nd vlink-direct-route advertise

Usage Scenario

IP packets are forwarded based on a specified physical interface, but cannot be forwarded based on a VLANIF interface because a VLANIF interface is a logical interface with several physical interfaces as its member interfaces. If a packet reaches a VLANIF interface, the device needs to obtain information about the physical interfaces using NDP and generates relevant routing entries with physical interfaces specified. The routes recorded by the routing entries are called NDP Vlink direct routes.

In a VPN, a local PE connects to multiple CEs using VLANIF interfaces. Based on NDP, the local PE learns IP addresses of these CEs and generates NDP Vlink direct routes. In most cases, NDP Vlink direct routes are used only to guide local traffic forwarding and are not advertised. In this manner, the scale and stability of the routing table can be controlled.

If NDP Vlink direct routes to a few CEs have to be advertised, you can configure the nd vlink-direct-route advertise command, with the parameter route-policy route-policy-name specified. This configuration ensures that only filtered NDP Vlink direct routes are advertised, the scale of the routing table is controlled, and the security of VLAN users is guaranteed.

Configuration Impact

After the parameter route-policy route-policy-name is specified in the nd vlink-direct-route advertise command, only filtered NDP Vlink direct routes are advertised.

Follow-up Procedure

Advertised NDP Vlink direct routes also need to be imported to the routing table of each dynamic routing protocol on the router. In this manner, the NDP Vlink direct routes can be advertised by each dynamic routing protocol module.

Precautions

The parameter route-policy route-policy-name must be specified in the nd vlink-direct-route advertise command. If the parameter is not specified, NDP Vlink direct routes cannot be filtered.