To be able to use the RDMA capable adapter for iSCSI, use the esxcli to enable the VMware iSER storage component. After you enable the component, it appears in the vSphere Client as a vmhba# storage adapter under the VMware iSCSI over RDMA (iSER) Adapter category.

Prerequisites

  • Make sure that your iSCSI storage supports the iSER protocol.
  • Install the RDMA capable adapter on your ESXi host. For information, see Install and View an RDMA Capable Network Adapter.
  • For RDMA capable adapters that support RDMA over Converged Ethernet (RoCE), determine the RoCE version that the adapter uses.
  • Use the RDMA capable switch.
  • Enable flow control on the ESXi host. To enable flow control for the host, use the esxcli system module parameters command. For details, see the VMware knowledge base article at http://kb.vmware.com/kb/1013413.
  • Make sure to configure RDMA switch ports to create lossless connections between the iSER initiator and target.

Procedure

  1. Use the ESXi Shell or vSphere CLI to enable the VMware iSER storage adapter and set its RoCE version.
    1. Enable the iSER storage adapter.
      esxcli rdma iser add
    2. Verify that the iSER adapter has been added.
      esxcli iscsi adapter list
      The output is similar to the following. 
      Adapter Driver State UID Description
------- ------ ------- ------------- -------------------------------------
vmhba64 iser unbound iscsi.vmhba64 VMware iSCSI over RDMA (iSER) Adapter
    3. Specify the RoCE version that iSER uses to connect to the target.
      Use the RoCE version of the RDMA capable adapter. The command you enter is similar to the following:

      esxcli rdma iser params set -a vmhba64 -r 1

      When the command completes, a message similar to the following appears in the VMkernel log.

      vmkernel.0:2020-02-18T18:26:15.949Z cpu6:2100717 opID=45abe37e)iser: iser_set_roce: Setting roce type: 1 for vmhba: vmhba64
vmkernel.0:2020-02-18T18:26:15.949Z cpu6:2100717 opID=45abe37e)iser: iser_set_roce: Setting rdma port: 3260 for vmhba: vmhba64

      If you do not specify the RoCE version, the host defaults to the highest RoCE version the RDMA capable adapter supports.

  2. Use the vSphere Client to display the iSER adapter.
    1. In the vSphere Client, navigate to the ESXi host.
    2. Click the Configure tab.
    3. Under Storage, click Storage Adapters, and review the list of adapters.
      If you enabled the adapter, it appears as a storage vmhba# adapter on the list under the VMware iSCSI over RDMA (iSER) Adapter category.

      The screenshot shows a list of storage adapters and vmhba64 that appears on the list under the VMware iSCSI over RDMA (iSER) Adapter category.

  3. Select the iSER storage vmhba# to review its properties or perform the following tasks.
    Option Description
    Configure port binding for the iSER storage adapter You must create network connections to bind the iSER storage adapter vmhba# and the RDMA capable network adapter vmnic#. The process of configuring these connections is called port binding. For general information about port binding, see Setting Up Network for iSCSI and iSER. To configure port binding for iSER, see Configure Port Binding for iSCSI or iSER.
    Set up dynamic or static discovery for the iSER storage adapter For information, see Configure Dynamic or Static Discovery for iSCSI and iSER on ESXi Host.
    Configure the Challenge Handshake Authentication Protocol (CHAP) for the iSER storage adapter For information, see Set Up CHAP for iSCSI or iSER Storage Adapter.

What to do next

For more information, see the VMware knowledge base article at https://kb.vmware.com/s/article/79148.