CHAPT ER
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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
OL-10101-02
19
Configuring DHCP Features
This chapter describes how to configure DHCP snooping and the option-82 data insertion features on the
Catalyst 2950 or Catalyst 2955 switch.
Note For complete syntax and usage information for the commands used in this chapter, see the command
reference for this release, and see the “IP Addressing and Services” section in the Cisco IOS IP and IP
Routing Command Reference, Release 12.1.
This chapter consists of these sections:
Understanding DHCP Features, page 19-1
Configuring DHCP Features, page 19-5
Displaying DHCP Information, page 19-8

Understanding DHCP Features

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.
The switch supports these DHCP features:
DHCP Server, page 19-2
DHCP Relay Agent, page 19-2
DHCP Snooping, page 19-2
Option-82 Data Insertion, page 19-3
For information about the DHCP client, see the “IP Addressing and Services” section in the Cisco IOS
IP and IP Routing Configuration Guide, Release 12.1.