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Configure registry settings

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The Host Utilities require certain registry and parameter settings to verify that the Windows host correctly handles the storage system behavior.

Windows Host Utilities set the parameters that affect how the Windows host responds to a delay or loss of data. The particular values have been selected to verify that the Windows host correctly handles events such as the failover of one controller in the storage system to its partner controller.

Not all values apply to the device-specific module (DSM) for SANtricity Storage Manager; however, any overlap of values set by the Host Utilities and those set by the DSM for SANtricity Storage Manager do not result in conflicts.

FC, NVMe/FC, and iSCSI HBAs also have parameters that you must set to ensure best performance and to successfully handle storage system events.

The installation program supplied with Windows Unified Host Utilities sets the Windows, FC, and NVMe/FC HBA parameters to the supported values.

You must manually set the iSCSI HBA parameters.

The installer sets different values depending on whether you specify multipath I/O (MPIO) support when running the installation program.

Note You should not change these values unless NetApp technical support directs you to do so.

Registry values set by Windows Unified Host Utilities 7.2

The Windows Unified Host Utilities installer automatically sets registry values that are based on the choices that you make during the installation. You should be aware of these registry values and the operating system version.

The following values are set by the Windows Unified Host Utilities installer. All values are in decimal unless otherwise stated.

Note HKLM is the abbreviation for HKEY_LOCAL_MACHINE.
Registry key Value When set

HKLM\SYSTEM\CurrentControlSet\Services
\msdsm\Parameters
\DsmMaximumRetryTimeDuringStateTransition

120

When MPIO support is specified and your server is Windows Server 2012 R2,
Windows Server 2016 and Windows 2019, or Windows Server 2022

HKLM\SYSTEM\CurrentControlSet
\Services\msdsm\Parameters
\DsmMaximumStateTransitionTime

120

When MPIO support is specified and your server is Windows Server 2012 R2,
or Windows Server 2016, Windows 2019 or Windows Server 2022

HKLM\SYSTEM\CurrentControlSet\Services
\msdsm\Parameters\DsmSupportedDeviceList

"NETAPP LUN", "NETAPP LUN C-
Mode"
"NVMe NetApp ONTAO Con"

When MPIO support is specified

HKLM\SYSTEM\CurrentControlSet\Control
\Class\ {iSCSI_driver_GUID}\ instance_ID
\Parameters \IPSecConfigTimeout

60

Always

HKLM\SYSTEM\CurrentControlSet\Control
\Class\ {iSCSI_driver_GUID}\ instance_ID
\Parameters \LinkDownTime

10

Always

HKLM\SYSTEM\CurrentControlSet\Services
\ClusDisk \Parameters\ManageDisksOnSystemBuses

1

Always

HKLM\SYSTEM\CurrentControlSet\Control
\Class\ {iSCSI_driver_GUID}\ instance_ID
\Parameters \MaxRequestHoldTime

120

When no MPIO support is selected

HKLM\SYSTEM\CurrentControlSet\Control
\Class\ {iSCSI_driver_GUID}\ instance_ID
\Parameters \MaxRequestHoldTime

30

Always

HKLM\SYSTEM\CurrentControlSet\Control
\MPDEV\MPIOSupportedDeviceList

"NETAPP LUN",
"NETAPP LUN C-
Mode",
"NVMe NetApp ONTAO Con"

When MPIO support is specified

HKLM\SYSTEM\CurrentControlSet\Services\mpio
\Parameters\PathRecoveryInterval

30

When your server is Windows Server 2012 R2,
Windows Server 2016, Windows Server 2019, or Windows Server 2022

HKLM\SYSTEM\CurrentControlSet\Services\mpio
\Parameters\PathVerifyEnabled

1

When MPIO support is specified

HKLM\SYSTEM\CurrentControlSet\Services
\msdsm\Parameters\PathVerifyEnabled

1

When MPIO support is specified and your server is Windows Server 2012 R2,
Windows Server 2016, Windows Server 2019, or Windows Server 2022

HKLM\SYSTEM\CurrentControlSet\Services
\vnetapp\Parameters\PathVerifyEnabled

0

When MPIO support is specified

HKLM\SYSTEM\CurrentControlSet\Services
\mpio\Parameters\PDORemovePeriod

130

When MPIO support is specified

HKLM\SYSTEM\CurrentControlSet\Services\msdsm
\Parameters\PDORemovePeriod

130

When MPIO support is specified and your server is Windows Server 2012 R2,
Windows Server 2016 , Windows Server 2019, or Windows Server 2022

