227
To do…
Use the command…
Remarks
Make BGP updates to be sent carry
no private AS numbers
peer
{
group-name
|
ip-address
}
public-as-only
Optional
By default, a BGP update carries
private AS numbers.
Apply a routing policy to a peer or
peer group
peer
{
group-name
|
ip-address
}
route-policy
route-policy-name
{
export
|
import
}
Optional
By default, no routing policy is
applied to a peer or peer group.
NOTE:
For information about BGP routing, see
Layer 3—IP Routing Configuration Guide.
Configuring inter-AS VPN
If the MPLS backbone on which the VPN routes rely spans multiple ASs, you must configure inter-AS VPN.
There are three inter-AS VPN solutions. You can choose them as required.
Configuration prerequisites
Before configuring multi-provider VPN, complete the following tasks:
•
Configure an IGP for the MPLS backbones in each AS to implement IP connectivity of the backbones
in the AS
•
Configure basic MPLS capabilities for the MPLS backbones of each AS
•
Configure MPLS LDP for the MPLS backbones so that LDP LSPs can be established
•
Configure basic MPLS L3VPN for each AS
NOTE:
When configuring basic MPLS L3VPN for each AS, specific configurations may be required on PEs or
ASBR-PEs. This depends on the inter-AS VPN solution selected.
Configuring inter-AS option A
Inter-AS option A applies to scenarios where the number of VPNs and that of VPN routes on the PEs are
relatively small. It is simple to implement.
To configure inter-AS option A, you only need to do the following:
•
Configure basic MPLS L3VPN on each AS.
•
Configure each ASBR, taking the peer ASBR PE as its CE.
In other words, configure VPN instances for PEs and ASBR PEs respectively. The VPN instance for PE is
used to allow CEs to access the network, while that for ASBR-PE is used to access its peer ASBR-PE.
For more information, see “
.”
