H3C Technologies H3C S5560 Series Switches - Manual (Page 229)

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Step Command Remarks
4. Add a peer into the EBGP
peer group.
peer ipv6-address [ prefix-length ]
group group-name as-number
as-number
By default, no peer exists in the
peer group.
BGP can use an IPv6 link-local
address to establish a peer
relationship with a peer when the
following conditions exist:
• The IPv6 link-local address
belongs to the interface directly
connected to the local router.
• The peer connect-interface
command is configured on the
peer to specify the interface as
the source interface.
5. (Optional.) Configure a
description for the peer group. peer group-name description
description-text By default, no description is
configured for the peer group.
6. Create the BGP IPv6 unicast
address family or BGP-VPN
IPv6 unicast address family
and enter its view.
address-family ipv6 [ unicast ]
By default, the BGP IPv6 unicast
address family or BGP-VPN IPv6
unicast address family is not
created.
7. Enable the router to exchange
IPv6 unicast routing
information with peers in the
specified peer group.
peer group-name enable
By default, the router cannot
exchange IPv6 unicast routing
information with the peers.
Specifying the source interface for TCP connections
By default, BGP uses the output interface of the optimal route to a peer or peer group as the source
interface for establishing TCP connections to the peer or peer group, and it uses the IP address/IPv6
address of the output interface as the source IP address/IPv6 address of TCP connections. You can
change the source interface in the following scenarios:
• If the peer's IP/IPv6 address belongs to an interface indirectly connected to the local router, specify
that interface as the source interface for TCP connections on the peer. For example, interface A on
the local end is directly connected to interface B on the peer. If you use the peer x.x.x.x as-number
as-number command on the local end, and x.x.x.x is not the IP address of interface B, you must do
the following:
a. Use the peer connect-interface command on the peer.
b. Specify the interface whose IP address is x.x.x.x as the source interface.
BGP can use an IPv6 link-local address to establish a peer relationship with a peer when the
following conditions exist:
{
The IPv6 link-local address belongs to the interface directly connected to the local router.
{
The peer connect-interface command is configured on the peer to specify the interface as the
source interface.
• If the source interface fails on a BGP router that has multiple links to a peer, BGP must re-establish
TCP connections. To avoid this problem, use a loopback interface as the source interface.
• To establish multiple BGP sessions between two routers, specify the source interface for establishing
TCP connections to each peer on the local router. Otherwise, the local BGP router may fail to