Learn how to install a remote direct memory access (RDMA) network adapter on your ESXi hosts. Once installed, you can use the vSphere Client to view the RDMA adapter and its corresponding network adapter, and configure its VMkernel binding.

RDMA provides direct memory access from the memory of one host to the memory of another host without involving the remote operating system and CPU. This boosts network and host performance with lower latency, lower CPU load, and faster bandwidth.

Prerequisites

Install an RDMA-capable adapter on your ESXi host. For example, Mellanox Technologies MT27700 Family ConnectX-4.

View RDMA Capable Network Adapter

ESXi supports RDMA capable network adapters. After you install such an adapter on your ESXi host, the vSphere Client displays its two components, the RDMA adapter, and a physical network adapter.

You can use the vSphere Client to view the RDMA adapter and its corresponding network adapter.

Prerequisites

Install a RDMA-capable adapter that supports RDMA (RoCE v2) on your ESXi host. For example, Mellanox Technologies MT27700 Family ConnectX-4.

Procedure

  1. On your ESXi host, install a RDMA-capable adapter that supports RDMA (RoCE v2).
    The host discovers the adapter and the vSphere Client displays its two components, an RDMA adapter, and a physical network adapter.
  2. Navigate to the host.
  3. Under Networking, click RDMA adapters.
    In this example, the RDMA adapter appears on the list as vmrdma0. The Paired Uplink column displays the network component as the vmnic1 physical network adapter.
    Figure 1. RDMA adapters installed on an ESXi host in a vSphere environment.

    RDMA adapters installed on an ESXi host in a vSphere environment.
  4. To verify the description of the adapter, select the RDMA adapter from the list, and click the Properties tab.

Configure Remote Direct Memory Access Network Adapters

You can install a remote direct memory access (RDMA) network adapter and configure its VMkernel binding.

Procedure

  1. Install an RDMA-capable adapter that supports RDMA (RoCE v2) on your ESXi host.
    The host discovers the adapter and the vSphere Client displays its two components, an RDMA adapter and a physical network adapter.
  2. In the vSphere Client, verify that the RDMA adapter is discovered by your host.
    1. Navigate to the host.
    2. Click the Configure tab.
    3. Under Networking, click RDMA adapters.
      In this example, the RDMA adapter appears on the list as vmrdma0. The Paired Uplink column displays the network component as the vmnic1 physical network adapter.

      RDMA adapter is paired to the network adapter and is connected to the physical network adapter.

    4. To verify the description of the adapter, select the RDMA adapter from the list, and click the Properties tab.
  3. Configure VMkernel binding for the RDMA adapter.
    In the configuration, you can use a vSphere standard switch or a vSphere Distributed Switch. The following steps use the standard switch as an example.
    1. Create a vSphere standard switch and add the network component to the switch.
      Note: Make sure to select the physical network adapter that corresponds to the RDMA adapter. In this example, it is the vmnic1 adapter.

      For information about creating the switch, see Create a vSphere Standard Switch or Create a vSphere Distributed Switch.

    2. Add a VMkernel adapter to the vSphere standard switch that you created.
      Assign an appropriate static IPv4 or IPv6 address to the VMkernel adapter, so that your RDMA adapter can discover the NVMe over RDMA target.

      For information about adding the VMkernel adapter, see How do I Set Up VMkernel Networking.

    The illustration shows that the physical network adapter and the VMkernel adapter are connected to the vSphere standard switch. Through this connection, the RDMA adapter is bound to the VMkernel adapter.

    The physical network adapter and the VMkernel adapter are connected to the vSphere Standard Switch. RDMA adapter is bound to the VMkernel adapter.

  4. Verify the VMkernel binding configuration for the RDMA adapter.
    1. Navigate to the RDMA adapter.
    2. Click the VMkernel adapters binding tab and verify that the associated VMkernel adapter appears on the page.
      In this example, the vmrdma0 RDMA adapter is paired to the vmnic1 network adapter and is connected to the vmk1 VMkernel adapter.

      RDMA adapter is paired to the network adapter and is connected to the VMkernel adapter.

What to do next

You can use the RDMA network component of the adapter for such storage configurations as iSER or NVMe over RDMA. To learn more, see the vSphere Storage documentation.