit into the log buffer, and the output display for the show ip arp inspection log privileged EXEC command is affected. A -- in the output display appears in place of all data except the packet count and the time. No other statistics are provided for the entry. If you see this entry in the display, increase the number of entries in the log buffer, or increase the logging rate. 78-16405-05 Catalyst 3560 Switch Command Reference 2-131