Cisco WS-C3560E-48PD-SF Command Reference - Page 181

Chapter 2 Catalyst 3560 Switch Cisco IOS Commands ip dhcp snooping limit rate ip dhcp snooping limit rate Use the ip dhcp snooping limit rate interface configuration command to configure the number of DHCP messages an interface can receive per second. Use the no form of this command to return to the default setting. ip dhcp snooping limit rate rate no ip dhcp snooping limit rate Syntax Description rate Number of DHCP messages an interface can receive per second. The range is 1 to 2048. Defaults DHCP snooping rate limiting is disabled. Command Modes Interface configuration Command History Release 12.1(19)EA1 12.2(18)SE Modification This command was introduced. The range was changed to 1 to 2048. Usage Guidelines Normally, the rate limit applies to untrusted interfaces. If you want to configure rate limiting for trusted interfaces, keep in mind that trusted interfaces might aggregate DHCP traffic on multiple VLANs (some of which might not be snooped) in the switch, and you will need to adjust the interface rate limits to a higher value. If the rate limit is exceeded, the interface is error-disabled. If you enabled error recovery by entering the errdisable recovery dhcp-rate-limit global configuration command, the interface retries the operation again when all the causes have timed out. If the error-recovery mechanism is not enabled, the interface stays in the error-disabled state until you enter the shutdown and no shutdown interface configuration commands. Examples This example shows how to set a message rate limit of 150 messages per second on an interface: Switch(config-if)# ip dhcp snooping limit rate 150 You can verify your settings by entering the show ip dhcp snooping privileged EXEC command. 78-16405-05 Catalyst 3560 Switch Command Reference 2-149