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

Specifying control timer settings for an array

Control Timer Settings for an array are a set of tunable parameters that affect the testing of a path's status or health.

To specify control timer settings for an array

  1. To launch the Array Settings wizard, open the DMP DSMs folder in the tree view.
  2. Right-click the array that you are interested in and the array context menu appears.
  3. Select Array Settings from the path context menu.
  4. The Array Settings welcome screen appears. Click Next to continue.
  5. The Select Array Settings parameters screen appears.

    Edit the values for the parameters.

    Click Next to continue.

    The Control Timer Settings parameters are as follows:

    Test Path Retry Count

    The number of times DMP DSMs test a path to determine if it has recovered from an error condition. The default value is 0. The maximum value is 50.

    SCSI Command Timeout

    The amount of time a SCSI command waits for a device to respond to it. The default value is 30 seconds. The maximum value is 120 seconds.

    Kernel Sleep Time

    The interval of time the DMP DSMs kernel waits between attempts to recover a path from an error condition. The default value is 200 milliseconds. The maximum value is 10000 milliseconds.

    Failover Retry Count

    The number of times DMP DSMs attempt a failover to another path when the current path fails. The default value is 0. The maximum value is 50.

  6. The Array Settings summary screen appears displaying the settings for the array. Review the settings and click Finish to apply the settings and exit the wizard.

    For some load balance policies, such as round robin with Subset, additional specifications are required. The Array Settings wizard displays a screen before the summary screen to collect these specifications. Click Next after setting these specifications to continue to the summary screen.