3com S7906E Installation Instruction

 

1-40 

Enable nested VPN 

Required 

Disabled by default. 

Activate a nested VPN peer or 
peer group, and enable the 
BGP-VPNv4 route exchange 
capability 

peer { group-name | 
peer-address } vpn-instance 
vpn-instance-name enable 

Required 

By default, only IPv4 routes and 
no BGP-VPNv4 routes can be 
exchanged between nested 
VPN peers/peer groups. 

Add a peer to the nested VPN 
peer group 

peer peer-address 
vpn-instance 
vpn-instance-name group 
group-name 

Optional 

By default, a peer is not in any 
nested VPN peer group. 

Specify to apply a routing policy 
to routes received from a 
nested VPN peer or peer group 

peer { group-name | 
peer-address } vpn-instance 
vpn-instance-name 
route-policy 
route-policy-name import 

Optional 

By default, no routing policy is 
applied to routes received from 
a nested VPN peer or peer 
group. 

 

z 

The address ranges for sub-VPNs of a user VPN cannot overlap. 

z 

It is not recommended to give nested VPN peers addresses that public network peers use. 

z 

Before specifying a nested VPN peer or peer group, be sure to configure the corresponding CE 

peer or peer group in BGP VPN instance view. 

z 

At present, nested VPN does not support multi-hop EBGP networking. Therefore, a service 

provider PE and its peer must use the addresses of the directly connected interfaces to establish 

neighbor relationship. 

z 

If a CE of a sub-VPN is directly connected to a service provider’s PE, policy routing must be 

configured on the PE to allow mutual access between the sub-VPN and the VPN on the backbone. 

 

For hierarchical VPNs, you can adopt HoVPN to reduce the performance requirements for PEs. 

Before configuring HoVPN, complete these tasks: 

z 

Configuring basic MPLS L3VPN 

Follow these steps to configure HoVPN: 

Enter system view 

— 

Enter BGP view 

bgp as-number 

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