![3D"ws-HmSvr_h_rgb"](3D"1WindowsHomeServerTechnicalBrief-DriveExtender_files/image005.gif")
Technical Brief
Microsoft Corporation
Published: August 2008
Version: 1.1
Abstract
This technical brief provides an in-depth look at the features and functionality of Windows® Home Server Drive Extender. T= he brief has been updated to include additional information for Windows Home Server Power Pack 1.
To learn more about other aspects of Windows Home Server, see the Microsoft Web site (http://go.microsoft.com/fwlink/?LinkId= =3D100260).
![3DDocCoverBottom](3D"1WindowsHomeServerTechnicalBrief-DriveExtender_files/image007.gif")
The information contai=
ned in
this document represents the current view of Microsoft Corporation on the
issues discussed as of the date of publication. Because Microsoft must resp=
ond
to changing market conditions, it should not be interpreted to be a commitm=
ent
on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any
information presented after the date of publication.
This Technical Brief i=
s for
informational purposes only. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIE=
D OR
STATUTORY, AS TO THE INFORMATION IN THIS DOCUMENT.
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property of their respective owners.
Contents
Windows&re= g; Home Server Drive Extender is a new storage technology that enables y= ou to use internal and external hard drives for additional storage on your home server. In addition, you can enable Folder Duplication for specific shared = folders on their home servers. Maintaining two copies of a shared folder on separate hard drives helps protect against the failure of a single hard drive.
Features and Functionality
The core features of Windows Home Server Drive Extende= r are:
· = Predefined Shared Folders
Your home s= erver is preconfigured with shared folders named Photos, Music, Videos, Public, a= nd Software. From the Windows Home Server Console you can specify user permiss= ions for these folders and create new shared folders. You can easily move files = and folders from your home computers into the shared folders on your home serve= r by using a drag-and-drop operation.
· = Easy to add more storage
From the Wi= ndows Home Server Console, you can add a new hard drive to your home server= by following a simple wizard. The amount of storage available to your shared folders and home computer backups increases proportionally. The hard drives= you add can be either internal or external (for example, USB 2.0 or FireWire).<= /p>
· = Shared Folder duplication
If you have= two or more hard drives on your home server, Windows Home Server helps protect against hard drive failures by ensuring that files stored in shared folders= are automatically duplicated to multiple hard drives.
Benefits
Windows Home Server Drive Extender offers the following benefits for storage solutions. Some of the benefits are:
· = Allows the seamless addition of more = hard drives
As you add more hard drives to your home server, they are treated as=
a
single large pool of available storage space. You no longer need to deal wi=
th
drive letters (such as E:, F:, and G: ) because you can add more hard drive=
s.
· Wor= ks with internal and external hard drives
You can add internal or external (for example, USB 2.0 or FireWire) =
hard
drives to your home server to increase the available storage.
· Sha= red Folder Duplication
Windows Home Server Drive Extender supports reliability by duplicating designated shared folders. Important data is stored on separate hard drives, which pro= vides protection against hard-drive failure. Duplication is configurable for every shared folder—so a shared folder can have multiple copies with each c= opy stored on a separate hard drive.
· Mak= es hard drives and their content easy to move
It is easy to remove outda= ted hard drives. You can store the content on other hard drives in the system and re= move old or small hard drives.
Windows Home Server Drive Extender is different than and m= ore powerful than a redundant array of independent disks (RAID) in several ways= :
- You can use any hard drive, any time. You are not restricted to adding mor= e hard drives of the same type and size. When you want to grow your home server storage, you can buy and add any hard drive you like.
- Internal
and external hard drives can be used to grow your storage. No space in
your home computer case? No problem—plug in one or more hard dri=
ves
of your choice.
- Drive
removal is easy. After you have had your home server for awhile, you m=
ay
want to remove older, smaller hard drives and add new, larger hard dri=
ves
so that you can store more files.
This section explains how Windows Home Server Drive Ex= tender works.
