Volume Shadow Copy Service

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Applies to: Windows Server 2022, Windows Server 2019, Windows Server 2016, Windows Server 2012 R2, Windows Server 2012, and Windows Server 2008 R2, Windows Server 2008, Windows ten, Windows 8.1, Windows 8, Windows 7

Backing up and restoring disquisitional business organization data can exist very circuitous due to the post-obit issues:

  • The data usually needs to be backed up while the applications that produce the data are still running. This ways that some of the data files might be open or they might be in an inconsistent state.

  • If the data fix is large, it can be difficult to back up all of it at one time.

Correctly performing backup and restore operations requires close coordination between the backup applications, the line-of-business organization applications that are being backed up, and the storage management hardware and software. The Volume Shadow Copy Service (VSS), which was introduced in Windows Server® 2003, facilitates the conversation between these components to let them to work meliorate together. When all the components support VSS, you tin can use them to support your application data without taking the applications offline.

VSS coordinates the deportment that are required to create a consistent shadow copy (also known as a snapshot or a bespeak-in-time copy) of the data that is to be backed up. The shadow copy tin be used as-is, or it tin be used in scenarios such equally the following:

  • You want to back up awarding information and system land data, including archiving information to another hard deejay drive, to tape, or to other removable media.

  • You are information mining.

  • You are performing disk-to-disk backups.

  • You need a fast recovery from data loss by restoring data to the original Logical Unit of measurement Number (LUN) or to an entirely new LUN that replaces an original LUN that failed.

Windows features and applications that use VSS include the post-obit:

  • Windows Server Backup (https://become.microsoft.com/fwlink/?LinkId=180891)

  • Shadow Copies of Shared Folders (https://go.microsoft.com/fwlink/?LinkId=142874)

  • System Center Data Protection Manager (https://go.microsoft.com/fwlink/?LinkId=180892)

  • System Restore (https://go.microsoft.com/fwlink/?LinkId=180893)

How Volume Shadow Copy Service Works

A complete VSS solution requires all of the following basic parts:

VSS service   Part of the Windows operating organisation that ensures the other components can communicate with each other properly and piece of work together.

VSS requester   The software that requests the actual creation of shadow copies (or other loftier-level operations like importing or deleting them). Typically, this is the backup application. The Windows Server Fill-in utility and the Organisation Heart Data Protection Manager application are VSS requesters. Non-Microsoft® VSS requesters include about all backup software that runs on Windows.

VSS author   The component that guarantees nosotros have a consistent data ready to back up. This is typically provided as part of a line-of-concern awarding, such equally SQL Server® or Exchange Server. VSS writers for various Windows components, such as the registry, are included with the Windows operating organization. Non-Microsoft VSS writers are included with many applications for Windows that need to guarantee data consistency during back up.

VSS provider   The component that creates and maintains the shadow copies. This can occur in the software or in the hardware. The Windows operating system includes a VSS provider that uses copy-on-write. If you employ a storage area network (SAN), it is important that you install the VSS hardware provider for the SAN, if ane is provided. A hardware provider offloads the task of creating and maintaining a shadow re-create from the host operating system.

The following diagram illustrates how the VSS service coordinates with requesters, writers, and providers to create a shadow copy of a volume.

Architectural diagram of Volume Shadow Copy Service

Effigy 1   Architectural diagram of Volume Shadow Re-create Service

How a Shadow Copy Is Created

This department puts the various roles of the requester, writer, and provider into context by listing the steps that need to be taken to create a shadow copy. The post-obit diagram shows how the Volume Shadow Copy Service controls the overall coordination of the requester, writer, and provider.

Diagram how Volume Shadow Copy Service works

Figure 2 Shadow copy creation process

To create a shadow copy, the requester, writer, and provider perform the post-obit actions:

  1. The requester asks the Book Shadow Copy Service to enumerate the writers, gather the writer metadata, and ready for shadow copy creation.

  2. Each author creates an XML clarification of the components and information stores that need to exist backed up and provides it to the Volume Shadow Copy Service. The writer also defines a restore method, which is used for all components. The Volume Shadow Re-create Service provides the author's clarification to the requester, which selects the components that will be backed upward.

  3. The Book Shadow Copy Service notifies all the writers to prepare their information for making a shadow copy.

  4. Each writer prepares the data every bit appropriate, such as completing all open transactions, rolling transaction logs, and flushing caches. When the information is ready to be shadow-copied, the writer notifies the Volume Shadow Copy Service.

