CLI Guide

Layer 3 Routing Commands 1845
ip irdp multicast
To send router advertisements as IP multicast packets, use the ip irdp
multicast command in Interface Configuration mode. To send router
advertisements to the limited broadcast address (255.255.255.255), use the
no form of this command.
Syntax
ip irdp multicast
no ip irdp multicast
Default Configuration
Router discovery packets are sent to the all hosts IP multicast address
(224.0.0.1) by default.
Command Mode
Interface Configuration (VLAN) mode
User Guidelines
If a subnet includes any hosts that do not accept IP multicast packets, send
router advertisements to the limited broadcast address.
Example
The following example configures router discovery to send to the limited
broadcast address:
console(config)#interface vlan 15
console(config-if-vlan15)#ip irdp multicast
ip irdp preference
Use the ip irdp preference command in Interface Configuration mode to
configure the preference of the address as a default router address relative to
other router addresses on the same subnet. Use the no form of the command
to set the preference to the default value.