Windows Home Server Console
The Windows Home Server Console enables you to configu= re the server storage and shared folders on your home server. The Server Storage tab allows you to view, add, and remove hard dri= ves on your home server. You can see the status of your server storage, and att= empt to repair hard drives that show a status of Unhealthy. You can also see a graphical representation of the t= otal disk-space usage on your home server.
![3D"4_WHS_SRVRSTOR_01"](3D"1WindowsHomeServerTechnicalBrief-DriveExtender_files/image009.jpg")
From the Windows Home Server Console you can add a new hard drive to your h=
ome
server by following a simple wizard. The amount of storage available to your
shared folders and home computer backups increases proportionally. The hard
drives you add can be internal or external (for example, USB 2.0 or FireWir=
e).
|
Hard drives are formatted before they are added to s= erver storage. Make sure that you back up any important files that are on the h= ard drive before you add it to server storage. Formatting a hard drive deletes all files on the hard drive.
Do not use USB 1.1. USB 1.1 is much slower= than USB 2.0. The home server performs slowly if you connect hard drives = to a USB 1.1 port. If you are using external hard drives, ensure that they are connected through USB 2.0 or IEEE 1394 (for example, FireWire). = USB 2.0 works best with one drive per controller. Performance suffers if multiple hard drives are connected to a single USB 2.0 controller. Using hubs= to connect multiple USB drives to a single controller has a negative impact = on system performance and is not recommended. |
|
The Server Storage pie chart shows the space used by S= hared Folders, duplication of selected Shared Folders, the Home Computer Backup database, and System files. T= he amount of space taken up by ‘System’ in the pie chart includes = volume shadow copies, files and folders in the Recycle Bin, as well as any files w= hich are stored on a home server outside of the Shared Folders or application folders.
![3D"important_dd"](3D"1WindowsHomeServerTechnicalBrief-DriveExtender_files/image012.gif")
Important <=
/p>
There is no reason for files to end up in the Recycle = Bin of your home server, unless you are inappropriately using your home server wit= h a monitor, mouse and keyboard attached. All administrative access to your home server should be done from a = home computer using the Windows Home Server Console.
Removing Hard Drives
If you want to remove a hard drive, there must be suff= icient storage space on your home server so that the data and files can be duplica= ted to the hard drive before you physically remove it from your home server sys= tem. If there is not enough storage space, you will lose file duplication for so= me shared folders or lose some files. The home server will provide adequate warnings to prevent you from losing files.
![3D"note_dd"](3D"1WindowsHomeServerTechnicalBrief-DriveExtender_files/image011.gif")
Note
A best practice is to add a new larger hard drive to y=
our
home server, prior to removing an older hard drive with less disk space.
Be sure to use the Windows H= ome Server Console to tell your home server that you want to remove your hard d= rive prior to physically removing it from your home server. The Remove a Hard Di= sk Wizard will list the files which your home server was not able to move off of the = hard drive being removed. The reason for the failure is also noted in a details = page which appears at the end of the wizard.
The process of removing a ha= rd drive takes time, so plan the removal when no one needs access to your home serve= r.
![3D"Remove](3D"1WindowsHomeServerTechnicalBrief-DriveExtender_files/image014.jpg")
Importan=
t
If you unplug an external hard drive prior to using the Windows Home Server Console to remove it, the drive will be listed as Missi= ng. In this case, you should immediately plug the hard drive back into your home server, and then follow the instructions in the Remove a Hard Drive Wizard = to safely remove it.
Hard Drive Partitioning
In a single hard-drive system, Windows Home Server is configured with a 20-gigabyte system partition for the Windows Home Server operating system, and the remainder of the primary hard drive is allocated = to the primary data partition. Each subsequent (or secondary) hard drive is lo= gically added to the data partition. It appears to the user as one large hard drive; however, these drives are considered to be part of the secondary data parti= tion. In reality, your home server consists of multiple hard drives of varying si= zes.
