RoCEv2 traffic must be mapped to a no-drop QoS class when lossless Ethernet operation is required. Cisco's current Intersight VIC configuration guidance provides an explicit configuration for this requirement: create a System QoS policy, select Platinum as the priority, and clear the Allow Packet Drops checkbox. The policy is then associated with the UCS Domain Profile.

Cisco's storage best-practice documentation gives the same configuration for NVMe over RoCEv2: Platinum enabled, Allow Packet Drops unchecked, and a jumbo MTU—commonly 9216 at the system-class level. This establishes the UCS-side no-drop class required for RDMA traffic.

Disabling Platinum, as proposed in option A, would remove the intended lossless traffic class. Enabling every system class in option B does not automatically make RoCEv2 lossless because packet-drop behavior remains a property of the selected class. Disabling Gold in option C is unrelated to ensuring that the RoCE traffic class receives no-drop treatment.

A complete RoCE design must maintain consistent QoS classification and no-drop handling end to end. However, for the System QoS policy requested here, option D is the precise Cisco configuration.

Study Guide Reference: AI Infrastructure Deployment and Data Management — RoCEv2, PFC, lossless Ethernet, and UCS System QoS.

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