  5. The Volume Shadow Copy Service tells the writers to temporarily freeze awarding write I/O requests (read I/O requests are still possible) for the few seconds that are required to create the shadow re-create of the volume or volumes. The application freeze is not allowed to take longer than 60 seconds. The Book Shadow Copy Service flushes the file organization buffers and so freezes the file system, which ensures that the file arrangement metadata is recorded correctly and the data to be shadow-copied is written in a consistent order.

  6. The Volume Shadow Copy Service tells the provider to create the shadow copy. The shadow copy cosmos period lasts no more than than 10 seconds, during which all write I/O requests to the file system remain frozen.

  7. The Book Shadow Re-create Service releases file system write I/O requests.

  8. VSS tells the writers to thaw application write I/O requests. At this bespeak applications are free to resume writing data to the deejay that is being shadow-copied.

Note

The shadow re-create creation can exist aborted if the writers are kept in the freeze state for longer than 60 seconds or if the providers take longer than 10 seconds to commit the shadow re-create.

  1. The requester tin can retry the process (become dorsum to stride 1) or notify the administrator to retry at a later fourth dimension.

  2. If the shadow re-create is successfully created, the Volume Shadow Copy Service returns the location information for the shadow copy to the requester. In some cases, the shadow copy tin can be temporarily made bachelor as a read-write volume so that VSS and one or more applications tin can change the contents of the shadow copy before the shadow copy is finished. After VSS and the applications make their alterations, the shadow copy is made read-just. This phase is called Auto-recovery, and it is used to undo any file-arrangement or awarding transactions on the shadow re-create volume that were non completed before the shadow copy was created.

How the Provider Creates a Shadow Copy

A hardware or software shadow copy provider uses one of the post-obit methods for creating a shadow re-create:

Complete re-create   This method makes a complete copy (called a "full re-create" or "clone") of the original volume at a given indicate in time. This copy is read-only.

Re-create-on-write   This method does not re-create the original volume. Instead, information technology makes a differential re-create past copying all changes (completed write I/O requests) that are made to the book afterward a given point in time.

Redirect-on-write   This method does non re-create the original volume, and it does not make any changes to the original volume after a given point in time. Instead, it makes a differential re-create by redirecting all changes to a different volume.

Complete copy

A complete copy is usually created by making a "carve up mirror" as follows:

  1. The original volume and the shadow re-create volume are a mirrored book set.

  2. The shadow copy volume is separated from the original volume. This breaks the mirror connection.

After the mirror connection is broken, the original book and the shadow copy volume are contained. The original volume continues to accept all changes (write I/O requests), while the shadow copy volume remains an verbal read-only copy of the original data at the time of the intermission.

Re-create-on-write method

In the copy-on-write method, when a change to the original volume occurs (but earlier the write I/O asking is completed), each block to be modified is read and then written to the volume's shadow re-create storage expanse (also chosen its "diff area"). The shadow copy storage area tin be on the same volume or a different volume. This preserves a copy of the information block on the original volume before the change overwrites it.

Time Source data (status and data) Shadow re-create (condition and information)

T0

Original data: 1 2 3 4 five

No copy: —

T1

Data inverse in enshroud: 3 to iii'

Shadow re-create created (differences simply): 3

T2

Original data overwritten: ane two 3' four 5

Differences and index stored on shadow copy: 3

Table 1   The copy-on-write method of creating shadow copies

The copy-on-write method is a quick method for creating a shadow copy, because it copies only data that is changed. The copied blocks in the diff area tin be combined with the changed data on the original volume to restore the volume to its land before any of the changes were made. If at that place are many changes, the re-create-on-write method can get expensive.

Redirect-on-write method

In the redirect-on-write method, whenever the original book receives a alter (write I/O asking), the change is not applied to the original volume. Instead, the change is written to another volume'due south shadow copy storage area.

Time Source data (status and data) Shadow copy (condition and data)

T0

Original data: 1 2 3 iv five

No copy: —

T1

Information changed in cache: three to three'

Shadow copy created (differences just): iii'

T2

Original data unchanged: 1 two iii four 5

Differences and index stored on shadow copy: 3'

Table 2   The redirect-on-write method of creating shadow copies

Similar the copy-on-write method, the redirect-on-write method is a quick method for creating a shadow copy, because it copies just changes to the information. The copied blocks in the diff area tin be combined with the unchanged information on the original volume to create a complete, upward-to-date copy of the data. If there are many read I/O requests, the redirect-on-write method can go expensive.