The primary data partition is used to store a unique e= ntry for each file. If a home server has more than one hard drive, these files become “tombstones.” Tombstones are NTFS file system reparse po= ints that Windows Home Server Drive Extender understands. They are tiny files th= at redirect to one or two “shadow” files on the hard drives that m= ake up the secondary data partition. The shadow files are where your data is re= ally stored. If folder duplication is enabled for a Shared Folder, there will be= two shadow files. If duplication is Off, there will be one shadow file.
Note
The primary data partition in a home server should be = as large as possible for two reasons: <= /span>
· You want to provide sufficient space to grow= the file table for all of the files that you will store on your home server.
· Windows Vista® and other home computer operating systems check to see = if there is adequate space on the primary data partition prior to starting a c= opy operation.
You can add additional internal and external hard driv= es to your home server if you need more storage space for your folders and files. There is no need to use equal capacity hard drives—Windows Home Server will add the additional capacity of the new hard drive to the availa= ble storage on your home server.
![3D"caution_dd"](3D"1WindowsHomeServerTechnicalBrief-DriveExtender_files/image010.gif")
Caution
It is highly recommended that you not use hardware RAI= D technologies for your home server. Recovering from hard-drive failures becomes increasin= gly complex when hardware RAID systems are used. The recommended and supported = approach is to use multiple hard drives that are configured as Just a Bunch of Disks= (JBOD).
Shared Folder Duplication
If your home server has multiple hard drives, Windows= Home Server Drive Extender will automatically choose a hard drive to store the files. You do not have to configure or manage this. In addition, if you have multiple hard drives, Windows Home Server helps provide protection against = hard-drive failures by ensuring that files stored in shared folders are automatically duplicated across multiple hard drives. Duplication is configurable per sha= red folder, so a given shared folder can have two copies, with each copy stored= on a separate hard drive. &n= bsp;
Note
Shared folders can be marked Unhealthy if there is insufficient disk space for folder duplication to succeed. If you are running low on storage space, you can temporarily disable Folder Duplica= tion on one or more of your shared folders until you add a new hard drive to your home server.
![3D"3_WHS_SHRDFLDR_01"](3D"1WindowsHomeServerTechnicalBrief-DriveExtender_files/image016.jpg")
When you display the properties of a shared folder on =
the Shared Folders<=
/span>
tab, the size displayed does not include duplicates if the
Caution <=
/p>
Windows Home Server automatically manages = the shared folders on your home server. Do not modify the underlying configuration of = the shared folders that Windows Home Server manages. Creating shared folders= or changing the access permissions outside of the Windows Home Server Console is not supported and may cause future system updates to fail.
To highlight how this works, consider this example.
- A new entry for this file is created in the file table on the primary data partition. On a home server with multiple hard drives, this is a “tombstone” file.
- The Windows Home Server Drive Extender file system filter creates a pointer (repar= se point) for the new file and determines onto which hard drive the photo should be stored. The tombstone is updated with the location of the ac= tual file. This file is known as the “master or primary shadow.”= ;
- If Folder Duplication is enable= d for the Photos shared folder,= the Windows Home Server Drive Extender migrator service creates a duplicate copy of the file and updates the tombstone file on the primary data partition = with the reparse point to include the second location of the shadow file. T= his file is known as the “alternate or secondary shadow.”
Importa=
nt
If Folder Dup= lication is enabled, a shared folder may be marked as Unhealthy if there is not enough room to store two copies of the shared folder contents on different hard drives. There must be two hard dri= ves with enough space to store the contents of the shared folder.
Caution <=
/p>
You can lose files if you re=
move a
hard drive. To safely remove a hard drive, click the Server Storage tab on the Windows Home Server Console=
. If
you do not have enough server storage space, Windows Home Server
warns you that you could lose files or file duplication as a consequence of
removing the hard drive.
Drive Extender Filter and Migrator Service
Windows Hom= e Server Drive Extender creates the illusion of having a very large primary data partition by migrating files to one or more secondary data partitions. To complete the illusion, Windows Home Server Drive Extender leaves a “tombstone” file on the primary data partition, so that the user still sees the file in its original location. For example, even though Samp= le.jpg is not really taking up space on the primary data partition, it shows up if= you type “dir” at a command prompt or open Windows Explorer from th= e primary data partition. These tombstones effectively act as symbolic links to the s= hadow files.
