Chapter 23 Configuring Dhcp Features And Ip Source Guard; Understanding Dhcp Snooping - Cisco IE-3000-8TC Software Configuration Manual

Configuring DHCP Features and IP Source Guard
This chapter describes how to configure DHCP snooping and option-82 data insertion, and the DHCP
server port-based address allocation features on the IE 3000 switch. It also describes how to configure
the IP source guard feature.
For complete syntax and usage information for the commands used in this chapter, see the command
Note
reference for this release, and see the "DHCP Commands" section in the Cisco IOS IP Command
Reference, Volume 1 of 3: Addressing and Services, Release 12.2 from the Cisco.com page under
Documentation > Cisco IOS Software > 12.2 Mainline > Command References.
This chapter consists of these sections:
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Understanding DHCP Snooping

DHCP is widely used in LAN environments to dynamically assign host IP addresses from a centralized
server, which significantly reduces the overhead of administration of IP addresses. DHCP also helps
conserve the limited IP address space because IP addresses no longer need to be permanently assigned
to hosts; only those hosts that are connected to the network consume IP addresses.
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OL-13018-03
Understanding DHCP Snooping, page 23-1
Configuring DHCP Snooping, page 23-6
Displaying DHCP Snooping Information, page 23-12
Understanding IP Source Guard, page 23-12
Configuring IP Source Guard, page 23-13
Displaying IP Source Guard Information, page 23-15
Understanding DHCP Server Port-Based Address Allocation, page 23-15
Configuring DHCP Server Port-Based Address Allocation, page 23-16
Displaying DHCP Server Port-Based Address Allocation, page 23-19
DHCP Server, page 23-2
DHCP Relay Agent, page 23-2
DHCP Snooping, page 23-2
Option-82 Data Insertion, page 23-3
DHCP Snooping Binding Database, page 23-5
C H A P T E R
Cisco IE 3000 Switch Software Configuration Guide
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