Enabling multipathing

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To use multipathing in SnapDrive for UNIX, you must complete steps that include installing and starting the HBA. If you are using a non-NetApp multipathing solution, you must download the software and application package from the HBA vendor’s web site.

Your system must be running current versions of FC and iSCSI system components.

Steps
  1. Install the supported HBAs before you install the appropriate Host Utilities software.

    SnapDrive for UNIX supports multivendor HBAs.
  2. Start the HBA service.

    If the HBA service is not running, the following error message is displayed when you run SnapDrive for UNIX commands, such as snapdrive storage create and snapdrive config prepare luns:

    0001-876 Admin error: HBA assistant not found

    You must verify that the required number of paths are up and running. You can verify the paths by using the sanlun utility, which is included with the Host Utilities software. For example, in the FC multipathing configuration, you can use the sanlun fcp show adapter -v command.

    In the following example, there are two HBA ports (fcd0 and fcd1) connected to the host that are operational (port state). You can have only one HBA or iSCSI initiator and you must configure multipathing by providing more than one path to the target LUNs.

    # sanlun fcp show adapter -v
    adapter name: fcd0
    WWPN: 50060b000038c428
    WWNN: 50060b000038c429
    driver name: fcd
    model: A6826A
    model description: Fibre Channel Mass Storage Adapter
    (PCI/PCI-X)
    serial number: Not Available
    hardware version: 3
    driver version: @(#) libfcd.a HP Fibre Channel
    ISP 23xx & 24xx Driver B.11.23.04
    /ux/core/isu/FCD/kern/src/common/wsio/fcd_init.c:Oct 18
    2005,08:19:50
    firmware version: 3.3.18
    Number of ports: 1 of 2
    port type: Fabric
    port state: Operational
    supported speed: 2 GBit/sec
    negotiated speed: 2 GBit/sec
    OS device name: /dev/fcd0
    adapter name: fcd1
    WWPN: 50060b000038c42a
    WWNN: 50060b000038c42b
    driver name: fcd
    model: A6826A
    model description: Fibre Channel Mass Storage Adapter
    (PCI/PCI-X)
    serial number: Not Available
    hardware version: 3
    driver version: @(#) libfcd.a HP Fibre Channel
    ISP 23xx & 24xx Driver B.11.23.04
    /ux/core/isu/FCD/kern/src/common/wsio/fcd_init.c:Oct 18
    2005,08:19:50
    firmware version: 3.3.18
    Number of ports: 2 of 2 port type: Fabric
    port state: Operational
    supported speed: 2 GBit/sec
    negotiated speed: 2 GBit/sec
    OS device name: /dev/fcd1

    If multipathing is enabled on a host, multiple paths are visible for the same LUN. You can use the sanlun lun show all command to verify the paths. In the following example, you can find multiple paths to the same LUN (fish: /vol/vol1/lun):

    filer:         lun-pathname        device filename  adapter    protocol   lun size              lun state
        filer_1:        fish/vol/vol1/l1      hdisk36          fcs0       FCP       5m   (5242880)        GOOD
        filer_2:        fish/vol/vol0/lunKr   hdisk39          fcs0       FCP       100m (104857600)      GOOD
        filer_3:        fish/vol/vol0/testaix hdisk2           fcs0       FCP       200m (209715200)      GOOD
        filer_4:        fish/vol/vol1/l1      hdisk45          fcs1       FCP       5m   (5242880)        GOOD
  3. In an FC configuration, zone the host HBA ports and target ports by using the switch zoning configuration.

  4. Install and set up the appropriate FC or iSCSI switch.

  5. Check the SnapDrive for UNIX stack requirements.

  6. Install or upgrade SnapDrive for UNIX.

  7. Verify the SnapDrive for UNIX installation.

  8. Locate the snapdrive.conf file path.

  9. Configure the following configuration variables in the snapdrive.conf file:

    • multipathing-type

    • default-transport

    • fstype

    • vmtype

      For every host, the multipathing type, transport type, file system, and volume manager type are dependent on each other. The following table describes all the possible combinations:

    Host platform Default transport type Multipathing type fstype vmtype

    AIX

    FCP

    absolute

    jfs2 or jfs

    lvm

    nativempio

    jfs2 or jfs

    lvm

    dmp

    vxfs

    vxvm

    The preceding table gives the supported values of the multipathing-type, default-transport, fstype, and vmtype configuration variables.

  10. Save the snapdrive.conf file.

    SnapDrive for UNIX automatically checks this file each time it starts. You must restart the SnapDrive for UNIX daemon for the changes to take effect.

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