Importa=
nt
If you wa= nt to access files in shared folders, always access them through the shared folder name (\\server\SharedFolderName or \\localhost\SharedFolderName). If you browse the file system through administrator's desktop, you will discover multiple places where you might think your data is stored, but your data is likely stored elsewhere. Accessing \\server\SharedFolderName or \\localhost\SharedFolderN= ame from the administrator’s desktop ensures that you will find your file without a performance issue.
Do not use standard tools to manually create, delete, or change the properties of shar= ed folders. If you want to configure shared folders, use the Windows Home Ser= ver Console from your home computer.
Caution <=
/span>
Do not us= e Disk Manager. Windows Home&n= bsp;Server is a powerful system that automatically manages your hard drives for you. Almost any change that you make with Disk Manager will cause the storage system on your home server to fail, and = possibly result in data loss.
Every time = a new file is created, the Windows Home Server Drive Extender file system filter = immediately creates the file as a tombstone. The performance benefit to this approach is that the file is sent directly to a secondary data partition the first time= it is introduced to the home server.
The Windows= Home Server Drive Extender Migrator service has three major functions:
· To duplicate certain files
· To migrate files that are not already migrat= ed
· To manage the storage across the hard drives=
The filter is not always able to migrate files when they are added to the home server, but the Migrator service runs in the background, looking for files = to migrate. If a file is in a shared folder that is configured for duplication, the Migrator service selects a second hard drive to store an alternate shad= ow.
![](3D"1WindowsHomeServerTechnicalBrief-DriveExtender_files/image018.gif")
When creati= ng an alternate shadow, the Migrator service prefers to select a secondary data p= artition to maximize the free space on the primary data partition. If there is only = one secondary data partition (such as a home server that has only two hard drives), or if= all the secondary data partitions are full, the Migrator service will store an alternate shadow on the primary data partition. This means that the benefit= s of duplication are available even on systems with only two hard drives.
If a file a= lready has the correct number of shadow files, the Migrator service will keep the alternate shadow files up-to-date and copy the contents of the master shado= w to the alternate shadow(s) if the contents of the file change.
When the fi= lter intercepts a change to a duplicated file, it only writes the data to the ma= ster shadow. This simplifies the filter, and also offers a performance advantage= by allowing the change to complete without waiting for multiple disks to finish writing. The Migrator service detects the change to the file and attempts to duplicate the file. The Migrator service will not duplicate a file while it= is open. If an application tries to open a file while the Migrator service is duplicating it, the Migrator service will immediately release its handle to= the file, and the Open request from the application will succeed.
The Drive Extender Migrator service is=
run
under the following conditions:
·
Every
hour, or to be more specific – after resting an hour after the last
completion.
·
When
the Drive Extender Migrator service starts up – typically when you fi=
rst
turn on your home server.
·
When
a shared folder is added or removed using the Windows Home Server
Console’s Shared Folders tab.
·
When
duplication on a Shared Folder is turned on or off.
·
When
a hard drive is added to Server Storage using the Windows Home Server Conso=
le.
Th= e Magic of Tombstones
When a file= is migrated from the primary data partition to a secondary data partition, Win= dows Home Server Drive Extender leaves behind a tombstone file on the primary da= ta partition to make it appear as though the file is still located on that pri= mary data partition. The tombstone is an ordinary NTFS file, with the typical fi= le metadata such as file name, time stamps, security access control list, and = file size.
To make Win= dows Home Server Drive Extender transparent to applications, the apparent size o= f the file must be accurate, for example, a 4 MB picture must appear to have a si= ze of 4 MB. Clearly Windows Home Server Drive Extender could not live up to its name if the 4 MB picture actually consumed 4 MB of space on the primary hard drive. So Windows Home Server Drive Extender relies on the sparse file feat= ure of NTFS—when a file is sparse, regions of it can be emptied, freeing = the associated disk space. Windows Home Server Drive Extender makes every tombs= tone a sparse file and the entire file is emptied. Storing the metadata for a tombstone still requires 4 KB per file on the primary data partition (size = on disk) due to the cluster size of the hard drive.
