Communicating network path and status information in multi-homed networks

摘要

An example network system includes a layer two (L2) device and a layer three (L3) device. The L2 device includes a control unit is configured to determine a preferred network path from a first L2 network in which the L2 device resides to an intermediate L3 network in which the L3 device resides that couples the first L2 network to a second L2 network having a second L2 device. The control unit includes a management endpoint (MEP) module. The MEP module executes an operations, administration, and management (OAM) protocol to monitor the first L2 network and output an L2 frame in accordance with the OAM protocol to the L3 device to notify the L3 device that it is within the preferred network path. A MEP module of the L3 device executes an OAM protocol that outputs L2 frames to the L2 device indicating the status of the L3 network.

主权项

1. A method comprising:
learning, with a layer two (L2) device, a set of remote media access control (MAC) addresses reachable over a network link connecting the L2 device to a layer three (L3) device; storing, with the L2 device, the learned set of remote MAC addresses within the L2 device; receiving, with the L2 device and from the L3 device, an L2 frame issued by an operations, administration, and management (OAM) protocol executing on the L3 device, wherein the L2 frame carries a first type-length-value (TLV) field that indicates a portion of the learned set of MAC addresses to remove and directs the L2 device to remove the portion of the learned set of MAC addresses from the learned set of MAC addresses stored within the L2 device and a second TLV field that indicates a network error, wherein the portion of the learned set of MAC addresses include MAC addresses impacted by the network error, and wherein the L2 frame is a continuity check message used by the OAM protocol executing on the L3 device to detect connectivity failures between a sending device and a destination device; and in response to receiving the L2 frame from the L3 device, removing, with the L2 device, the portion of the learned set of MAC addresses indicated by the L2 frame from the learned set of MAC addresses stored within the L2 device.