CLUSCTL_RESOURCE_GET_FLAGS control code

Article
05/31/2018

Retrieves the flags that are set for a resource. Applications use this control code as a parameter to the ClusterResourceControl function, and resource DLLs receive the control code as a parameter to the ResourceControl callback function.

ClusterResourceControl( hResource,                  // resource handle
                        hHostNode,                  // optional host node
                        CLUSCTL_RESOURCE_GET_FLAGS, // this control code
                        NULL,                       // not used
                        0,                          // not used
                        lpOutBuffer,                // output buffer: DWORD bitmask
                        cbOutBufferSize,            // allocated buffer size (bytes)
                        lpcbBytesReturned );        // size of returned data (bytes)

Parameters

The following control code function and DLL support parameter is specific to this control code. For complete parameter descriptions, see ClusterResourceControl or ResourceControl.

lpOutBuffer

On a successful return, contains a DWORD bitmask describing flags set for the resource, as follows.

0

No flags are defined for the resource.

CLUS_FLAG_CORE (1)

This flag of the CLUS_FLAGS enumeration indicates that the resource or group is a core resource essential to the cluster and cannot be deleted. Included in this group of essential resources are the cluster IP Address, the cluster Network Name, and the quorum resource

Other nonzero

Indicates a user-defined flag created by a third party developer for a custom resource type.

Return value

ClusterResourceControl returns one of the following values.

ERROR_SUCCESS

The operation completed successfully. The lpcbBytesReturned parameter points to the actual size of the returned data.

ERROR_MORE_DATA

234 (0xEA)

More data is available. The output buffer pointed to by lpOutBuffer was not large enough to hold the data resulting from the operation. The lpcbBytesReturned parameter points to the size required for the output buffer.

System error code

If any other value is returned, then the operation failed. The value of lpcbBytesReturned is unreliable.

Implementations of ResourceControl can return the above values or the following value.

ERROR_INVALID_FUNCTION

Incorrect function. Requests that the Resource Monitor perform default processing (if any) for the control code addition to processing supplied by the DLL (if any).

Remarks

Do not use the CLUSCTL_RESOURCE_GET_FLAGS control code in any resource DLL entry point function. This control code can safely be called from a worker thread. For more information, see Function Calls to Avoid in Resource DLLs.

ClusAPI.h defines the 32 bits of CLUSCTL_RESOURCE_GET_FLAGS as follows:

Component	Bit location	Value
Object code	24 31	CLUS_OBJECT_RESOURCE (0x1)
Global bit	23	CLUS_NOT_GLOBAL (0x0)
Modify bit	22	CLUS_NO_MODIFY (0x0)
User bit	21	CLCTL_CLUSTER_BASE (0x0)
Type bit	20	External (0x0)
Operation code	0 23	CLCTL_GET_FLAGS (0x9)
Access code	0 1	CLUS_ACCESS_READ (0x1)

For more information, see Control Code Architecture.

Resource DLL Support

Optional. Support CLUSCTL_RESOURCE_GET_FLAGS only if you define flags specific to the resources supported by your DLL. The Failover Cluster API reserves only the lower 16 bits of the DWORD bitmask. Use the upper 16 bits to define your own resource-specific flags. Be sure to document or otherwise communicate what your flags do and how they should be used.

If you do not define resource-specific flags, return ERROR_INVALID_FUNCTION to let the Resource Monitor handle the operation. The Resource Monitor will read the Flags value from the resource key in the cluster database.

For more information on the ResourceControl entry point function, see Implementing ResourceControl.

Requirements


Minimum supported client	None supported
Minimum supported server	Windows Server 2008 Enterprise, Windows Server 2008 Datacenter
Header	ClusAPI.h

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