HKLM\SYSTEM\CurrentControlSet\Services\vnetapp
\Parameters\PDORemovePeriod

130

When MPIO support is specified, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services\mpio
\Parameters\RetryCount

6

When MPIO support is specified

HKLM\SYSTEM\CurrentControlSet\Services\msdsm
\Parameters\RetryCount

6

When MPIO support is specified and your server is Windows Server 2012 R2,
Windows Server 2016, Windows Server 2019, or Windows Server 2022

HKLM\SYSTEM\CurrentControlSet\Services\mpio
\Parameters\RetryInterval

1

When MPIO support is specified

HKLM\SYSTEM\CurrentControlSet\Services\msdsm
\Parameters\RetryInterval

1

When MPIO support is specified and your server is Windows Server 2012 R2,
Windows Server 2016, Windows Server 2019, or Windows Server 2022

HKLM\SYSTEM\CurrentControlSet\Services\vnetapp
\Parameters\RetryInterval

1

When MPIO support is specified

HKLM\SYSTEM\CurrentControlSet\Services
\disk\TimeOutValue

120

When no MPIO support is selected

HKLM\SYSTEM\CurrentControlSet\Services\mpio
\Parameters\UseCustomPathRecoveryInterval

1

When MPIO support is specified and your server is Windows Server 2012 R2,
Windows Server 2016, Windows Server 2019, or Windows Server 2022

NVMe parameters

The following NVMe Emulex driver parameters are updated when installing Windows Unified Host Utilities 7.2:

  • EnableNVMe = 1

  • NVMEMode = 0

  • LimTransferSize=1

Registry values set by Windows Unified Host Utilities 7.1

The Windows Unified Host Utilities installer automatically sets registry values that are based on the choices that you make during installation. You should be aware of these registry values, the operating system version.

The following values are set by the Windows Unified Host Utilities installer. All values are in decimal unless otherwise noted.

Note HKLM is the abbreviation for HKEY_LOCAL_MACHINE.
Registry key Value When set

HKLM\SYSTEM\CurrentControlSet\Services
\msdsm\Parameters
\DsmMaximumRetryTimeDuringStateTransition

120

When MPIO support is specified and your server is Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2, or Windows Server 2016, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services
\msdsm\Parameters
\DsmMaximumStateTransitionTime

120

When MPIO support is specified and your server is Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2, or Windows Server 2016, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services\msdsm
\Parameters\DsmSupportedDeviceList

"NETAPPLUN"

When MPIO support is specified

"NETAPP LUN", "NETAPP LUN C-Mode"

When MPIO support is specified, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Control\Class
{iSCSI_driver_GUID}\ instance_ID\Parameters
\IPSecConfigTimeout

60

Always, except when Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Control
\Class{iSCSI_driver_GUID}
\ instance_ID\Parameters\LinkDownTime

10

Always

HKLM\SYSTEM\CurrentControlSet\Services\ClusDisk
\Parameters\ManageDisksOnSystemBuses

1

Always, except when Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Control
\Class{iSCSI_driver_GUID}
\ instance_ID\Parameters\MaxRequestHoldTime

120

When no MPIO support is selected

30

Always, except when Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet
\Control\MPDEV\MPIOSupportedDeviceList

"NETAPP LUN"

When MPIO support is specified

"NETAPP LUN", "NETAPP LUN C-Mode"

When MPIO is support-specified, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services\mpio
\Parameters\PathRecoveryInterval

40

When your server is Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2, or Windows Server 2016 only

HKLM\SYSTEM\CurrentControlSet\Services\mpio
\Parameters\PathVerifyEnabled

0

When MPIO support is specified, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services\msdsm
\Parameters\PathVerifyEnabled

0

When MPIO support is specified, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services
\msdsm\Parameters\PathVerifyEnabled

0

When MPIO support is specified and your server is Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2, or Windows Server 2016, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services
\msiscdsm\Parameters\PathVerifyEnabled

0

When MPIO support is specified and your server is Windows Server 2003, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services\vnetapp
\Parameters\PathVerifyEnabled

0

When MPIO support is specified, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services\mpio
\Parameters\PDORemovePeriod

130

When MPIO support is specified, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services\msdsm
\Parameters\PDORemovePeriod

130

When MPIO support is specified and your server is Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2, or Windows Server 2016, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services\msiscdsm
\Parameters\PDORemovePeriod

