Windows 7 Resource Kit- P14

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If you do not configure this policy setting, the system limits the space that offline files occupy to 25 percent of the total space on the drive where the Offline Files cache is located . The limit for automatically cached files is 100 percent of the total disk space limit . However, the users can change these values using the Offline Files Control Panel tool . If you enable this setting and specify a total size limit greater than the size of the drive hosting the Offline Files cache and that drive is the system drive, the total size limit...

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If you do not configure this policy setting, the system limits the space that offline files occupy to 25 percent of the total space on the drive where the Offline Files cache is located . The limit for automatically cached files is 100 percent of the total disk space limit . However, the users can change these values using the Offline Files Control Panel tool . If you enable this setting and specify a total size limit greater than the size of the drive hosting the Offline Files cache and that drive is the system drive, the total size limit is automatically adjusted downward to 75 percent of the size of the drive . If the cache is located on a drive other than the system drive, the limit is automatically adjusted downward to 100 percent of the size of the drive . If you enable this setting and specify a total size limit less than the amount of space currently used by the Offline Files cache, the total size limit is automatically adjusted upward to the amount of space currently used by offline files . The cache is then con- sidered full . If you enable this setting and specify an auto-cached space limit greater than the total size limit, the auto-cached limit is automatically adjusted downward to equal the total size limit . note The Limit Disk Space Used By Offline Files policy setting replaces the Default Cache Size policy setting used by earlier versions of Windows. n Turn On Economical Application Of Administratively Assigned Offline Files This policy setting allows you to turn on economical application of administratively assigned Offline Files . If you enable this policy setting, only new files and folders in administratively assigned folders are synchronized at logon . Files and folders that are already available offline are skipped and are synchronized later . If you disable or do not configure this policy setting, all administratively assigned folders are synchronized at logon . aDDITIONaL OFFLINE FILES pOLICY SETTINGS FOR WINDOWS 7 The following Group Policy settings for managing Offline Files are new in Windows 7: n Configure Background Sync This policy setting applies to any user who logs on to the specified machine while this policy is in effect . This policy is in effect when a net- work folder is determined by the Configure Slow-Link Mode policy to be in slow-link mode . For network folders in slow-link mode, a sync will be initiated in the background on a regular basis, according to these settings, to synchronize the files in those shares/fold- ers between the client and server . By default, network folders in slow-link mode will be synchronized with the server every 360 minutes, with the start of the sync varying between 0 and 60 additional minutes (as shown in Figure 15-18) . Working with Offline Files CHapTER 15 603 Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
FIgURE 15-18 The new Configure Background Sync policy setting in Windows 7 You can override the default sync interval and variance by setting Sync Interval and Sync Variance values . You can also set a period of time in which background sync is disabled by setting Blockout Start Time and Blockout Duration values . To ensure that all the network folders on the machine are synchronized with the server on a regular basis, you may also set the Maximum Allowed Time Without A Sync value . You may also configure Background Sync for network shares that are in user-selected Work Offline mode . This mode is in effect when a user selects the Work Offline option for a specific share . When selected, all configured settings will apply to shares in user- selected Work Offline mode as well . n Enable Transparent Caching Enabling this policy optimizes subsequent reads to network files by a user or an application . This is done by caching reads to remote files over a slow network in the Offline Files cache . Subsequent reads to the same file are then satisfied from the client after verifying the integrity of the cached copy . This policy not only improves user response times but also decreases bandwidth consumption over the WAN links to the server . The cached files are temporary and are not available to the user when offline . The cached files are not kept in sync with the version on the server, and the most current version from the server is always available for subsequent reads . This policy is triggered by the configured round-trip network latency value (shown in Figure 15-19) . We recommend using this policy when the network connection to the server is slow . For example, you can configure a value of 60 milliseconds as the round- trip latency of the network above which files should be transparently cached in the Offline Files cache . If the round-trip latency of the network is less than 60 milliseconds, reads to remote files will not be cached . If you do not configure this setting, remote files will not be transparently cached on user clients . 604 CHapTER 15 Managing Users and User Data Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
