258
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:
•
Configure basic MPLS L3VPN on each AS.
•
Configure each ASBR-PE, taking the peer ASBR-PE as its CE.
In other words, configure VPN instances on PEs and ASBR PEs respectively. The VPN instances on PEs are
used to allow CEs to access the network, and those on ASBR PEs are used to access the peer ASBR PEs.
For more information, see “
.”
NOTE:
In the inter-AS option A solution, for the same VPN, the VPN targets configured on the PEs must match
those configured on the ASBR-PEs in the same AS to make sure that VPN routes sent by the PEs (or
ASBR-PEs) can be received by the ASBR-PEs (or PEs). VPN targets configured on the PEs in different ASs
do not have such requirements.
Configuring inter-AS option B
To configure inter-AS option B on ASBR PEs:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter interface view for the
interface connecting to the
remote ASBR-PE.
interface
interface-type
interface-number
N/A
3.
Configure the IP address of
the interface.
ip address
ip-address
{
mask
|
mask-length
}
N/A
4.
Return to system view.
quit
N/A
5.
Enter BGP view.
bgp
as-number
N/A
6.
Enter BGP-VPNv4 subaddress
family view.
ipv4-family vpnv4
N/A
7.
Disable VPN target filtering
for VPNv4 routes.
undo policy vpn-target
By default, PE performs VPN target
filtering of the received VPNv4
routes.
The routes surviving the filtering
will be added to the routing table,
and the others are discarded.