Ip Dhcp Relay Information Option - Cisco SR2016T-NA Reference Manual

Chapter 2 Cisco CMTS Configuration Commands

ip dhcp relay information option

To configure the Cisco CMTS so that it inserts the MAC address of a CM into the DHCP packet received
from a CM or host before it forwards the packet to a DHCP server, use the ip dhcp relay information
option in global configuration mode. To disable the MAC address insertion, use the no form of this
command.
Syntax Description This command has no keywords or arguments.
Defaults no ip dhcp relay info option
Command Modes
Global configuration
Command History Release
12.0(1)T
12.0(7)XR2, 12.1(T),
12.1(2)EC1,
12.0(10)SC
Usage Guidelines
This functionality enables a DHCP server to identify the user (CM) sending the request. When this
option is enabled, the CMTS inserts the DHCP relay agent information option (also called option 82),
which contains the CM or host MAC address, in forwarded BOOTREQUEST messages.
Examples
The following example shows how to enable the insertion of DHCP relay agent information into DHCP
packets:
Router# configure terminal
Router(config)# ip dhcp relay information option
Related Commands Command
cable dhcp-giaddr
cable helper-address
OL-1581-08
ip dhcp relay information option
no ip dhcp relay information option
Modification
This command was introduced for non-CMTS platforms.
This command was supported for the Cisco uBR7200 series routers,
replacing the
previous Cisco IOS releases for this purpose.
cable relay-agent-option
Description
Modifies the GIADDR field of DHCPDISCOVER and
DHCPREQUEST packets with a Relay IP address before they are
forwarded to the DHCP server.
Specifies a destination IP address for User Datagram Protocol (UDP)
broadcast (DHCP) packets.
Cisco Broadband Cable Command Reference Guide
ip dhcp relay information option
command, which was used in
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