H3C Technologies H3C S12500 Series Switches - Manual (Page 371)

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Configuring IPv6 BGP
This chapter describes only configuration for IPv6 BGP. For BGP-related information, see "Configuring
BGP."
IPv6 BGP overview
BGP-4 was designed to carry only IPv4 routing information, and other network layer protocols, such as
IPv6, are not supported.
To support multiple network layer protocols, IETF extended BGP-4 by introducing Multiprotocol BGP
(MP-BGP), which is defined in RFC 2858 (multiprotocol extensions for BGP-4).
MP-BGP for IPv6 is called "IPv6 BGP" for short.
IPv6 BGP puts IPv6 network layer information into the attributes of Network Layer Reachability
Information (NLRI) and NEXT_HOP.
The NLRI attribute of IPv6 BGP involves the following:
• MP_REACH_NLRI—Multiprotocol Reachable NLRI, for advertising reachable route and next hop
information.
• MP_UNREACH_NLRI—Multiprotocol Unreachable NLRI, for withdrawal of unreachable routes.
The NEXT_HOP attribute of IPv6 BGP is identified by an IPv6 unicast address or IPv6 local link address.
IPv6 BGP has the same messaging and routing mechanisms as BGP.
IPv6 BGP configuration task list
Task Remarks
Configuring basic IPv6 BGP
Specifying an IPv6 BGP peer Required.
Injecting a local IPv6 route Optional.
Configuring a preferred value for routes from a
peer or peer group
Optional.
Specifying the source interface for establishing TCP
connections
Optional.
Allowing the establishment of an indirect EBGP
connection
Optional.
Configuring a description for an IPv6 peer or peer
group
Optional.
Disabling session establishment to an IPv6 peer or
peer group
Optional.
Logging IPv6 peer or peer group state changes Optional.
Controlling route distribution
and reception
Configuring IPv6 BGP route redistribution Optional.
Configuring IPv6 BGP route summarization Optional.