Service Manual
Neighbor Discovery Protocol (NDP)
The neighbor discovery protocol for IPv6 is dened in RFC 2461 as part of the Stateless Address Autoconguration protocol. It replaces the
Address Resolution Protocol used with IPv4. NDP denes mechanisms for solving the following problems:
• Router discovery — hosts can locate routers residing on a link
• Prex discovery — hosts can discover address prexes for the link
• Parameter discovery
• Address autoconguration — conguration of addresses for an interface
• Address resolution — mapping from IP address to link-layer address
• Next-hop determination
• Neighbor unreachability detection (NUD) — determine that a neighbor is no longer reachable on the link.
• Duplicate address detection (DAD) — allow a node to check whether a proposed address is already in use.
• Redirect — the router can inform a node about a better rst-hop.
NDP uses the following ve ICMPv6 packet types in its implementation:
• Router Solicitation
• Router Advertisement
• Neighbor Solicitation
• Neighbor Advertisement
• Redirect
Topics:
• clear ipv6 neighbors
• ipv6 neighbor
• show ipv6 neighbors
• IPv6 Router Advertisement (RA) Guard
clear ipv6 neighbors
Delete all entries in the IPv6 neighbor discovery cache or neighbors of a specic interface. Static entries are not removed using this
command.
Syntax
clear ipv6 neighbors [vrf vrf-name] [ipv6-address | interface]
Parameters
vrf vrf-name (OPTIONAL) Enter the keyword vrf followed by the name of the VRF to clear the
neighbor corresponding to that VRF.
NOTE: If you do not specify this option, the neighbors in the default VRF are
cleared.
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Neighbor Discovery Protocol (NDP) 1051