Cisco Systems 3130 User Manual

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Cisco Catalyst Blade Switch 3130 for Dell Software Configuration Guide
OL-13270-01
Chapter 21      Configuring DHCP Features and IP Source Guard
Configuring DHCP Features
Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# ip dhcp snooping limit rate 100
Enabling DHCP Snooping on Private VLANs
You can enable DHCP snooping on private VLANs. If DHCP snooping is enabled, the configuration is 
propagated to both a primary VLAN and its associated secondary VLANs. If DHCP snooping is enabled 
on the primary VLAN, it is also configured on the secondary VLANs. 
If DHCP snooping is already configured on the primary VLAN and you configure DHCP snooping with 
different settings on a secondary VLAN, the configuration for the secondary VLAN does not take effect. 
You must configure DHCP snooping on the primary VLAN. If DHCP snooping is not configured on the 
primary VLAN, this message appears when you are configuring DHCP snooping on the secondary 
VLAN, such as VLAN 200:
2w5d:%DHCP_SNOOPING-4-DHCP_SNOOPING_PVLAN_WARNING:DHCP Snooping configuration may not take 
effect on secondary vlan 200. DHCP Snooping configuration on secondary vlan is derived 
from its primary vlan.
The show ip dhcp snooping privileged EXEC command output shows all VLANs, including primary 
and secondary private VLANs, on which DHCP snooping is enabled. 
Enabling the Cisco IOS DHCP Server Database
For procedures to enable and configure the Cisco IOS DHCP server database, see the “DHCP 
Configuration Task List” section in the “Configuring DHCP” chapter of the Cisco IOS IP Configuration 
Guide, Release 12.2
.
Enabling the DHCP Snooping Binding Database Agent
Beginning in privileged EXEC mode, follow these steps to enable and configure the DHCP snooping 
binding database agent on the switch:
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
ip dhcp snooping database 
{flash[number]:/filename | 
ftp://user:password@host/filename | 
http://[[username:password]@]{hostna
me | host-ip
}[/directory]
/image-name.tar 
rcp://user@host/filename}| 
tftp://host/filename
Specify the URL for the database agent or the binding file by using one 
of these forms:
flash[number]:/filename
(Optional) Use the number parameter to specify the stack member 
number of the stack master. The range for number is 1 to 9.
ftp://user:password@host/filename 
http://[[username:password]@]{hostname | host-ip}[/directory]
/image-name.tar
rcp://user@host/filename
tftp://host/filename