Multi-Path setup for Linux

Multipathing enables you to configure multiple I/O paths between server nodes and storage arrays into a single device. These I/O paths are physical SAN connections that can include separate cables, switches, and controllers.

The following instructions are provided for the administrator of the DE Series storage array to set up multi-path for Linux.

Linux NVMe over RoCE multipathing

Before you do
  • You have installed the required packages on your system.
  • For SLES 12 SP5 and later hosts, verify the packages are installed by running rpm -q multipath-tools

By default, DM-MP is disabled in RHEL and SLES. Complete the following steps to enable DM-MP components on the host.

Steps
  1. Add the NVMe DE Series device entry to the devices section of the /etc/multipath.conf file, as shown in the following example:
    
devices {
        device {
                vendor "NVME"
                product "Lenovo DE-Series"
                path_grouping_policy group_by_prio
                failback immediate
                no_path_retry 30
        }
}
  2. Configure multipathd to start at system boot.
    # systemctl enable multipathd
  3. Start multipathd if it is not currently running.
    # systemctl start multipathd
  4. Verify the status of multipathd to make sure it is active and running:
    # systemctl status multipathd

Linux NVMe over Fibre Channel multipathing

DE Series SAN OS 11.60.2 uses native settings for Linux NVMe over Fiber Channel multipathing; no additional modification is required.

Note: Asynchronous and synchronous mirroring are not supported for NVMe over Fabrics. If you have either mirroring feature installed, this will result in out_of_compliance messages in the Recovery Guru. Refer to the Disable storage array feature mirroring commands under the ThinkSystem System Manager online help or Command Line Interface (CLI) Reference for more information on how to disable mirroring.
Parent topic: Linux express configuration