Shadow Re-create Providers

There are 2 types of shadow copy providers: hardware-based providers and software-based providers. There is also a organization provider, which is a software provider that is built in to the Windows operating system.

Hardware-based providers

Hardware-based shadow copy providers act as an interface between the Volume Shadow Copy Service and the hardware level by working in conjunction with a hardware storage adapter or controller. The work of creating and maintaining the shadow copy is performed by the storage array.

Hardware providers always have the shadow copy of an unabridged LUN, but the Volume Shadow Copy Service merely exposes the shadow copy of the volume or volumes that were requested.

A hardware-based shadow copy provider makes employ of the Volume Shadow Copy Service functionality that defines the point in time, allows data synchronization, manages the shadow copy, and provides a common interface with fill-in applications. Nonetheless, the Volume Shadow Copy Service does not specify the underlying machinery by which the hardware-based provider produces and maintains shadow copies.

Software-based providers

Software-based shadow copy providers typically intercept and process read and write I/O requests in a software layer betwixt the file system and the volume managing director software.

These providers are implemented equally a user-mode DLL component and at least one kernel-fashion device commuter, typically a storage filter driver. Unlike hardware-based providers, software-based providers create shadow copies at the software level, non the hardware level.

A software-based shadow re-create provider must maintain a "point-in-time" view of a book by having admission to a data set that tin can be used to re-create book condition before the shadow copy creation fourth dimension. An case is the copy-on-write technique of the arrangement provider. However, the Volume Shadow Copy Service places no restrictions on what technique the software-based providers utilise to create and maintain shadow copies.

A software provider is applicable to a wider range of storage platforms than a hardware-based provider, and information technology should piece of work with bones disks or logical volumes as well. (A logical volume is a volume that is created past combining costless space from 2 or more disks.) In contrast to hardware shadow copies, software providers consume operating system resources to maintain the shadow copy.

For more information virtually basic disks, encounter What Are Basic Disks and Volumes? (https://become.microsoft.com/fwlink/?LinkId=180894) on TechNet.

System provider

I shadow copy provider, the organization provider, is supplied in the Windows operating arrangement. Although a default provider is supplied in Windows, other vendors are gratis to supply implementations that are optimized for their storage hardware and software applications.

To maintain the "bespeak-in-time" view of a volume that is independent in a shadow re-create, the arrangement provider uses a copy-on-write technique. Copies of the blocks on volume that accept been modified since the starting time of the shadow copy creation are stored in a shadow copy storage area.

The organization provider can betrayal the production volume, which can be written to and read from commonly. When the shadow copy is needed, it logically applies the differences to data on the production volume to expose the consummate shadow re-create.

For the system provider, the shadow copy storage surface area must be on an NTFS volume. The book to be shadow copied does not need to be an NTFS volume, but at least 1 volume mounted on the system must be an NTFS volume.

The component files that make up the arrangement provider are swprv.dll and volsnap.sys.

In-Box VSS Writers

The Windows operating system includes a fix of VSS writers that are responsible for enumerating the data that is required past diverse Windows features.

For more information about these writers, see the following Microsoft Docs Spider web page:

  • In-Box VSS Writers

How Shadow Copies Are Used

In addition to backing up application data and arrangement state data, shadow copies can exist used for a number of purposes, including the following:

  • Restoring LUNs (LUN resynchronization and LUN swapping)

  • Restoring private files (Shadow Copies for Shared Folders)

  • Information mining past using transportable shadow copies

Restoring LUNs (LUN resynchronization and LUN swapping)

In Windows Server 2008 R2 and Windows 7, VSS requesters can use a hardware shadow copy provider feature chosen LUN resynchronization (or "LUN resync"). This is a fast-recovery scheme that allows an application administrator to restore information from a shadow copy to the original LUN or to a new LUN.

The shadow copy can be a full clone or a differential shadow copy. In either case, at the end of the resync functioning, the destination LUN volition accept the same contents as the shadow copy LUN. During the resync functioning, the array performs a block-level re-create from the shadow re-create to the destination LUN.

Note

The shadow copy must be a transportable hardware shadow copy.

Well-nigh arrays allow product I/O operations to resume shortly subsequently the resync operation begins. While the resync operation is in progress, read requests are redirected to the shadow copy LUN, and write requests to the destination LUN. This allows arrays to recover very large information sets and resume normal operations in several seconds.