130

When MPIO support is specified and your server is Windows Server 2003, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services
\vnetapp \Parameters\PDORemovePeriod

130

When MPIO support is specified, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services
\mpio\Parameters\RetryCount

6

When MPIO support is specified, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services\msdsm
\Parameters\RetryCount

6

When MPIO support is specified and your server is Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2, or Windows Server 2016, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services
\msiscdsm\Parameters\RetryCount

6

When MPIO support is specified and your server is Windows Server 2003, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services
\vnetapp\Parameters\RetryCount

6

When MPIO support is specified, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services
\mpio\Parameters\RetryInterval

1

When MPIO support is specified, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services
\msdsm\Parameters\RetryInterval

1

When MPIO support is specified and your server is Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2, or Windows Server 2016, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services
\vnetapp\Parameters\RetryInterval

1

When MPIO support is specified, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet
\Services\disk\TimeOutValue

120

When no MPIO support is selected, except if Data ONTAP DSM is detected

60

When MPIO support is specified, except if Data ONTAP DSM is detected

HKLM\SYSTEM\CurrentControlSet\Services\mpio
\Parameters\UseCustomPathRecoveryInterval

1

When your server is Windows Server 2008,Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2, or Windows Server 2016 only

See the Microsoft documents for the registry parameter details.

FC HBA values set by Windows Host Utilities

On systems using FC, the Host Utilities installer sets the required timeout values for Emulex and QLogic FC HBAs.

For Emulex FC HBAs, the installer sets the following parameters:

When MPIO is selected
Property type Property value

LinkTimeOut

1

NodeTimeOut

10
When MPIO is not selected
Property type Property value

LinkTimeOut

30

NodeTimeOut

120

For QLogic Fibre Channel HBAs, the installer sets the following parameters:

When MPIO is selected
Property type Property value

LinkDownTimeOut

1

PortDownRetryCount

10
When MPIO is not selected
Property type Property value

LinkDownTimeOut

30

PortDownRetryCount

120
Note The names of the parameters might vary slightly depending on the program.
For example, in the QLogic QConvergeConsole program, the parameter is displayed as Link Down Timeout.
The Host Utilities fcconfig.ini file displays this parameter as either LinkDownTimeOut or MpioLinkDownTimeOut, depending on whether MPIO is specified. However, all of these names refer to the same HBA parameter. See Emulex or QLogic to learn more about the timeout parameters.

Understand the Host Utilities changes to FC HBA driver settings

During the installation of the required Emulex or QLogic HBA drivers on an FC system, several parameters are checked and, in some cases, modified.

The Host Utilities set values for the following parameters if MS DSM for Windows MPIO is detected:

  • LinkTimeOut – defines the length of time in seconds that the host port waits before resuming I/O after a physical link is down.

  • NodeTimeOut – defines the length of time in seconds before the host port recognizes that a connection to the target device is down.

When troubleshooting HBA issues, check to make sure these settings have the correct values. The correct values depend on two factors:

  • The HBA vendor

  • Whether you are using multipathing software (MPIO)

You can correct the HBA settings by running the Repair option of the Windows Host Utilities installer.

Emulex HBA drivers

If you have an FC system, you must verify the Emulex HBA driver settings. These settings must exist for each port on the HBA.

Steps

  1. Open OnCommand Manager.

  2. Select the appropriate HBA from the list and click the Driver Parameters tab.

    The driver parameters appear.

    1. If you are using MPIO software, ensure that you have the following driver settings:

      • LinkTimeOut - 1

      • NodeTimeOut - 10

    2. If you are not using MPIO software, ensure that you have the following driver settings:

      • LinkTimeOut - 30

      • NodeTimeOut - 120

QLogic HBA drivers

On FC systems, you must verify the QLogic HBA driver settings. These settings must exist for each port on the HBA.

Steps

  1. Open QConvergeConsole, and then click Connect on the toolbar.

    The Connect to Host dialog box appears.

  2. Select the appropriate host from the list, and then select Connect.

    A list of HBAs appears in the FC HBA pane.

  3. Select the appropriate HBA port from the list, and then select the Settings tab.

  4. Select Advanced HBA Port Settings from the Select Settings section.

  5. If you are using MPIO software, verify that you have the following driver settings:

    • Link Down Timeout (linkdwnto) - 1

    • Port Down Retry Count (portdwnrc) - 10

  6. If you are not using MPIO software, verify that you have the following driver settings:

    • Link Down Timeout (linkdwnto) - 30

    • Port Down Retry Count (portdwnrc) - 120