Cisco Catalyst Blade Switch 3020 for HP Software Configuration Guide, Rel. 12.2(25)SEF1

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Cisco Catalyst Blade Switch 3020 for HP Software Configuration Guide
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Chapter 17 Configuring DHCP Features
Displaying DHCP Snooping Information
To disable DHCP snooping, use the no ip dhcp snooping global configuration command. To disable
DHCP snooping on a VLAN or range of VLANs, use the no ip dhcp snooping vlan vlan-range global
configuration command. To disable the insertion and removal of the option-82 field, use the no ip dhcp
snooping information option global configuration command. To configure an aggregation switch to
drop incoming DHCP snooping packets with option-82 information from an edge switch, use the no ip
dhcp snooping information option allow-untrusted global configuration command.
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 gigabitethernet0/1
Switch(config-if)# ip dhcp snooping limit rate 100
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.
Displaying DHCP Snooping Information
To display the DHCP snooping information, use one or more of the privileged EXEC commands in
Table 17-2:
Note If DHCP snooping is enabled and an interface changes to the down state, the switch does not delete the
statically configured bindings.
Table 17-2 Commands for Displaying DHCP Information
Command Purpose
show ip dhcp snooping Displays the DHCP snooping configuration for a switch
show ip dhcp snooping binding Displays only the dynamically configured bindings in the DHCP snooping binding
database, also referred to as a binding table.