Abstract: In one embodiment, an intermediate node includes one or more active forwarding planes and one or more redundant forwarding planes. The intermediate node may also include one or more active control planes and one or more redundant control planes. A test packet is generated, in some cases by a redundant control plane, and transferred to a redundant forwarding plane. The operational state of the redundant forwarding plane is verified, at least in part, by using operational software and hardware contained in the redundant forwarding plane to forward the test packet from the redundant forwarding plane to a target line card. The target line card loops the test packet back to the redundant forwarding plane as part of the verification process. In some cases, the redundant control plane processes the looped-back test packet.

Abstract: A technique for verifying an intermediate node that employs a forwarding plane and optionally a control plane. A test packet is generated and transferred to the forwarding plane. Using operational software and hardware, the forwarding plane forwards the test packet to a line card, which in turn “loops” the test packet back to the forwarding plane. Using operational software and hardware, the forwarding plane processes the looped-back test packet including forwarding the packet to a destination, such as a control plane, where the looped-back test packet is verified.