Talk:QoS Design Considerations for Virtual UC with UCS
In 4.1 Standard Switching Element QoS Behavior, it is stated that CoS3 is not exclusive for Fibre Channel traffic and can be used by voice signaling traffic, that when voice signaling traffic is marked CoS3 by Nexus1000v, it will be in the same queue as Fibre Channel traffic. However according to CSCuj73360, CoS3 is not shared with other traffic but is only for Fibre Channel traffic. When signaling traffic marked as CoS3 by N1kv enters FI, it is automatically remarked as CoS0 even though the vNIC is configured as FULL. It seems to be a day one behavior. If this is the case than we have an issue, as UC best practice has been to mark signaling with CoS3, then this behavior breaks that. Also this design guide is incorrect, and systems built based on this guide have the risk of losing signaling during congestion on switched network since signaling is treated as best effort traffic.