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Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
OL-12247-04
Chapter 22 Configuring DHCP Features and IP Source Guard
Configuring DHCP Features
This example shows how to enable DHCP snooping globally and on VLAN 10 and to configure a rate
limit of 100 packets per second on a port:
Switch(config)#
ip dhcp snooping
Switch(config)#
ip dhcp snooping vlan 10
Switch(config)#
ip dhcp snooping information option
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
.