F3215-HP Load Balancing Module Appendix Protocol Reference-6PW101

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To support multiple network layer protocols, MP-BGP defines the following path attributes:
• MP_REACH_NLRI—Multiprotocol Reachable NLRI, for carrying prefixes of feasible routes and next
hops for multiple network layer protocols. Such routes can then be advertised.
• MP_UNREACH_NLRI—Multiprotocol Unreachable NLRI, for carrying prefixes of unfeasible routes
for multiple network layer protocols. Such routes can then be withdrawn.
MP-BGP uses these attributes to advertise feasible and unfeasible routes of different network layer
protocols. BGP speakers not supporting MP-BGP ignore updates containing these attributes and do not
forward them to its peers.
The system supports multiple MP-BGP extensions, such as IPv6 extension (see Network Management
Configuration Guide.)
Address family
MP-BGP uses address families and subsequent address families to differentiate network layer protocols of
routes contained in the MP_REACH_NLRI and MP_UNREACH_NLRI attributes. For example, an Address
Family Identifier (AFI) of 2 and Subsequent Address Family Identifier (SAFI) of 1 indicates IPv6 unicast
routing information carried in the MP_REACH_NLRI attribute. For address family values, see RFC 1700.
BGP configuration views
Table 4 shows views for different address families supported by BGP. This chapter describes
configurations in BGP view.
Table 4 BGP configuration views
View names Ways to enter the views Remarks
BGP view
<Sysname> system-view
[Sysname] bgp 100
[Sysname-bgp]
Configurations in this view are effective for
routes in all address families and VPN
instances (such as confederation, GR, and
NSR), or for IPv4 unicast routes on the
public network (such as local route
advertisement, IGP route redistribution,
route summarization, and BGP route
distribution/reception filtering policies).
IPv6 address family view
<Sysname> system-view
[Sysname] bgp 100
[Sysname-bgp]
ipv6-family
[Sysname-bgp-af-ipv6]
Configurations in this view are effective
only for IPv6 unicast routes on the public
network.
IPv6 BGP-VPN instance view
<Sysname> system-view
[Sysname] bgp 100
[Sysname-bgp]
ipv6-family vpn-instance
vpn1
[Sysname-bgp-ipv6-vpn1]
Configurations in this view are effective
only for IPv6 unicast routes in the specified
VPN instance.
Protocols and standards
• RFC 1700, ASSIGNED NUMBERS