H3C Technologies H3C SecPath F1000-E - Manual (Page 812)

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Configuring a preferred value for routes from a peer/peer
group
If you both reference a routing policy and use the command peer { ipv6-group-name | ipv6-address }
preferred-value value to set a preferred value for routes from a peer, the routing policy sets the specific
preferred value for routes matching it. If the preferred value in the routing policy is zero, the routes use the
value set with the peer { ipv6-group-name | ipv6-address } preferred-value value command. For how to
use a routing policy to set a preferred value, see the command peer { group-name | ipv6-address }
route-policy route-policy-name { import | export } in this chapter, and the command apply
preferred-value preferred-value in Network Management Command Reference.
To configure a preferred value for routes from a peer/peer group:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter BGP view. bgp as-number N/A
3. Enter IPv6 address family view
or IPv6 BGP-VPN instance
view.
ipv6-family [ vpn-instance
vpn-instance-name ]
N/A
4. Configure a preferred value
for routes received from an
IPv6 peer/peer group.
peer { ipv6-group-name |
ipv6-address } preferred-value
value
By default, the preferred value is 0.
Specifying the source interface for establishing TCP
connections
IPv6 BGP uses TCP as the transport layer protocol. By default, IPv6 BGP uses the outgoing interface of the
optimal route to a peer/peer group as the source interface for establishing TCP connections to the
peer/peer group.
To establish a BGP connection, you need to specify on the local router the source interface for
establishing the TCP connection to the peer on the peering BGP router; otherwise, the local BGP router
may fail to establish TCP connection to the peer when you use the outgoing interface of the best route as
the source interface.
If an IPv6 BGP router has multiple links to a peer, and the source interface fails, IPv6 BGP has to
reestablish TCP connections, causing network oscillation. To enhance stability of IPv6 BGP connections,
H3C recommends using a loopback interface as the source interface.
To specify the source interface for establishing TCP connections to a BGP peer or peer group:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter BGP view. bgp as-number N/A
3. Enter IPv6 address family
view.
ipv6-family N/A