130 Brocade ICX 6650 Administration Guide
53-1002600-01
IPv6 neighbor discovery configuration
5
•Interval between router advertisement messages.
•Value that indicates a router is advertised as a default router (for use by all nodes on a
given link).
•Prefixes advertised in router advertisement messages.
•Flags for host stateful autoconfiguration.
•Amount of time during which an IPv6 node considers a remote node reachable (for use by all
nodes on a given link).
IPv6 neighbor discovery configuration notes
NOTE
For all solicitation and advertisement messages, Brocade uses seconds as the unit of measure
instead of milliseconds.
•If you add a port to a port-based VLAN, and the port has IPv6 neighbor discovery configuration,
the system will clean up the neighbor discovery configuration from the port and display the
following message on the console.
ND6 port config on the new member ports removed
•Neighbor discovery is not supported on tunnel interfaces.
Neighbor solicitation and advertisement messages
Neighbor solicitation and advertisement messages enable a node to determine the link-layer
address of another node (neighbor) on the same link. (This function is similar to the function
provided by the Address Resolution Protocol [ARP] in IPv4.) For example, node 1 on a link wants to
determine the link-layer address of node 2 on the same link. To do so, node 1, the source node,
multicasts a neighbor solicitation message. The neighbor solicitation message, which has a value
of 135 in the Type field of the ICMP packet header, contains the following information:
•Source address: IPv6 address of node 1 interface that sends the message.
•Destination address: solicited-node multicast address (2001:DB8:0:0:0:1:FF00::/104) that
corresponds the IPv6 address of node 2.
•Link-layer address of node 1.
•A query for the link-layer address of node 2.
After receiving the neighbor solicitation message from node 1, node 2 replies by sending a
neighbor advertisement message, which has a value of 136 in the Type field of the ICMP packet
header. The neighbor solicitation message contains the following information:
•Source address: IPv6 address of the node 2 interface that sends the message.
•Destination address: IPv6 address of node 1.
•Link-layer address of node 2.
After node 1 receives the neighbor advertisement message from node 2, nodes 1 and 2 can now
exchange packets on the link.
After the link-layer address of node 2 is determined, node 1 can send neighbor solicitation
messages to node 2 to verify that it is reachable. Also, nodes 1, 2, or any other node on the same
link can send a neighbor advertisement message to the all-nodes multicast address (2001:DB8:1)
if there is a change in their link-layer address.