Configuring the Inter-AS VPN Option A

Context

When inter-AS VPN Option A is used, ASBRs must support the VPN instance IPv6 address family and manage VPN-IPv6 routes. In addition, the ASBRs must provide dedicated interfaces for each inter-AS IPv6 VPN network. Option A poses high requirements on ASBRs; however, for inter-AS networking, ASBRs do not need any special configurations.

Procedure

To implement inter-AS VPN Option A, complete basic BGP/MPLS IPv6 VPN configuration in each AS and configure the peer ASBR-PEs as the CE of each other. You need to configure VPN instances for a PE and an ASBR-PE respectively. The PE connects to CEs, and the ASBR-PE connects to the remote ASBR-PE. For details about basic BGP/MPLS IPv6 VPN configuration, see Configuring Basic BGP/MPLS IPv6 VPN.

In inter-AS IPv6 VPN Option A, the VPN targets of the VPN instances having the IPv6 address family enabled on the ASBRs and PEs in an AS must match; the VPN targets of the VPN instances having the IPv6 address family on PEs in different ASs do not need to match.

Verifying the Configuration

After inter-AS IPv6 VPN Option A is configured, run the following commands to verify the configuration.

Run the display bgp vpnv6 all peer command on the PE or ASBR. If a BGP VPNv6 peer relationship is established between the PE and ASBR in the same AS and in Established state, the configuration is successful.
Run the display bgp vpnv6 all routing-table command on a PE or ASBR to check the VPNv6 routes.
Run the display ipv6 routing-table vpn-instance vpn-instance-name command on a PE or ASBR. If the VPN routing table of the PE or ASBR has all related VPN routes, the configuration is successful.