Multichassis Link Aggregation for IPv6 Through NDP
Neighbor Discovery Protocol (NDP) is an IPv6 protocol that enables nodes on the same link to advertise their existence to their neighbors and to learn about the existence of their neighbors. NDP is built on top of Internet Control Message Protocol version 6 (ICMPv6). It replaces the following IPv4 protocols: Router Discovery (RDISC), Address Resolution Protocol (ARP), and ICMPv4 redirect.
You can use NDP in a multichassis link aggregation group (MC-LAG) active-active configuration on switches.
Neighbor Discovery Messages for MC-LAGs
NDP on MC-LAGs uses the following message types:
Neighbor solicitation (NS)—Messages used for address resolution and to test reachability of neighbors.
A host can verify that its address is unique by sending a neighbor solicitation message destined to the new address. If the host receives a neighbor advertisement in reply, the address is a duplicate.
Neighbor advertisement (NA)—Messages used for address resolution and to test reachability of neighbors. Neighbor advertisements are sent in response to neighbor solicitation messages.
NDP Functions and Configuration Requirements on MC-LAGs
The functions provided through NDP on MC-LAGs on the switches are:
Address resolution
Neighbor unreachability detection
The requirements for an NDP configuration on MC-LAG on the switches include:
An active-active configuration
Virtual Router Redundancy Protocol (VRRP)
