H3C Technologies H3C S7500E Series Switches - Manual (Page 265)

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The PEs and ASBR PEs in an AS must be able to exchange labeled IPv4 routes.
Follow these steps to configure a PE for inter-provider VPN option C:
To do… Use the command… Remarks
Enter system view system-view —
Enter BGP view bgp as-number —
Configure the ASBR PE in the
same AS as the IBGP peer
peer { group-name | ip-address }
as-number as-number
Required
Enable the PE to exchange
labeled IPv4 routes with the ASBR
PE in the same AS
peer { group-name | ip-address }
label-route-capability
Required
By default, the device does not
advertise labeled routes to the
IPv4 peer/peer group.
Configure the PE of another AS as
the EBGP peer
peer { group-name | ip-address }
as-number as-number
Required
Enter BGP-VPNv4 subaddress
family view
ipv4-family vpnv4 —
Enable the PE to exchange BGP
VPNv4 routing information with the
peer
peer { group-name | ip-address }
enable
Required
Configure the PE not to change
the next hop of a route when
advertising it to the EBGP peer
peer { group-name | ip-address }
next-hop-invariable
Optional
Required only when RRs are used
to advertise VPNv4 routes, where
the next hop of a route advertised
between RRs cannot be changed.
Configuring the ASBR PEs
In the inter-provider VPN option C solution, an inter-provider VPN LSP is required, and the routes
advertised between the relevant PEs and ASBRs must carry MPLS label information.
An ASBR-PE establishes common IBGP peer relationship with PEs in the same AS, and common
EBGP peer relationship with the peer ASBR PE. All of them exchange labeled IPv4 routes.
The public routes carrying MPLS labels are advertised through MP-BGP. According to RFC 3107
“Carrying Label Information in BGP-4”, the label mapping information for a particular route is
piggybacked in the same BGP update message that is used to distribute the route itself. This
capability is implemented through BGP extended attributes and requires that the BGP peers can
handle labeled IPv4 routes.
Follow these steps to configure an ASBR PE for inter-provider VPN option C:
To do… Use the command… Remarks
Enter system view system-view —