Cisco Catalyst 4500 Series, Software Configuration Manual

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Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 59 Configuring the Cisco IOS DHCP Server
Configuring DHCP Address Pools
Configuring DHCP Address Allocation Using Option 82
• Enabling Option 82 for DHCP Address Allocation, page 59-21
•
Defining the DHCP Class and Relay Agent Information Patterns, page 59-21
Enabling Option 82 for DHCP Address Allocation
By default, the Cisco DHCP server uses information provided by option 82 to allocate IP addresses. If
the DHCP address allocation is disabled, perform the task described in this section to reenable this
capability.
Troubleshooting Tips
If DHCP classes are configured in the pool, but the DHCP server does not use the classes, verify if the
no ip dhcp use class command was configured.
Defining the DHCP Class and Relay Agent Information Patterns
Before You Begin
You must know the hexadecimal value of each byte location in option 82 to configure the
relay-information hex command. The option 82 format may vary from product to product. Contact the
relay agent vendor for this information.
Perform this task to define the DHCP class and relay agent information patterns.
Step 9
Switch(config-if)# end
Exits interface configuration mode and returns to privileged
EXEC mode.
Step 10
Switch# show ip dhcp import
Displays the options that are imported from the central DHCP
server.
Command or Action Purpose
Command or Action Purpose
Step 1
Switch> enable
Enables privileged EXEC mode.
• Enter your password if prompted.
Step 2
Switch#
configure terminal
Enters global configuration mode.
Step 3
Switch(config)# ip dhcp use class
Controls DHCP classes that are used for address allocation.
• This functionality is enabled by default.
•
Use the no form of this command to disable this functionality
without deleting the DHCP class configuration.
Step 4
Switch(config)# end
Exits global configuration mode and returns to privileged EXEC
mode.