Cisco Broadband Cable Command Reference Guide

Chapter 5 Cable CPE Commands
ip dhcp smart-relay
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Cisco Broadband Cable Command Reference Guide
ip dhcp smart-relay
To enable the DHCP smart-relay feature, use the ip dhcp smart-relay command in global configuration
mode. To disable this feature, use the no form of this command.
Cisco uBR905, uBR924, uBR925 cable access routers, Cisco CVA122 Cable Voice Adapter
ip dhcp smart-relay
no ip dhcp smart-relay
Syntax Description This command has no arguments or keywords.
Defaults DHCP smart-relay is enabled by default.
Command Modes Global configuration
Command History
Release Modification
12.1(3a)EC This command was introduced for the Cisco uBR7200 series universal
broadband router.
12.1(3)T Support was added for the Cisco uBR924 cable access router.
12.1(3)XL Support was added for the Cisco uBR905 cable access router.
12.1(3)XU1 Support was added for the Cisco CVA122 Cable Voice Adapter.
12.2(2)XA Support was added for the Cisco uBR925 cable access router.
Usage Guidelines The DHCP smart-relay feature enables a CM to automatically switch to a secondary DHCP server if the
primary DHCP server cannot provide the requested IP address. If a DHCP Relay Agent is specified in
the DOCSIS configuration file that the router downloads during its initial provisioning, the secondary
server can reside on a separate subnet.
The DHCP smart-relay feature is enabled by default, so this command is not normally needed. However,
if DHCP clients send multiple DHCP request messages at the same time, use the no ip dhcp smart-relay
command to disable this feature, so that the primary DHCP server has sufficient time to respond to the
initial client requests.
Examples The following example shows how to enable the DHCP smart-relay feature:
Router(config)# ip dhcp smart-relay
The following example shows how to disable the DHCP smart-relay feature, which would be done when
the DHCP clients send multiple DHCP request messages at the same time:
Router(config)# ip dhcp smart-relay
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