Arista Networks, Inc.
REPROGRAMMING MULTICAST REPLICATION USING REAL-TIME BUFFER FEEDBACK

Abstract:

Methods and systems are described for programming a substitution of ingress replication buffering for egress replication buffering after identifying egress buffer errors (such as overflow) for multicast traffic. A network element is configured to identify which ports drop packets by monitoring egress buffers and/or multicast traffic in real time. A hardware forwarding engine provides feedback to a control plane processor of the network element to adapt and selectively reprogram multicast ingress replication, temporarily, for certain egress ports that may have, e.g., egress buffer errors or risk of issues due to high network traffic. Using virtual output queues in ingress buffers may reduce risk of egress port congestion, as egress buffers have more limited resources than ingress buffers; however, relying solely on ingress replication for multicast traffic may hinder unicast traffic. Ingress buffer replication of multicast traffic may be used selectively and temporarily.