User guide

Configuring BGP Configuring BGP for IPv6
OmniSwitch AOS Release 7 Advanced Routing Configuration Guide March 2015 page 4-63
BGP Peer Behavior using Local IPv6 Unicast Addresses
• The local IPv6 address prefixes are exchanged between internal BGP (IBGP) speakers within the same
Autonomous System (AS), unless denied by explicit policy configuration.
• As Exterior BGP (EBGP) peers between different AS ignore receipt of and do not advertise prefixes
with the well-known FC00::/7 prefix, prefixes longer than FC00::/7 can be configured for inter-site
communication.
• There may be specific /48 or longer routes created for one or more Local IPv6 prefixes. In such a case,
explicit BGP configuration of peer policies must be configured to control learning/advertising of such
prefixes.
Configuring an IPv4 BGP Peer to Exchange IPv6 Prefixes
A BGP peer that is identified by its IPv4 address can be used to exchange IPv6 prefixes. However, to do
this both the peers should be enabled with IPv6 BGP unicast and should have interfaces that support IPv6
addresses. To configure an IPv4 BGP peer to exchange IPv6 prefixes, follow the steps mentioned below:
1 Create an IPv4 BGP peer with which the BGP speaker will establish peering using its IPv4 address
with the ip bgp neighbor command, as shown:
-> ip bgp neighbor 190.17.20.16
2 Assign an AS number to the IPv4 peer using the ip bgp neighbor remote-as command. For example,
to assign the peer created in Step 1 to AS number 200, you would enter:
-> ip bgp neighbor 190.17.20.16 remote-as 200
Enables or disables the stripping
of private autonomous system
numbers from the AS path of
routes destined to this peer.
ipv6 bgp neighbor remove-private-as disabled
Enables or disables BGP peer
soft reconfiguration.
ipv6 bgp neighbor soft-reconfiguration enabled
Configures this peer as a member
of the same confederation as the
local BGP speaker.
ip bgp confederation neighbor disabled
Configures the local transport
endpoint address for this
neighbor's peering session.
ipv6 bgp neighbor update-source Not set until configured
Configures the local IPv6
interface from which the peer
will be connected if the peer is
configured with its link-local
address.
ipv6 bgp neighbor update-source-
address
Not set until configured
Configures the IPv4 next hop
addresses for IPv4 prefixes
advertised between BGP peers.
ipv6 bgp neighbor ipv4-nexthop IPv4 next hop value is set
to all zeros.
Parameter Description Command
Default Value/
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