This application provides a data traffic processing method, a device, and a system. The method includes: receiving, by a first network device on a first link, a first VXLAN packet sent by a second network device, where the first VXLAN packet includes a first sequence number and a first service packet; decapsulating, by the first network device, the first VXLAN packet; receiving, by the first network device on a second link, a second VXLAN packet sent by the second network device, where the second VXLAN packet includes a second sequence number and a second service packet; and when the first network device determines that the second sequence number is a next sequence number of the first sequence number, decapsulating, by the first network device, the second VXLAN packet.