Cisco Catalyst 4500 Series Software Configuration Guide

60-19
Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 60 Configuring DHCP Snooping, IP Source Guard, and IPSG for Static Hosts
About IP Source Guard
Displaying a Binding Table
The DHCP snooping binding table for each switch contains binding entries that correspond to untrusted
ports. The table does not contain information about hosts interconnected with a trusted port because each
interconnected switch has its own DHCP snooping binding table.
This example shows how to display the DHCP snooping binding information for a switch:
Switch# show ip dhcp snooping binding
MacAddress IpAddress Lease(sec) Type VLAN Interface
------------------ --------------- ---------- ------------- ---- --------------------
00:02:B3:3F:3B:99 55.5.5.2 6943 dhcp-snooping 10 FastEthernet6/10
Switch#
Table 60-2 describes the fields in the show ip dhcp snooping binding command output.
Displaying the DHCP Snooping Configuration
This example shows how to display the DHCP snooping configuration for a switch:
Switch# show ip dhcp snooping
Switch DHCP snooping is enabled.
DHCP Snooping is configured on the following VLANs:
10 30-40 100 200-220
Insertion of option 82 is enabled
Option82 on untrusted port is not allowed
Verification of hwaddr field is enabled
Interface Trusted Rate limit (pps)
--------- ------- ----------------
FastEthernet2/1 yes 10
FastEthernet3/1 yes none
GigabitEthernet1/1 no 20
Switch#
About IP Source Guard
The IP source guard feature is enabled on a DHCP snooping untrusted Layer 2 port. Initially, all IP traffic
on the port is blocked except for DHCP packets that are captured by the DHCP snooping process. When
a client receives a valid IP address from the DHCP server, or when you configure a static IP source
binding, a per-port and VLAN access control list (VACL) is installed on the port. This process restricts
Table 60-2 show ip dhcp snooping binding Command Output
Field Description
MAC Address Client hardware MAC address
IP Address Client IP address assigned from the DHCP server
Lease (seconds) IP address lease time
Type Binding type; dynamic binding learned by DHCP snooping or
statically-configured binding.
VLAN VLAN number of the client interface
Interface Interface that connects to the DHCP client host

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