LUN resynchronization is dissimilar from LUN swapping. A LUN swap is a fast recovery scenario that VSS has supported since Windows Server 2003 SP1. In a LUN bandy, the shadow copy is imported and so converted into a read-write volume. The conversion is an irreversible operation, and the volume and underlying LUN cannot exist controlled with the VSS APIs after that. The post-obit list describes how LUN resynchronization compares with LUN swapping:

  • In LUN resynchronization, the shadow copy is not altered, so it tin can be used several times. In LUN swapping, the shadow copy tin can be used only one time for a recovery. For the most safe-conscious administrators, this is important. When LUN resynchronization is used, the requester tin can retry the entire restore operation if something goes wrong the first time.

  • At the end of a LUN swap, the shadow copy LUN is used for product I/O requests. For this reason, the shadow copy LUN must use the same quality of storage as the original production LUN to ensure that performance is non impacted after the recovery operation. If LUN resynchronization is used instead, the hardware provider can maintain the shadow copy on storage that is less expensive than production-quality storage.

  • If the destination LUN is unusable and needs to exist recreated, LUN swapping may be more economical because it doesn't require a destination LUN.

Warning

All of the operations listed are LUN-level operations. If y'all attempt to recover a specific volume past using LUN resynchronization, yous are unwittingly going to revert all the other volumes that are sharing the LUN.

Restoring individual files (Shadow Copies for Shared Folders)

Shadow Copies for Shared Folders uses the Volume Shadow Copy Service to provide betoken-in-time copies of files that are located on a shared network resources, such as a file server. With Shadow Copies for Shared Folders, users tin quickly recover deleted or changed files that are stored on the network. Because they can do so without administrator assist, Shadow Copies for Shared Folders can increase productivity and reduce administrative costs.

For more than information nigh Shadow Copies for Shared Folders, see Shadow Copies for Shared Folders (https://become.microsoft.com/fwlink/?LinkId=180898) on TechNet.

Information mining by using transportable shadow copies

With a hardware provider that is designed for employ with the Volume Shadow Copy Service, you tin can create transportable shadow copies that tin can be imported onto servers inside the same subsystem (for example, a SAN). These shadow copies can be used to seed a production or test installation with read-only data for information mining.

With the Volume Shadow Copy Service and a storage array with a hardware provider that is designed for use with the Volume Shadow Copy Service, it is possible to create a shadow copy of the source data volume on i server, and then import the shadow copy onto some other server (or back to the same server). This process is achieved in a few minutes, regardless of the size of the data. The ship process is achieved through a series of steps that apply a shadow copy requester (a storage-management application) that supports transportable shadow copies.

To transport a shadow copy

  1. Create a transportable shadow copy of the source data on a server.

  2. Import the shadow copy to a server that is connected to the SAN (you can import to a different server or the same server).

  3. The data is at present gear up to be used.

Diagram how to transport a shadow copy between two servers

Effigy three   Shadow re-create creation and transport between 2 servers

Annotation

A transportable shadow copy that is created on Windows Server 2003 cannot exist imported onto a server that is running Windows Server 2008 or Windows Server 2008 R2. A transportable shadow re-create that was created on Windows Server 2008 or Windows Server 2008 R2 cannot be imported onto a server that is running Windows Server 2003. However, a shadow copy that is created on Windows Server 2008 can be imported onto a server that is running Windows Server 2008 R2 and vice versa.

Shadow copies are read-only. If you desire to catechumen a shadow copy to a read/write LUN, you tin can utilise a Virtual Disk Service-based storage-management application (including some requesters) in improver to the Volume Shadow Copy Service. Past using this application, y'all can remove the shadow copy from Volume Shadow Copy Service direction and convert information technology to a read/write LUN.

Volume Shadow Copy Service transport is an avant-garde solution on computers running Windows Server 2003 Enterprise Edition, Windows Server 2003 Datacenter Edition, Windows Server 2008, or Windows Server 2008 R2. It works only if there is a hardware provider on the storage array. Shadow copy ship tin can exist used for a number of purposes, including tape backups, data mining, and testing.

Ofttimes Asked Questions

This FAQ answers questions about Book Shadow Copy Service (VSS) for system administrators. For information nearly VSS application programming interfaces, see Volume Shadow Copy Service (https://go.microsoft.com/fwlink/?LinkId=180899) in the Windows Developer Center Library.

When was Book Shadow Copy Service introduced? On which Windows operating organisation versions is it available?

VSS was introduced in Windows XP. It is available on Windows XP, Windows Server 2003, Windows Vista®, Windows Server 2008, Windows 7, and Windows Server 2008 R2.

What is the difference betwixt a shadow copy and a backup?

