Huawei AR1200 Series - Page 173

4. Configure the BGP AS number substitution on the PE.
Data Preparation
To configure the BGP AS number substitution, you need the following data:
l MPLS LSR-IDs of the PE and the P
l The VPN instances created on the PE1 and PE2
l The same AS number used by the CE1 and the CE2 (It is different from the AS number of
the backbone network.)
Procedure
Step 1 Configure basic BGP/MPLS IP VPN.
The configuration of basic BGP/MPLS IP VPN includes:
l Configure OSPF on the MPLS backbone network. PE and P can learn routes of the Loopback
interface from each other.
l Configure MPLS basic capability and MPLS LDP on the MPLS backbone network to
establish LDP LSP.
l Establish the MP-IBGP neighbor between PEs to advertise VPN-IPv4 routes.
l Configure the VPN instances of VPN1 on PE2 and associate it with CE2.
l Configure the VPN instances of VPN1 on PE1 and associate it with CE1.
l Configure BGP between PE1 and CE1, and between PE2 and CE2 to import CEs routes into
PEs.
After the configuration given above, run the display ip routing-table command on CE2. It
shows that CE2 can learn the route of the network segment (10.1.1.0/24) of the interface on CE1
that is connected with PE1. There is no route to the VPN site (100.1.1.0/24) of the CE1. The
same situation occurs on CE1.
[CE2] display ip routing-table
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Routing Tables: Public
Destinations : 9 Routes : 9
Destination/Mask Proto Pre Cost Flags NextHop Interface
10.1.1.0/24 EBGP 255 0 D 10.2.1.2 GigabitEthernet1/0/0
10.1.1.1/32 EBGP 255 0 D 10.2.1.2 GigabitEthernet1/0/0
10.2.1.0/24 Direct 0 0 D 10.2.1.1 GigabitEthernet1/0/0
10.2.1.2/32 Direct 0 0 D 10.2.1.2 GigabitEthernet1/0/0
10.2.1.1/32 Direct 0 0 D 127.0.0.1 InLoopBack0
127.0.0.0/8 Direct 0 0 D 127.0.0.1 InLoopBack0
127.0.0.1/32 Direct 0 0 D 127.0.0.1 InLoopBack0
200.1.1.0/24 Direct 0 0 D 200.1.1.1 GigabitEthernet2/0/0
200.1.1.1/32 Direct 0 0 D 127.0.0.1 InLoopBack0
Run the display ip routing-table vpn-instance command on PE. It shows that there are routes
to the VPN site of the remote CE in the VPN instances of the PE.
Consider PE2 as an example:
[PE2] display ip routing-table vpn-instance vpn1
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Routing Tables: vpn1
Destinations : 8 Routes : 8
Destination/Mask Proto Pre Cost Flags NextHop Interface
Huawei AR1200 Series Enterprise Routers
Configuration Guide - VPN 3 BGP MPLS IP VPN Configuration
Issue 01 (2012-04-20) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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