Hi,
As we see in the Mellanox Webpage, ConnectX2 devices doesn't support RoCE V2, see http://www.mellanox.com/page/products_dyn?product_family=79&mtag=roce
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The Mellanox NICs with its hardware offload support takes advantage of this efficient RDMA transport (InfiniBand) services over Ethernet to deliver ultra-low latency for performance-critical and transaction intensive applications such as financial, data base, storage, and content delivery networks.
Mellanox adapter cards (ConnectX-3 Pro and onward) support RoCE which allows RDMA to be used across both L2 and L3 networks thanks to IP and UDP headers.
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