Dell VxRail Network Planning Guide

VxRail RoCE adapter options

The RoCE adapter supports RDMA connectivity over converged networks. RDMA technology sends data over a network without involving the CPU in the transfer.

Enabling RDMA over converged Ethernet network infrastructure provides faster data transfer for network-intensive applications through lower I-O latencies. IOPS performance is improved in comparison to other network-based storage connectivity options. The port speed for the Mellanox adapter is 25 GbE.

The following guidelines apply for RoCE-supported adapters:

• Configure all cluster nodes that are connected to the common VMware vSAN data store with RoCE-supported adapter cards from the same vendor with the same model. Variations in adapters from different vendors or different models can disrupt I/O on the VMware vSAN data store.
• The Ethernet ports on the RoCE-supported adapters are reserved for VMware vSAN traffic only.
• The physical network supporting VMware vSAN is configured as a lossless network. To determine which Ethernet adapters support RDMA, see the appropriate VxRail Support Matrix on the Dell Support site.