Administrator Guide

Layer 3 Routing Commands 1557
Command Mode
Interface Configuration (VLAN, Tunnel, Loopback) mode
User Guidelines
The router advertises its global IPv6 prefixes in its router advertisements
(RAs). An RA only includes the prefixes of the IPv6 addresses configured on
the interface where the RA is transmitted. Addresses are configured using the
ipv6 address interface configuration command. Each prefix advertisement
includes information about the prefix, such as its lifetime values and whether
hosts should use the prefix for on-link determination or address auto-
configuration. Use the ipv6 nd prefix command to configure these values.
The ipv6 nd prefix command will allow you to preconfigure RA prefix values
before you configure the associated interface address. In order for the prefix
to be included in RAs, you must configure an address that matches the prefix
using the ipv6 address command. Prefixes specified using ipv6 nd prefix
without an associated interface address will not be included in RAs and will
not be committed to the device configuration.
Example
The following example sets the IPv6 prefixes to include in the router
advertisement.
console(config)#interface vlan 11
console(config-if-vlan11)#ipv6 nd prefix 2020:1::1/64
ipv6 nd raguard attach-policy
Use this command to enable RA Guard policy on an interface. Use the no
form of the command to disable RA-Guard.
Syntax
ipv6 nd raguard attach-policy
no ipv6 nd raguard attach-policy
Default Configuration
By default, no RA guard policies are applied to any interface.