FIgURE 15-19 The new Enable Transparent Caching policy setting in Windows 7 n Exclude Files From Being Cached This policy enables administrators to exclude certain file types from being made available offline . You need to specify the file exten- sions of the file types that should be excluded (shown in Figure 15-20) . A user then will be unable to create a file of this type in the folders that are available offline . FIgURE 15-20 The new Exclude Files From Being Cached policy setting in Windows 7 Working with Offline Files CHapTER 15 605 Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
diReCt FRoM tHe SoURCe Troubleshooting Roaming User Profile Folder Redirection, and Client-Side Caching Issues in Windows Vista and later Versions paul D. LeBlanc, Manager Supportability Program T he following lists describe some common support issues with Folder Redirection, RUp, and CSC in Windows Vista and later versions. Roaming User Profile Issue Troubleshooting Symptom: Loading temporary profile error during user logon: “Windows cannot find the local profile and is logging you on with a temporary profile. Changes you make to this profile will be lost when you log off.” n possible cause #1: SID in profileList structure deleted Explanation: Microsoft does not recommend that you delete user profiles using anything other than the Control panel item (Computer properties \advanced System Settings\User profiles\Settings). When the folder structure for a user profile is deleted using Windows Explorer or the command prompt, the corresponding registry entries under the profileList registry key are left behind. Resolution: Remove the corresponding SID entry under the profileList registry key: HKEY_LOCaL_MaCHINE\Software\Microsoft\Windows NT\CurrentVersion \profileList. n possible cause #2: User in Guests group Explanation: During logon, the interactive user is checked for membership in the local Guests group and the domain Guest group (if the user is the mem- ber of a domain). Resolution: If appropriate, remove the affected user from the local Guests /Domain Guest membership (see http://support.microsoft.com/kb/940453). n possible cause #3: Insufficient permissions (roaming profile) Explanation: If permissions have been altered on a working roaming profile, the user may encounter this error. Resolution: Correct the permissions so that the user has Full Control over her Roaming User profile folders. If a locked-down user profile is required, use a mandatory user profile. 606 CHapTER 15 Managing Users and User Data Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
Folder Redirection Troubleshooting Symptom: Duplicate folders in user profile n possible cause #1: partial sync Explanation: Users of Windows Vista and later versions can select various folders within their user profiles to redirect to a local or remote drive. If only some of the contents of a folder are moved, the user may see multiple folders under a user profile, such as two folders named Documents or Music. Resolution: allow the session to complete data transfer before logoff. n possible cause #2: Local and remote copies of files kept Explanation: When a user’s folder is being redirected, the user will be asked whether she wants to move all current content. If the user chooses not to move the contents but only to copy them, duplicate folders will appear under the user profile—one local, one remote. Resolution: This is by design. n possible cause #3: program creating folder locally (application compatibility) Explanation: after a user redirects a user profile folder or folders successfully, on running an application, a local instance of the user profile folder(s) may be created. This behavior is due to the application using only local resources or having a fixed path for resources and not using the environment variables. This is an application-specific issue. Resolution: Update the application or do not redirect the affected user profile folder(s). Client-Side Caching Troubleshooting Symptom: Files/folders not seen while offline n possible cause #1: Sync has not completed (because it occurs during background) Explanation: This is a fundamental change from Windows Xp. In Windows Vista and later versions, Offline Files will synchronize in the background as user activity allows. This means that users will not have to wait for files to synchronize before completing a logoff. However, this also means that, depending on the volume and type of data that is to be synchronized, synchronization may need further logon sessions to complete. Resolution: allow longer logon sessions for larger amounts of data to be synchronized. Working with Offline Files CHapTER 15 607 Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
n possible cause #2: Sync has not completed Explanation: another possible root cause of incomplete synchronization is the same as in Windows Xp—namely, if a file is in use, open file handles will prevent the file from synchronizing. Resolution: This is an unchanged behavior and is by design. n possible cause #3: Offline files respond slowly over a VpN connection Explanation: On computers running Windows Vista and later versions, you experience slow performance after you establish a VpN connection. additionally, it may take several minutes to open a redirected shell folder. This problem occurs if the following conditions are true: • Offline files are enabled on the computer. • Some offline files are cached on the local computer. • You logged on to the computer when you were offline. • The VpN connection is based on a slow connection. This problem usually lasts several minutes and then disappears. Resolution: See http://support.microsoft.com/kb/934202. (This issue has been fixed in Sp1.) n possible cause #4: Changes to an offline file are not saved to the server when files are synchronized Explanation: When you modify an offline file in Windows Vista and later versions, the changes are not saved to the server when files are synchronized. When this problem occurs, you receive the following error message: “access Denied.” additionally, a .tmp file that corresponds to the file appears on the server. You may experience this symptom even when you have Change per- missions to the shared resource. Resolution: See http://support.microsoft.com/kb/935663. (This issue has been fixed in Sp1.) Summary Folder Redirection, Offline Files, and Roaming User Profiles have been enhanced in Windows 7 to provide better support for corporate roaming scenarios and high availability for file server scenarios . You can implement these features using the procedures outlined in this chapter; you can manage various aspects of their behavior using Group Policy and from the user interface . 