Configuring Bgp As Number Substitution; Configuration Prerequisites; Configuration Procedure - 3Com MSR 50 Series Configuration Manual

1498 C 79: MPLS L3VPN C
HAPTER
Configuration
Prerequisites

Configuration Procedure

Configuring BGP AS
Number Substitution
Configuration
Prerequisites
Configuration Procedure
ONFIGURATION
Before configuring multi-VPN-instance CE, complete these tasks:
Configuring VPN instances
■
Configuring the link layer and network layer protocols on related interfaces to
■
ensure IP connectivity.
Multi-VPN-instance CE can be regarded as a networking solution for
implementing service isolation by route isolation. There is no special configuration
required for a multi-VPN-instance CE, except that you need to enable the
multi-VPN-instance CE function.
After you enable multi-VPN-instance CE, routing loop detection on the PE is
disabled for route calculating routes to avoid route loss, and BGP/OSPF
interoperability is disabled to save system resources.
Follow these steps to configure multi-VPN-instance CE:
To do...
Enter system view
Enter OSPF multi-instance
view
Enable multi-VPN-instance CE vpn-instance-capability simple
Before configuring BGP AS number substitution, complete these tasks:
Configuring basic MPLS L3VPN
■
Configuring CEs at different sites to have the same AS number
■
When CEs at different sites have the same AS number, you need to configure the
BGP AS number substitution function to avoid route loss.
With the BGP AS number substitution function, when a PE advertises a route to a
CE of the specified peer, if an AS number identical to that of the CE exist in the
AS_PATH of the route, it will be replaced with that of the PE before the route is
advertised.
Follow these steps to configure the BGP AS number substitution function:
To do...
Enter system view
Enter BGP view
Enter BGP VPN instance view
Use the command...
system-view
ospf [ process-id | router-id
router-id | vpn-instance
vpn-instance-name ] *
Use the command...
system-view
bgp as-number
ipv4-family vpn-instance
vpn-instance-name
Remarks
-
-
Required
Disabled by default
Remarks
-
Required
Required