Cisco Catalyst 4500 Series Command Reference Guide

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Catalyst 4500 Series Switch Cisco IOS Command Reference—Release IOS XE 3.4.0SG and IOS 15.1(2)SG)
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Chapter 2 Cisco IOS Commands for the Catalyst 4500 Series Switches
ip dhcp snooping information option allow-untrusted
ip dhcp snooping information option allow-untrusted
To allow DHCP packets with option 82 data inserted to be received from a snooping untrusted port, use
the ip dhcp snooping information option allow-untrusted command. To disallow receipt of these
DHCP packets, use the no form of this command.
ip dhcp snooping information option allow-untrusted
no ip dhcp snooping information option allow-untrusted
Syntax Description This command has no arguments or keywords.
Defaults DHCP packets with option 82 are not allowed on snooping untrusted ports.
Command Modes Global configuration mode
Command History
Examples This example shows how to allow DHCP packets with option 82 data inserted to be received from a
snooping untrusted port:
Switch# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# ip dhcp snooping information option allow-untrusted
Switch(config)# end
Switch#
Related Commands
Release Modification
12.2(25)EWA Support for this command was introduced on the Catalyst 4500 series switch.
Command Description
ip dhcp snooping Globally enables DHCP snooping.
ip dhcp snooping information option Enables DHCP option 82 data insertion.
ip dhcp snooping limit rate Configures the number of the DHCP messages that an
interface can receive per second.
ip dhcp snooping trust Enables DHCP snooping on a trusted VLAN.
ip dhcp snooping vlan Enables DHCP snooping on a VLAN or a group of VLANs.
show ip dhcp snooping Displays the DHCP snooping configuration.
show ip dhcp snooping binding Displays the DHCP snooping binding entries.

Cisco Catalyst 4500 Series Specifications

General

Series	Catalyst 4500 Series
Category	Switch
Layer Support	Layer 2, Layer 3
Form Factor	Modular chassis
Stackable	No
Chassis Slots	3, 6, 7, 10
Power Supply Options	AC, DC
Redundancy	Power supply, Supervisor engine
Network Management	Cisco IOS Software CLI, SNMP, Cisco Prime Infrastructure
Features	Security, QoS
Port Density	Up to 384 ports per chassis
Security Features	802.1X, ACLs, DHCP Snooping, Dynamic ARP Inspection, IP Source Guard
Supervisor Engine	8-E