In the case of a hd backup, the shadow copy created is as well the fill-in. Data can be copied off the shadow copy for a restore or the shadow copy tin be used for a fast recovery scenario—for example, LUN resynchronization or LUN swapping.

When information is copied from the shadow copy to tape or other removable media, the content that is stored on the media constitutes the backup. The shadow copy itself can exist deleted after the data is copied from information technology.

What is the largest size volume that Book Shadow Copy Service supports?

Volume Shadow Copy Service supports a book size of up to 64 TB.

I made a backup on Windows Server 2008. Tin can I restore it on Windows Server 2008 R2?

It depends on the fill-in software that you used. Most backup programs support this scenario for information but not for organization state backups.

Shadow copies that are created on either of these versions of Windows tin be used on the other.

I fabricated a backup on Windows Server 2003. Tin can I restore information technology on Windows Server 2008?

It depends on the backup software you lot used. If you create a shadow copy on Windows Server 2003, yous cannot use it on Windows Server 2008. Also, if y'all create a shadow copy on Windows Server 2008, you cannot restore it on Windows Server 2003.

How tin can I disable VSS?

It is possible to disable the Volume Shadow Copy Service by using the Microsoft Direction Panel. Nevertheless, you should not do this. Disabling VSS adversely affects any software you use that depends on it, such as Organisation Restore and Windows Server Backup.

For more information, run across the post-obit Microsoft TechNet Web sites:

  • System Restore (https://go.microsoft.com/fwlink/?LinkID=157113)

  • Windows Server Backup (https://go.microsoft.com/fwlink/?LinkID=180891)

Tin I exclude files from a shadow copy to salve infinite?

VSS is designed to create shadow copies of entire volumes. Temporary files, such equally paging files, are automatically omitted from shadow copies to save space.

To exclude specific files from shadow copies, utilise the following registry central: FilesNotToSnapshot.

Annotation

The FilesNotToSnapshot registry key is intended to exist used only by applications. Users who endeavour to employ it will encounter limitations such as the following:

  • It cannot delete files from a shadow re-create that was created on a Windows Server past using the Previous Versions feature.
  • It cannot delete files from shadow copies for shared folders.
  • It can delete files from a shadow re-create that was created by using the Diskshadow utility, merely it cannot delete files from a shadow copy that was created by using the Vssadmin utility.
  • Files are deleted from a shadow copy on a best-effort basis. This ways that they are not guaranteed to be deleted.

For more than information, meet Excluding Files from Shadow Copies (https://go.microsoft.com/fwlink/?LinkId=180904) on MSDN.

My not-Microsoft backup program failed with a VSS error. What can I do?

Check the product support department of the Web site of the company that created the fill-in programme. There may be a product update that you can download and install to fix the problem. If not, contact the company's product support section.

Arrangement administrators can use the VSS troubleshooting information on the following Microsoft TechNet Library Web site to gather diagnostic information about VSS-related issues.

For more information, see Volume Shadow Copy Service (https://become.microsoft.com/fwlink/?LinkId=180905) on TechNet.

What is the "unequal surface area"?

The shadow copy storage area (or "diff area") is the location where the data for the shadow re-create that is created past the organisation software provider is stored.

Where is the diff expanse located?

The diff area can exist located on whatever local volume. However, it must be located on an NTFS book that has enough space to store it.

How is the diff surface area location determined?

The following criteria are evaluated, in this order, to determine the unequal area location:

  • If a volume already has an existing shadow copy, that location is used.

  • If in that location is a preconfigured manual association between the original volume and the shadow copy volume location, then that location is used.

  • If the previous two criteria exercise not provide a location, the shadow copy service chooses a location based on available complimentary infinite. If more than ane volume is being shadow copied, the shadow copy service creates a list of possible snapshot locations based on the size of complimentary space, in descending order. The number of locations provided is equal to the number of volumes being shadow copied.

  • If the volume being shadow copied is i of the possible locations, then a local association is created. Otherwise an association with the volume with the most available space is created.

Can VSS create shadow copies of not-NTFS volumes?

Yep. However, persistent shadow copies tin can be made but for NTFS volumes. In add-on, at least one book mounted on the system must exist an NTFS book.

What's the maximum number of shadow copies I tin can create at 1 fourth dimension?

The maximum number of shadow copied volumes in a single shadow copy prepare is 64. Notation that this is not the aforementioned as the number of shadow copies.

What's the maximum number of software shadow copies created by the system provider that I tin can maintain for a volume?

