Cisco Cisco IOS Software Release 12.4(11)T

© 2006 Cisco Systems, Inc. All rights reserved.

This feature introduces support for DHCP relay agent information option (option 82) on stacked 
EtherSwitch network modules. This functionality is also available on standalone EtherSwitch network 
modules.

Automatic DHCP address allocation is typically based on an IP address, either the gateway IP address 
or the incoming interface IP address. In some networks, it is necessary to use additional information to 
further determine which IP addresses to allocate. By using the relay agent information option 
(option 82), the Cisco IOS relay agent can include additional information about itself when forwarding 
client-originated DHCP packets to a DHCP server. 

Configuration information is included in the “EtherSwitch Network Module” module of the Cisco IOS 
Interface and Hardware Component Configuration Guide, Release 12.4T,

at the following URL:

The following sections provide information about this feature:

DHCP Option 82 Relay Agent on Stacked EtherSwitch Network Modules

Configuring DHCP Address Allocation Using Option 82

Configuring DHCP Option 82 Relay Agent on EtherSwitch Network Modules: Example

For a complete list of features included in the “EtherSwitch Network Module” module, see the Feature 
Information Table located toward the end of the module.

There are no new or modified for this feature.

An alphabetical list of all Cisco IOS Release 12.4T commands is in the Cisco IOS Master Commands 
List, Release 12.4T, at the following URL: