Configuring Dhcp Snooping Rate Limiting On Layer 2 Lan Interfaces; Configuring The Dhcp Snooping Database Agent - Cisco 7604 Configuration Manual

Configuring DHCP Snooping

Configuring DHCP Snooping Rate Limiting on Layer 2 LAN Interfaces

To configure DHCP snooping rate limiting on a Layer 2 LAN interface, perform this task:
Command
Step 1
Router(config)# interface { type
port-channel number }
Step 2
Router(config-if)# ip dhcp snooping limit rate
rate
Step 3
Router(config-if)# no ip dhcp snooping limit rate
Step 4
Router(config-if)# do show ip dhcp snooping |
begin pps
1. type = ethernet, fastethernet, gigabitethernet, or tengigabitethernet
When configuring DHCP snooping rate limiting on a Layer 2 LAN interface, note the following
information:
•
•
•
This example shows how to configure DHCP packet rate limiting to 100 pps on Fast Ethernet port 5/12:
Router# configure terminal
Router(config)# interface FastEthernet 5/12
Router(config-if)# ip dhcp snooping limit rate 100
Router(config-if)# do show ip dhcp snooping | begin pps
Interface
------------------------
FastEthernet5/12
Router#

Configuring the DHCP Snooping Database Agent

To configure the DHCP snooping database agent, perform one or more of the following tasks:
Command
Router(config)# ip dhcp snooping database { _url |
write-delay seconds | timeout seconds }
Router(config)# no ip dhcp snooping database
[write-delay | timeout]
Router# show ip dhcp snooping database [detail]
Router# clear ip dhcp snooping database statistics
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
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1
slot/port |
We recommend an untrusted rate limit of not more than 100 packets per second (pps).
If you configure rate limiting for trusted interfaces, you might need to increase the rate limit on trunk
ports carrying more than one VLAN on which DHCP snooping is enabled.
DHCP snooping puts ports where the rate limit is exceeded into the error-disabled state.
Purpose
Selects the interface to configure.
Select only LAN ports configured with the
Note
switchport command or Layer 2 port-channel
interfaces.
Configures DHCP packet rate limiting.
Disables DHCP packet rate limiting.
Verifies the configuration.
Trusted Rate limit (pps)
------- ----------------
no 100
Purpose
(Required) Configures a URL for the database agent (or file)
and the related timeout values.
Clears the configuration.
(Optional) Displays the current operating state of the
database agent and statistics associated with the transfers.
(Optional) Clears the statistics associated with the database
agent.
Chapter 37 Configuring DHCP Snooping
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