Planning for 25 Gbps Ethernet adapters

The system supports 25 Gbps Ethernet adapters that provide both iSCSI and iSCSI Extensions over RDMA (iSER) connections. Review prerequisite system requirements and installation considerations before deployment.

It is helpful to be familiar with the following terms when you are considering the features of the 25 Gbps Ethernet adapter for these connections.
Remote Direct Memory Access (RDMA)
RDMA is an networking standard that allows the adapters to transfer data directly to or from the endpoints in a connection without using CPU resources on either of the endpoints. These transfers occur in simultaneously with other system operations and do not impact overall system performance. When system performs an I/O operation over an RDMA-based connection, data is sent directly to the network, which reduces latency and increases the speed of data transfers.
iSCSI Extensions for RDMA (iSER)
iSER is a network protocol that extends the iSCSI protocol to use RDMA. You can implement RDMA-based connections that use existing Ethernet networking structures and connections without upgrading current hardware. Currently the system supports RDMA-based connections with RDMA over Converged Ethernet (RoCE) or Internet Wide Area RDMA Protocol (iWARP). If you are undecided whether to use RoCE or iWARP in your data center, search the internet for iSCSI Extensions for RDMA to obtain more information.
Review the following elements when you are deciding to install the optional 25 Gbps adapter: