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6 Dell EMC Networking – RDMA over Converged Ethernet (RoCE v2) Cheat Sheet
Dell EMC Networking RoCE v2 Reference Environment.
To demonstrate how Dell EMC networking ensures quality of service in a converged
environment, congestion is created on the links between the leaf and spine (port-channels
10 & 20). A port-channel sized at 20GbE is configured between the leaf and spine
interlinks.
Through the use of an IXIA traffic generator, LAN and iSCSI traffic are simulated. LAN
traffic is running at 40Gbps, and iSCSCI is running at 10Gbps congesting the inter-links
between the leaf and spine switches. RDMA traffic is then added to this congested set of
links, through the use of simulated RDMA traffic between the servers using SMB 3.0 (fully
integrated into Windows 2016 Server) in conjunction with ImDisk and IOmeter.
2.1 Spine Layer – (S4148Fs-ON)
The spine layer consists of two S4128Fs terminating all Layer 2 and Layer 3 traffic. Dell
EMC’s Virtual Link Trunk (VLT) is deployed creating a virtual switch at the spine layer. The
connections between the spine and leaf are purposely congested to demonstrate end-to-
end lossless connectivity for RoCE v1 data traffic.
2.2 Leaf Layer – (S4048-ON-3, S4048-ON-4)
At the leaf layer, two S4048s are running OS9 and OS10. The setup shows how an OS9
based system integrates well with the newer OS10 system.
The Leaf switches act as ToR (Top of Rack) switches providing end device connectivity to
the fabric.