Every shado= w file that is created has the same name as the tombstone file. This makes it easi= er to recover from drive failures and keeps the tombstone and shadow file name= s in synch if the tombstone is renamed. When the Windows Home Server Drive Exten= der filter receives a request to rename a tombstone, it renames all the shadows= at the same time. Marking a file for deletion when closing it also propagates = to all the shadow files, so deleting a tombstone immediately deletes all the shadow files for it.
Ba= lancing Storage
The Windows= Home Server Drive Extender Filter determines which hard drive to initially write= a file to. One goal of the algorithm the Filter uses is to keep related files together on the same hard drive. Copying music from a CD to a hard drive illustrates why this is important. If a single secondary hard drive failed,= it is more convenient to lose all the music from a few CDs and then re-copy th= ose CDs than to insert hundreds of CDs to re-create one track from each. One wa= y to achieve this is to ensure that a set of files created around the same time = are stored on the same secondary hard drive.
An obvious = method for choosing the secondary hard drive would be to use the one with the most spa= ce free, but that would result in sometimes alternating among secondary hard drives. Consider the CD scenario again. A moment ago, the second hard drive= had the most space available, so Track 1 of this CD was saved there. Now that t= he second hard drive has this new file on it, the third hard drive has the most room = to hold Track 2, but we would really prefer to store it on the second hard dri= ve with Track 1. Choosing the hard drive with the least available space is a good choice because the hard drive w= ith the least free space tends to remain the hard drive with the least free spa= ce for a long time, and the same secondary hard drive will be chosen.
The Drive E= xtender Migrator service uses the secondary data partitions with the most free spac= e to store the secondary or alternate shadows of new files. When Folder Duplication is enabled= , the Migrator service fills the secondary data partitions with the most free spa= ce, and uses the primary data partition as a last resort.
Another goa= l in selecting the secondary hard drive for a file is to ensure that migrated fi= les have room to grow. If a migrated file is later opened and data is added to = it, you need enough free space on the secondary hard drive to hold that new data. T= his suggests that there should be a buffer of free space remaining on the lowest-space secondary hard drive before placing a shadow file on it. The Drive Extender Migrator service= will attempt to keep a buffer of 10 GB on each hard drive and increase that buff= er to 20 GB of free space, by migrating files to other secondary hard drives t= hat have 20 GB or more free space available.
If all of t= he secondary hard drives are so full that there may not be room for existing shadow file= s to grow, the Migrator service may move some shadow files to the primary data partition or alert the user that the home server is running low on storage.= The Migrator service makes the appropriate updates to the tombstones whenever it moves a shadow from one secondary data partition to another or from a secon= dary data partition to the primary data partition.
NT= FS and Drive Extender
Every hard = drive and data partition that Windows Home Server Drive Extender manages, primary= or secondary, is an NTFS volume. Volume management technologies such as RAID (= where drives are combined below the file system layer) potentially result in a directory on one disk that points to a file on another disk. In this case, = the file can be lost if either disk fails. Being resilient to single drive fail= ure enables Windows Home Server Drive Extender to support external drives, interfaces including USB and IEEE 1394 (such as FireWire), and internal integrated device electronics (IDE) or Serial ATA hard drives.
When Window= s Home Server Drive Extender migrates a file, it creates the shadow with the same = name as the tombstone. To prevent name conflicts, Windows Home Server Drive Exte= nder puts every shadow file under the \DE directory, but it preserves the rest of the path. For instance, if Windows Home Server Drive Extender migrates \photos\poodles.jpg, the shadow file would have the path \DE\photos\poodles= .jpg. If the primary hard drive fails, the Migrator service can re-create the tombstones on a new primary hard drive by scanning the files on the seconda= ry hard drives. Continuing with the same example, if the Migrator service is re-cre= ating a new primary data partition, and it finds the file \DE\photos\poodles.jpg = on a secondary data partition, the Migrator service can create a tombstone file called \photos\poodles.jpg on the primary data partition and link it to that shadow file.
