A method for discovering a forwarding path, comprising: receiving, by a first device, a packet that is sent by a second device and that is used to discover a forwarding path, wherein the packet contains an operation parameter that includes a destination address of a target node of the packet and a source IP address of an ingress node that used the packet to discover the forwarding path; searching, by the first device a forwarding information base of a data plane of the first device based on the destination address in the operation packet, to obtain a first forwarding entry, to determine from the first forwarding entry, first path information used to forward the packet; and searching, by the first device, a forwarding information base of an autonomic control plane virtual routing and forwarding, ACP VRF, instance of the first device based on the ACP Unique Local Address, ULA, of the ingress node in the operation parameter to obtain a second forwarding entry corresponding to the ACP ULA of the ingress node and determine from the second forwarding entry reverse forwarding information used to send the first path information to the ingress node; and sending, by the first device, the first path information to the ingress node; wherein the first forwarding entry is included in the forwarding information base of the data plane and the second forwarding entry is included in the forwarding information base of the ACP VRF; and wherein the forwarding information base of the ACP VRF and the forwarding information base of the data plane belong to different physical forwarding information bases; or the forwarding information base of the ACP VRF and the forwarding information base of the data plane belong to a same physical forwarding information base but are logically isolated; characterised in that: when the first device cannot find the first forwarding entry, the first path information comprises information used to indicate that the path is interrupted, wherein the first path information comprises an IP address of the first device and an identifier of a port used by the first device to receive the packet. receiving, by a first device, a packet that is sent by a second device and that is used to discover a forwarding path, wherein the packet contains an operation parameter that includes a destination address of a target node of the packet and a source IP address of an ingress node that used the packet to discover the forwarding path; searching, by the first device a forwarding information base of a data plane of the first device based on the destination address in the operation packet, to obtain a first forwarding entry, to determine from the first forwarding entry, first path information used to forward the packet; and searching, by the first device, a forwarding information base of an autonomic control plane virtual routing and forwarding, ACP VRF, instance of the first device based on the ACP Unique Local Address, ULA, of the ingress node in the operation parameter to obtain a second forwarding entry corresponding to the ACP ULA of the ingress node and determine from the second forwarding entry reverse forwarding information used to send the first path information to the ingress node; and sending, by the first device, the first path information to the ingress node; wherein the first forwarding entry is included in the forwarding information base of the data plane and the second forwarding entry is included in the forwarding information base of the ACP VRF; and wherein the forwarding information base of the ACP VRF and the forwarding information base of the data plane belong to different physical forwarding information bases; or the forwarding information base of the ACP VRF and the forwarding information base of the data plane belong to a same physical forwarding information base but are logically isolated; characterised in that: when the first device cannot find the first forwarding entry, the first path information comprises information used to indicate that the path is interrupted, wherein the first path information comprises an IP address of the first device and an identifier of a port used by the first device to receive the packet.