VSS_RESTORE_TARGET enumeration (vswriter.h)

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The VSS_RESTORE_TARGET enumeration is used by a writer at restore time to indicate how all the files included in a selected component, and all the files in any component set it defines, are to be restored. (See Working with Selectability and Logical Paths for information on selecting components.)

Setting a restore target modifies or overrides the restore method set during backup (see VSS_RESTOREMETHOD_ENUM).

Syntax

typedef enum VSS_RESTORE_TARGET {
  VSS_RT_UNDEFINED = 0,
  VSS_RT_ORIGINAL,
  VSS_RT_ALTERNATE,
  VSS_RT_DIRECTED,
  VSS_RT_ORIGINAL_LOCATION
} ;

Constants

 
VSS_RT_UNDEFINED
Value: 0
No target is defined.


This value indicates an error on the part of the writer.

This value is not supported for express writers.
VSS_RT_ORIGINAL
This is the default restore target.


This value indicates that the restoration of the files included in a selected component (or the component set
defined by that component) should proceed according to the original restore method specified at backup time by
a VSS_RESTOREMETHOD_ENUM value.
VSS_RT_ALTERNATE
The files are restored to a location determined from an existing alternate location mapping.


The restore target should be set to VSS_RT_ALTERNATE only when alternate location
mappings have been set for all the files managed by a selected component or component set.

This value is not supported for express writers.
VSS_RT_DIRECTED
Use directed targeting by the writer at restore time to restore a file.


Directed targeting allows a writer to control, on a file-by-file basis, how a file is
restored—indicating how much of a file is to be restored and into which files the
backed-up file is to be restored.

This value is not supported for express writers.
VSS_RT_ORIGINAL_LOCATION
The files are restored to the location at which they were at backup time, even if the original
restore method that was specified at backup time was
VSS_RME_RESTORE_TO_ALTERNATE_LOCATION.


Windows Server 2003 and Windows XP:  This value is not supported.

This value is not supported for express writers.

Remarks

A target of VSS_RT_UNDEFINED indicates an error state.

At backup time, writers set the default restore behavior by indicating a restore method (VSS_RESTOREMETHOD_ENUM) set with IVssCreateWriterMetadata::SetRestoreMethod.

If a writer does not explicitly set the restore target of a component and any component set it defines, by default it is set to VSS_RT_ORIGINAL.

At restore time, a VSS_RESTORE_TARGET value other than VSS_RT_ORIGINAL overrides the value of the originally specified restore method specified by VSS_RESTOREMETHOD_ENUM and set by IVssCreateWriterMetadata::SetRestoreMethod.

Only writers (using IVssComponent::SetRestoreTarget) can set a restore target (VSS_RESTORE_TARGET) and change how files are restored overriding the restore method).

Requesters and writers can access the current restore target through IVssComponent::GetRestoreTarget.

A restore target of VSS_RT_ORIGINAL does not mean that files should be restored to their original location, but that the originally specified restore method (VSS_RESTOREMETHOD_ENUM) must be respected. For instance, if a writer set a restore method of VSS_RME_RESTORE_TO_ALTERNATE_LOCATION for a selected component and the restore target is VSS_RT_ORIGINAL, files should be restored to the alternate location defined by the writer.

(In this example, if a writer has failed to define alternate location mappings, then it is a writer error, and the requester should report it.)

A restore target of VSS_RT_ALTERNATE without an alternate location mapping defined constitutes a writer error, and the requester should report it as such.

See Non-Default Backup And Restore Locations for more information.

Requirements

Requirement Value
Minimum supported client Windows XP [desktop apps only]
Minimum supported server Windows Server 2003 [desktop apps only]
Header vswriter.h

See also

IVssComponent::GetRestoreTarget

IVssComponent::SetRestoreTarget

VSS_RESTOREMETHOD_ENUM