Windows Hom= e Server Drive Extender does nothing unique to the secondary data partitions or the files on them, which enables you to recover most of the lost data—eve= n in worst-case scenarios. If the home server fails completely, all the surviving drives can be attached to a computer that is not even running Windows Home Server Drive Extender, and you can copy the files from the drives to that computer. Because the files retain their original names and paths (under the \DE directory), the files can be used with no specific recovery steps.
Importa=
nt
Although this works as a disaster recovery method, moving a secondary hard drive bet= ween computers is not a recommended or supported use of Windows Home Server Drive Extender.
The following are known differences between Windows Home Server with Drive Exte= nder and the business editions of Windows Server. The Drive Extender functionality a= lters some of the core NTFS functionality that some people may use on file servers running Windows Server Standard and Enterprise editions. Please note the following differen= ces:
· Files on Windows Home Server shared folders which are encrypted with NTFS encryption or compressed with NTFS compression will not be migrated or duplicated.
· Files containing NTFS reparse-points or NTFS extended attributes are not supported on Windows Home Server shared folders= .
· NTFS Hard-links pointing to a file on Windows Home Server shared folders cannot be created.
Unhealthy and Missing Hard Drives
Windows Home Server runs CHKDSK once a da=
y on
all of the hard drives on the home server to look for potential issues. At =
the
end of a CHKDSK pass, a hard drive can be marked as Unhealthy in the home server console. If you select an unhealthy hard
drive and then click Repair, the Repair a Hard Drive Wizard starts. =
It
attempts to fix errors by doing the following:
<=
span
style=3D'mso-bookmark:_Toc170880570'>· =
Scanning the hard drive by using the CHKDSK utility to
verify the integrity of the hard drive. If the primary hard drive is marked=
Unhealthy, the user is asked to r=
eboot
the home server.
<=
span
style=3D'mso-bookmark:_Toc170880570'>· =
Correcting hard drive errors, if possible.
<= span style=3D'mso-bookmark:_Toc170880570'>· = Rebuilding shared folder duplications, if necessary.<= o:p>
The design = of Windows Home Server Drive Extender assumes that when a secondary hard drive becomes unavailable, it will eventually come back. Often the issue is as simple as = an unplugged cable. While the secondary hard drive is unavailable, Windows Home Server Drive Extender will not migrate new files to it. If the duplication fails or if the file is not duplicated, the filter cannot open the file, an= d it returns an appropriate error message.
Note<=
/p>
Internal ha= rd disks are recommended over external hard disks, as it is harder to inadvertently unplug or remove an internal hard disk.
You can use= the Windows Home Server Console to inform Windows Home Server Drive Extender th= at a missing hard drive will never be used again by using the Remove a Hard Drive wizard. The Migrator service will enter a special repair mode, and it will inspect every tombstone file. If the tombs= tone had an alternate shadow on the missing hard drive, that link is removed from the reparse point on the tombstone. The Migrator service attempts to make an extra copy, so the file is duplicated again. If the master shadow was on the missing hard drive, the most recent alternate shadow is promoted to become = the master shadow. I a file was not duplicated and the only shadow copy of the = data was on the missing hard drive, that data is lost. The Migrator service still has work to do because a file with no remaining shadow files cannot be open= ed or deleted. If the Migrator service left the tombstone alone, it would cont= inue to appear in the directory, and the user would have no easy method for dele= ting it. While in repair mode, when the Migrator service finds a tombstone file = for which the only shadow was on a permanently missing hard drive, the Migrator= service deletes the tombstone.
