A first network device includes a processor and a memory having instructions stored thereon that, when executed by the processor, cause the first network device to: obtain a first virtual private network (VPN) route sent by a second network device. The first VPN route includes first identification information that uniquely identifies a first VPN instance in the second network device. The first network device is also caused to generate a second VPN route according to a second VPN instance accessing a third network device and the first VPN route. The second VPN route carries second identification information and routing information of the first VPN route. The second identification information uniquely identifies the second VPN instance in the third network device. The first identification information is different from the second identification information. The first network device is further caused to send the second VPN route to the third network device.