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Mellanox What Just Happened (WJH)

Cumulus Linux supports the What Just Happened (WJH) feature for Mellanox switches to stream detailed and contextual telemetry for off-box analysis with tools, such as NVIDIA NetQ. This advanced streaming telemetry technology provides real time visibility into problems in the network, such as hardware packet drops due to buffer congestion, incorrect routing, ACL or layer 1 problems.

When WJH capabilities are combined with the analytics engine of NVIDIA NetQ, you have the ability to hone in on any loss, anywhere in the fabric, from a single management console. You can view any current or historic drops and specific drop reasons, and also identify any flow or endpoints and pin-point exactly where communication is failing in the network.

WJH is enabled by default on a Mellanox switch; no configuration is required in Cumulus Linux.