IVdsLunMpio::GetLoadBalancePolicy method (vdshwprv.h)

Article
02/09/2023

[Beginning with Windows 8 and Windows Server 2012, the Virtual Disk Service COM interface is superseded by the Windows Storage Management API.]

Returns the current load balance policy on the LUN.

Syntax

HRESULT GetLoadBalancePolicy(
  [out] VDS_LOADBALANCE_POLICY_ENUM *pPolicy,
  [out] VDS_PATH_POLICY             **ppPaths,
  [out] LONG                        *plNumberOfPaths
);

Parameters

[out] pPolicy

A pointer to a variable that receives an VDS_LOADBALANCE_POLICY_ENUM enumeration value that specifies the load balance policy.

[out] ppPaths

A pointer to the array of VDS_PATH_POLICY structures passed in by the caller. Callers must free this array by using the CoTaskMemFree function.

[out] plNumberOfPaths

A pointer to a variable that receives the number of path-specific policy information structures returned in the ppPaths parameter.

Return value

This method can return standard HRESULT values, such as E_INVALIDARG or E_OUTOFMEMORY, and VDS-specific return values. It can also return converted system error codes using the HRESULT_FROM_WIN32 macro. Errors can originate from VDS itself or from the underlying VDS provider that is being used. Possible return values include the following.

Return code/value	Description
S_OK	The load balance policy was successfully returned. If the LUN has no paths, the array is empty, the value pointed to by the plNumberOfPaths parameter is set to 0, and the value pointed to by the ppPaths parameter is set to NULL.
VDS_E_PROVIDER_CACHE_CORRUPT 0x8004241FL	The cache of the provider is corrupted. This indicates a software or communication problem inside a provider that caches information about the attached devices. The caller can use the IVdsHwProvider::Reenumerate method followed by the IVdsHwProvider::Refresh method to restore the cache.
VDS_E_OBJECT_DELETED 0x8004240BL	The LUN object is no longer present.
VDS_E_OBJECT_STATUS_FAILED 0x80042431L	The LUN is in a failed state and is unable to perform the requested operation.
VDS_E_ANOTHER_CALL_IN_PROGRESS 0x80042404L	Another operation is in progress. This operation cannot proceed until previous operations are complete.

Remarks

The number of paths returned by this method will match the number of paths returned by the IVdsLunMpio::GetPathInfo method.

Requirements

Requirement	Value
Minimum supported client	Windows Vista [desktop apps only]
Minimum supported server	Windows Server 2003 R2 [desktop apps only]
Target Platform	Windows
Header	vdshwprv.h