608 CHapTER 15 Managing Users and User Data Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
Additional Resources These resources contain additional information and tools related to this chapter . Related Information n “Folder Redirection Overview” found at http://technet.microsoft.com/en-us/library /cc732275.aspx. n “File Sharing and Offline Files Enhancements” found at http://technet.microsoft.com /en-us/library/dd637828.aspx. n “Windows Browse and Organize Features” found at http://technet.microsoft.com /en-us/library/dd744693.aspx. n Managing Roaming User Data Deployment Guide found at http://technet.microsoft.com /en-us/library/cc766489.aspx . Note that this information is for Windows Vista, so check first to see whether this topic has been updated for Windows 7 either here or else- where on TechNet . On the Companion Media n AddLocalUserToLocalGroup .ps1 n Change-LocalUserPassword .ps1 n CreateLocalGroup .ps1 n CreateLocalUser .ps1 n Remove-LocalUserFromLocalGroup .ps1 n Get-LocalGroupMembers .ps1 n LocateDisabledUsers .ps1 n Get-LocalGroups .ps1 n Get-LocalUsers .ps1 n LocateLockedOutLocalUsers .ps1 n ListUserLastLogon .ps1 n FindAdmin .ps1 n EnableDisableUser .ps1 n BackupFolderToServer .ps1 n GetSystemRestoreSettings .ps1 Additional Resources CHapTER 15 609 Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
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CHAPTER 16 Managing Disks and File Systems n Overview of Partitioning Disks 612 n Working with Volumes 615 n File System Fragmentation 622 n Backup And Restore 624 n Windows ReadyBoost 639 n BitLocker Drive Encryption 641 n Encrypting File System 662 n Symbolic Links 664 n Disk Quotas 670 n Disk Tools 673 n Summary 677 n Additional Resources 678 T he most important aspect of a computer is the user data . Businesses depend on the privacy of their intellectual property to stay competitive, and government organi- zations depend on confidentiality for national security . Thus, it’s critical that Windows protects the availability, integrity, and privacy of the user data on client computers . The Windows 7 operating system provides several important improvements to disk and file management . Windows 7 includes several improvements that both users and administrators will appreciate . By default, backups automatically create a System Image backup of the entire system drive . Additionally, you can store System Image backups to shared folders . System Image backups greatly reduce the time required to restore a computer after a hard disk failure or system corruption . To improve data security, you can use Windows BitLocker Drive Encryption to encrypt an entire volume, protecting the data on the disk even if the disk is physically removed 611 Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
from the computer . BitLocker works alongside Encrypting File System (EFS): BitLocker can encrypt system files and the page file along with any other files on the volume, whereas EFS is intended primarily to encrypt user files . Windows 7 supports BitLocker To Go, enabling removable flash drives to be encrypted with BitLocker . The BitLocker To Go Reader enables earlier versions of Windows to read encrypted files from the removable flash drive if the user has the required password . This chapter describes these features, as well as features introduced in Windows Vista, in more detail . Overview of Partitioning Disks Before you can format disks into volumes that applications can access, you must partition them . Windows 7 provides flexible partitioning that you can change even after you have formatted a volume . However, it’s still important to plan ahead when creating partitions for features such as BitLocker Drive Encryption, which has very specific partitioning requirements . note If Windows discovers a problem with a volume, it might schedule ChkDsk to run the next time the computer starts. Large volumes, especially volumes bigger than a terabyte, can take a very long time to check—more than an hour. During this time, the computer will be offline. Therefore, when you plan the size of your partitions, consider the time required for Windows to perform a ChkDsk operation at startup. The sections that follow describe how to partition disks in Windows 7 . How to Choose Between MBR or GpT Master Boot Record (MBR) and Globally Unique Identifier Partition Table (GPT) are two dif- ferent disk-partitioning systems . MBR is the most common system and is supported by every version of Windows, including Windows Vista and Windows 7 . GPT is an updated and im- proved partitioning system and is supported on Windows Vista, Windows 7, Windows Server 2008, and 64-bit versions of Windows XP and Windows Server 2003 operating systems . GPT offers several advantages over MBR: n In Windows, GPT can support up to 128 partitions . MBR supports only four partitions . n GPT accurately describes physical disk geometry, allowing Windows to create partitions and logical drives on cylinder boundaries . Although Windows attempts to do this for MBR, the geometry that MBR reports has no relationship to a modern drive’s physi- cal geometry because it has been altered to enable larger capacities . Different disk vendors have created vendor-specific workarounds for this problem that are difficult to manage . Therefore, partitioning is more reliable when using GPT . 612 CHapTER 16 Managing Disks and File Systems Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