The max number is of software shadow copies for each volume is 512. Notwithstanding, by default y'all tin but maintain 64 shadow copies that are used past the Shadow Copies of Shared Folders characteristic. To modify the limit for the Shadow Copies of Shared Folders feature, use the post-obit registry fundamental: MaxShadowCopies.

How can I control the space that is used for shadow re-create storage space?

Blazon the vssadmin resize shadowstorage command.

For more information, see Vssadmin resize shadowstorage (https://go.microsoft.com/fwlink/?LinkId=180906) on TechNet.

What happens when I run out of space?

Shadow copies for the volume are deleted, kickoff with the oldest shadow copy.

The Windows operating arrangement provides the post-obit tools for working with VSS:

  • DiskShadow (https://go.microsoft.com/fwlink/?LinkId=180907)

  • VssAdmin (https://go.microsoft.com/fwlink/?LinkId=84008)

DiskShadow

DiskShadow is a VSS requester that y'all can employ to manage all the hardware and software snapshots that y'all tin accept on a system. DiskShadow includes commands such as the following:

  • list: Lists VSS writers, VSS providers, and shadow copies

  • create: Creates a new shadow copy

  • import: Imports a transportable shadow re-create

  • expose: Exposes a persistent shadow copy (every bit a drive letter, for example)

  • revert: Reverts a book back to a specified shadow re-create

This tool is intended for apply past Information technology professionals, but developers might as well observe it useful when testing a VSS writer or VSS provider.

DiskShadow is available but on Windows Server operating systems. It is non bachelor on Windows client operating systems.

VssAdmin

VssAdmin is used to create, delete, and list data near shadow copies. It can also be used to resize the shadow re-create storage area ("diff area").

VssAdmin includes commands such equally the following:

  • create shadow: Creates a new shadow copy

  • delete shadows: Deletes shadow copies

  • list providers: Lists all registered VSS providers

  • list writers: Lists all subscribed VSS writers

  • resize shadowstorage: Changes the maximum size of the shadow copy storage area

VssAdmin can merely be used to administer shadow copies that are created by the system software provider.

VssAdmin is available on Windows client and Windows Server operating organization versions.

Volume Shadow Copy Service Registry Keys

The following registry keys are available for utilise with VSS:

  • VssAccessControl

  • MaxShadowCopies

  • MinDiffAreaFileSize

VssAccessControl

This cardinal is used to specify which users have access to shadow copies.

For more information, see the post-obit entries on the MSDN Web site:

  • Security Considerations for Writers (https://go.microsoft.com/fwlink/?LinkId=157739)

  • Security Considerations for Requesters (https://go.microsoft.com/fwlink/?LinkId=180908)

MaxShadowCopies

This cardinal specifies the maximum number of client-accessible shadow copies that tin be stored on each volume of the computer. Client-accessible shadow copies are used by Shadow Copies for Shared Folders.

For more information, see the following entry on the MSDN Web site:

MaxShadowCopies nether Registry Keys for Backup and Restore (https://go.microsoft.com/fwlink/?LinkId=180909)

MinDiffAreaFileSize

This key specifies the minimum initial size, in MB, of the shadow copy storage expanse.

For more information, meet the post-obit entry on the MSDN Spider web site:

MinDiffAreaFileSize nether Registry Keys for Backup and Restore (https://go.microsoft.com/fwlink/?LinkId=180910)

Supported Operating Organisation Versions

The following tabular array lists the minimum supported operating system versions for VSS features.

VSS feature Minimum supported client Minimum supported server

LUN resynchronization

None supported

Windows Server 2008 R2

FilesNotToSnapshot registry key

Windows Vista

Windows Server 2008

Transportable shadow copies

None supported

Windows Server 2003 with SP1

Hardware shadow copies

None supported

Windows Server 2003

Previous versions of Windows Server

Windows Vista

Windows Server 2003

Fast recovery using LUN swap

None supported

Windows Server 2003 with SP1

Multiple imports of hardware shadow copies

Annotation
This is the ability to import a shadow re-create more than than one time. Only one import operation can be performed at a time.

None supported

Windows Server 2008

Shadow Copies for Shared Folders

None supported

Windows Server 2003

Transportable auto-recovered shadow copies

None supported

Windows Server 2008

Concurrent backup sessions (up to 64)

Windows XP

Windows Server 2003

Unmarried restore session concurrent with backups

Windows Vista

Windows Server 2003 with SP2

Up to 8 restore sessions concurrent with backups

Windows 7

Windows Server 2003 R2

Additional References

Book Shadow Copy Service in Windows Developer Center