File Conflict Notifications =
Windows Hom= e Server proactively checks the health of all files stored in the shared folders dur= ing a migration pass. If any issues are discovered, a yellow health notification will be issued containing a detailed conflict reason for each file. =
Files on Windows Home Server cannot be migrated or duplicated while in-use by oth= er applications that are running on Windows Home Server or on a home computer accessing files on the home server. One of the primary reasons for file conflicts is caused by files that remain open for more than 24 hours; these are reported with a conflict of “File is open” as the Migrator service needs the files to be cl= osed to allow migration or duplication to occur. Please close any open files to enable the Migrator service to work properly.
For more information about other types of file conflicts, see the Microsoft Web site at http://go.microsoft.com/fwlink/?LinkId=3D119695
Following a= re a few additional tips and techniques for situations that you may run into with Windows Home Server Server Storage after upgrading to Windows Home Server P= ower Pack 1.
Vi= ewing Orphan Shadow Files
Windows Hom= e Server with Power Pack 1 proactively searches for orphan shadows on home server ha= rd drives, and places them in an application folder on the primary data partition. Orphan shadows cou= ld get created when hard drives appeared as ‘missing’ on home server s= ystems running the initial release of Windows Home Server. Orphan shadows are secondary copie= s of files stored in shared folders and in certain circumstances these shadow fi= les may not have been properly cleaned up when hard drives went ‘missing’.
The special location above will maintain the folder structure of the original f= ile which allows the user to understand in which Shared Folder the original file was stored.
![](3D"1WindowsHomeServerTechnicalBrief-DriveExtender_files/image003.gif")
=
To view any orphan
shadow files
1.&n= bsp; Run mstsc.exe to start a Remote Desktop Connection session to your home server.
![3D"caution_dd"](3D"1WindowsHomeServerTechnicalBrief-DriveExtender_files/image019.gif")
Caution
Be careful when using a Remote Desktop
Connection to your home server. You can damage Windows Home Server
functionality if you use it incorrectly.
2.&n= bsp; O= pen Windows Explorer and navigate to = D:\folders\{1618D36B-F4E7-4360-B070-A= 32070519DC9}\
Di= sabling Volume ShadowCopy Services
The initial= release of Windows Home Server used Volume ShadowCopy Services to support Previous Versions functionality for files stored in Shared Folders on the home serve= r. Windows Home Server triggered a snapshot every 12 hours, enabling users to access previous versions of files stored in Shared Folders on a home server, through the Previous Versions functionality available in some Windows client operating system editions.
The new med= ia editions of Windows Home Server Power Pack 1 ship with Volume ShadowCopy Services for home server Shared Folders turned off. If you purchased the initial versi= on of Windows Home Server and upgraded to Power Pack 1, then this feature is stil= l turned on and may take up considerable storage space on your home server. The amount of space taken up by ‘System’ in the Server Storage pie chart includes the space use= d by volume shadow copies, which in some cases can be significant.
=
Disabling Volume
ShadowCopy Services and reclaiming the disk space
1.&n= bsp; Run mstsc.exe to start a Remote Desktop Connection session to your home server.
Caution =
Be careful when using a Remote Desktop
Connection to your home server. You can damage Windows Home Server
functionality if you use it incorrectly.
2.&n=
bsp;
O=
pen a
Command Prompt, Click Start, Run and type CMD
3.&n=
bsp;
To
delete all of the existing volume shadow copy snapshots and reclaim the disk
space used by the snapshots, type =
vssadmin
delete shadows /all
4.&n=
bsp;
To
disable the Windows Home Server storage manager service from taking future
snapshots, type regedit
5.&n=
bsp;
N=
avigate
to
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Home Server\Storage
Manager\Volumes.
6.&n=
bsp;
F=
ind a
sub key which has a MountPoint value
equal to D:
7.&n=
bsp;
U=
nder
that key set the value of SnapPeri=
od to 0
For more information about Windows Home Ser= ver, see the Microsoft Web site at http://go.microsoft.com/fwlink/?LinkId= =3D100260.
For more information about Windows Home Server Drive Extender, see the Community For= ums at: http://go.microsoft.com/fwlink= /?LinkId=3D100263.