ECN: Per-queue accounting of ECN packets

You can track explicit congestion notification (ECN)-marked traffic with ECN-CE packet and byte counters in queue statistics and telemetry, helping you monitor congestion and validate ECN behavior.

Enable support by setting [class-of-service options hierarchical-scheduler-disable] and then reboot to operate in Non-HCoS mode. Use [show interfaces queue interface-name forwarding-class forwarding-class-name] to export ecn-marked-pkts and ecn-marked-octets via telemetry.

ECN counter statistics export is not supported in the interoperability mode, where Express 4 and Express 5 line cards are used in the same PTX10K chassis. In Non-HCoS mode, the default multicast queue is unshaped and can starve unicast traffic.