Dynamic Multi-Pathing 8.0.1 Administrator's Guide - Windows

Last Published:
Product(s): InfoScale & Storage Foundation (8.0.1)
Platform: Windows
  1. Understanding DMPW
    1.  
      DMP overview
    2.  
      Major features of Dynamic Multi-Pathing
    3. How DMP works
      1. How DMP monitors I/O on paths
        1.  
          Path failover mechanism
      2.  
        Load balancing
      3.  
        DMP in a clustered environment
    4.  
      Multiple paths to disk arrays
    5.  
      Device discovery
  2. Setting up DMPW
    1.  
      Active/Active and Active/Passive settings
    2. Active/Active and Active/Passive settings in a cluster environment
      1.  
        DMP DSMs
      2.  
        SCSI-3 PGR technology
      3.  
        Enabling SCSI-3 PGR
    3. Add and remove paths
      1.  
        Adding a path
      2.  
        Removing a path
    4. Specify load balancing settings and the primary path
      1.  
        Specifying load balancing settings for an array
      2.  
        Specifying load balancing settings for a disk
      3.  
        Specifying the primary path for an array or disk
    5. Configuring DSMs without storage connection
      1.  
        Specify DSM settings without storage connection
  3. Administering DMPW
    1.  
      About administering DMP
    2. DMP DSMs menus
      1.  
        Displaying the menu for arrays
      2.  
        Commands for arrays
      3.  
        Displaying the menu for disks
      4.  
        Commands for paths of a disk
      5.  
        Statistics monitoring
      6.  
        Clear performance statistics
      7.  
        Device settings
      8.  
        Set primary path
      9.  
        Properties
    3. View array, disk, and path status
      1.  
        Array status
      2.  
        Device status
      3.  
        Path status
    4. vxdmpadm
      1.  
        vxdmpadm dsminfo
      2.  
        vxdmpadm arrayinfo
      3.  
        vxdmpadm deviceinfo
      4.  
        vxdmpadm pathinfo
      5.  
        vxdmpadm arrayperf
      6.  
        vxdmpadm deviceperf
      7.  
        vxdmpadm pathperf
      8.  
        vxdmpadm allperf
      9.  
        vxdmpadm iostat
      10.  
        vxdmpadm cleardeviceperf
      11.  
        vxdmpadm cleararrayperf
      12.  
        vxdmpadm clearallperf
      13.  
        vxdmpadm setdsmscsi3
      14.  
        vxdmpadm setarrayscsi3
      15.  
        vxdmpadm setattr dsm
      16.  
        vxdmpadm setattr array
      17.  
        vxdmpadm setattr device
      18.  
        vxdmpadm setattr path
      19.  
        vxdmpadm set isislog
      20.  
        vxdmpadm rescan
      21.  
        vxdmpadm disk list
      22.  
        vxdmpadm getdsmattrib
      23.  
        vxdmpadm getmpioparam
      24.  
        vxdmpadm setmpioparam
  4. Performance tuning
    1.  
      Specifying control timer settings for an array
  5. Troubleshooting
    1. Resolving DMP issues
      1.  
        When a DMP license is no longer valid
      2.  
        When an unknown disk group appears in a DMP environment
    2. Using status information
      1.  
        Path status
      2.  
        Path states
  6. Glossary
    1.  
      Dynamic Multi-Pathing glossary

Major features of Dynamic Multi-Pathing

The major features of Dynamic Multi-Pathing (DMP) are described in this section.

They include the following:

  • Fault tolerance

    Provides fault tolerance to a disk system by using multiple paths to each disk. If the primary path fails, either at the card level or in the cabling from the card to the disk, a secondary path is automatically used.

  • Load balancing in Active/Active configurations

    When a system is configured as Active/Active, Dynamic Multi-Pathing makes use of all the paths to a disk for the transfer of I/O to and from the disk.

  • Support for multiple paths

    With DMP DSMs, the maximum number of I/O paths you can have is 16 per array LUN.

  • Dynamic recovery

    If an active path to a disk fails, Dynamic Multi-Pathing automatically flags the failed path and no longer attempts to transfer data on it. The failed path is monitored and is automatically restored to service when Dynamic Multi-Pathing detects that the path functions correctly. Dynamic Multi-Pathing automatically updates path status on the user display when a path fails or is restored to service.

  • Dynamic path recognition

    If you add a new path to your Dynamic Multi-Pathing configuration, running a rescan or restarting your system causes Dynamic Multi-Pathing to detect the new path and display its status. If a failed or disabled path is restored to service, Dynamic Multi-Pathing automatically detects the status change and updates the display.