H3C Technologies H3C SR8800 - Manual (Page 359)

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Configuring IPv6 BGP
NOTE:
•
The term router in this document refers to both routers and Layer 3 switches.
• This chapter describes only configuration for IPv6 BGP. For BGP related information, see the chapter
“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:
• 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
Complete the following tasks to configure IPv6 BGP:
Task Remarks
Configuring IPv6 BGP basic
functions
Specifying an IPv6 BGP peer Required
Injecting a local IPv6 route Optional
Configuring a preferred value for routes from a
peer/peer group
Optional
Specifying the source interface for establishing TCP
connections
Optional
Allowing the establishment of a non-direct EBGP
connection
Optional
Configuring a description for an IPv6 peer/peer
group
Optional