IBM RackSwitch G8000, Application Manual

Page: 199 / 362

© Copyright IBM Corp. 2011 Chapter 16. Internet Protocol Version 6
197
Neighbor Discovery
Neighbor Discovery Overview
The switch uses Neighbor Discovery protocol (ND) to gather information about other
router and host nodes, including the IPv6 addresses. Host nodes use ND to
configure their interfaces and perform health detection. ND allows each node to
determine the link-layer addresses of neighboring nodes, and to keep track of each
neighbor’s information. A neighboring node is a host or a router that is linked directly
to the switch. The switch supports Neighbor Discovery as described in RFC 4861.
Neighbor Discover messages allow network nodes to exchange information, as
follows:
•
Neighbor Solicitations allow a node to discover information about other nodes.
• Neighbor Advertisements are sent in response to Neighbor Solicitations. The
Neighbor Advertisement contains information required by nodes to determine the
link-layer address of the sender, and the sender’s role on the network.
• IPv6 hosts use Router Solicitations to discover IPv6 routers. When a router
receives a Router Solicitation, it responds immediately to the host.
• Routers uses Router Advertisements to announce its presence on the network,
and to provide its address prefix to neighbor devices. IPv6 hosts listen for Router
Advertisements, and uses the information to build a list of default routers. Each
host uses this information to perform autoconfiguration of IPv6 addresses.
• Redirect messages are sent by IPv6 routers to inform hosts of a better first-hop
address for a specific destination. Redirect messages are only sent by routers for
unicast traffic, are only unicast to originating hosts, and are only processed by
hosts.
ND configuration for general advertisements, flags, and interval settings, as well as
for defining prefix profiles for router advertisements, is performed on a per-interface
basis using the following command path:
To add or remove entries in the static neighbor cache, use the following command
path:
To manage IPv6 prefix policies, use the following command path:
RS G8000(config)#
interface ip
<interface number>
RS G8000(config-ip-if)# [
no
]
ipv6 nd ?
RS G8000(config-ip-if)#
exit
RS G8000(config)# [
no
]
ip neighbors ?
RS G8000(config)# [
no
]
ip prefix-policy ?