CLI Reference Guide-R01

Chapter 30 | IP Interface Commands
IPv6 Interface
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Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
◆ IPv6 Router Advertisements (RA) convey information that enables nodes to
auto-configure on the network. This information may include the default router
address taken from the observed source address of the RA message, as well as
on-link prefix information. However, unintended mis-configurations, or
possibly malicious attacks on the network, may lead to bogus RAs being sent,
which in turn can cause operational problems for hosts on the network.
◆ This command can be used to block RAs and Router Redirect (RR) messages on
the specified interface. Determine which interfaces are connected to known
routers, and enable RA Guard on all other untrusted interfaces.
Example
Console(config)#interface ethernet 1/1
Console(config-if)#ipv6 nd raguard
Console(config-if)#
show ipv6 nd raguard This command displays the configuration setting for RA Guard.
Syntax
show ipv6 nd raguard [interface]
interface
ethernet unit/port
unit - Unit identifier. (Range: 1)
port - Port number. (Range: 1-28)
port-channel channel-id (Range: 1-28)
Command Mode
Privileged Exec
Example
Console#show ipv6 nd raguard interface ethernet 1/1
Interface RA Guard
--------- --------
Eth 1/ 1 Yes
Console#