n GPT can support larger partition sizes . In theory, a GPT disk can be up to 18 exabytes in size (about 18,000,000 terabytes) . n GPT uses primary and backup partition tables for redundancy and CRC32 fields for improved partition data structure integrity . MBR does not have redundant partition tables . note all GpT disks start with a protective MBR partition to prevent previously released MBR disk tools, such as Microsoft MS-DOS FDISK or Microsoft Windows NT Disk adminis- trator, from damaging the GpT partition because they don’t recognize the partition type. If you mount an MBR disk in a 32-bit version of Windows Xp, it will see only the protective MBR partition. To boot from a GPT disk, the computer must support the Extensible Firmware Interface (EFI) . Basic input/output system (BIOS)–based systems must boot from an MBR disk, although they can use a second GPT disk as a data disk . All removable media must use MBR . MoRe inFo For more information about GpT, read the “Windows and GpT FaQ” at http://www.microsoft.com/whdc/device/storage/GPT_FAQ.mspx. Converting from MBR to GpT Disks You can convert disks only from MBR to GPT, or vice versa, if the disk does not contain parti- tions or volumes . You can convert a disk in two ways: n In the Disk Management snap-in, right-click the MBR drive you want to convert to GPT and then click Convert To GPT Disk . If the drive is not empty or contains partitions, this option is unavailable . n In the DiskPart command-line tool, select the drive you want to convert and run the command convert gpt . Similarly, to convert from GPT to MBR, run the command convert mbr . note When a dynamic disk is converted between MBR and GpT types, it must first be converted to a basic disk, then converted to MBR or GpT as appropriate, and then convert- ed back to a dynamic disk. When you use the Disk Management snap-in, the conversion to a basic disk and then back to a dynamic disk happens automatically in the background. If you’re using the command-line Diskpart tool, you must explicitly make the conversions. Overview of Partitioning Disks CHapTER 16 613 Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
GpT partitions For EFI computers that boot from a GPT disk, the boot disk must contain at least the following partitions: n EFI System Partition On EFI computers, the EFI System Partition (ESP) is about 100 megabytes (MB) and contains the Windows Boot Manager files . For more information about startup files, read Chapter 29, “Configuring Startup and Troubleshooting Startup Issues .” The ESP has the following partition globally unique identifier (GUID): DEFINE_GUID (PARTITION_SYSTEM_GUID, 0xC12A7328L, 0xF81F, 0x11D2, 0xBA, 0x4B, 0x00, 0xA0, 0xC9, 0x3E, 0xC9, 0x3B) n Microsoft Reserved Partition The Microsoft Reserved Partition (MSR) reserves space on each disk drive for subsequent use by operating system software . On drives smaller than 16 gigabytes (GB), the MSR is 32 MB . On drives 16 GB or larger, the MSR is 128 MB . GPT disks do not allow hidden sectors . Software features that formerly used hidden sectors now allocate portions of the MSR for feature-specific partitions . For example, converting a basic disk to a dynamic disk causes the MSR on that disk to be reduced in size, and a newly created partition holds the dynamic disk database . The MSR has the following partition GUID: DEFINE_GUID (PARTITION_MSFT_RESERVED_GUID, 0xE3C9E316L, 0x0B5C, 0x4DB8, 0x81, 0x7D, 0xF9, 0x2D, 0xF0, 0x02, 0x15, 0xAE) n Data partition This partition stores Windows 7 system files and user files . The data partition has the following partition GUID: DEFINE_GUID (PARTITION_BASIC_DATA_GUID, 0xEBD0A0A2L, 0xB9E5, 0x4433, 0x87, 0xC0, 0x68, 0xB6, 0xB7, 0x26, 0x99, 0xC7); Additionally, dynamic disks can use two different GPT partitions: n A data container partition corresponding to the MBR partition 0x42, with the following GUID: DEFINE_GUID (PARTITION_LDM_DATA_GUID, 0xAF9B60A0L, 0x1431, 0x4F62, 0xBC, 0x68, 0x33, 0x11, 0x71, 0x4A, 0x69, 0xAD); n A partition to contain the dynamic configuration database with the following GUID: DEFINE_GUID(PARTITION_LDM_METADATA_GUID, 0x5808C8AAL, 0x7E8F, 0x42E0, 0x85, 0xD2, 0xE1, 0xE9, 0x04, 0x34, 0xCF, 0xB3); Data disks (non-boot disks) must have an MSR and a data partition . Standard users will typically see only the data partitions; however, the other partitions will be visible to adminis- trators using the Disk Management snap-in or the DiskPart tool . 614 CHapTER 16 Managing Disks and File Systems Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
Choosing Basic or Dynamic Disks Traditional hard disks are called basic disks in Windows Vista and Windows 7, and they have the same functionality that basic disks have always had, plus a few extras . You can create new partitions (called simple volumes in Windows Vista and Windows 7), delete partitions, and extend or shrink the existing partitions . The ability to extend or shrink an existing partition is an important new feature in Windows Vista and continues to be supported in Windows 7 . Dynamic disks, first introduced in Microsoft Windows 2000, provide all of the functionality of the basic disk, plus the ability to span a volume across multiple dynamic disks or stripe multiple dynamic disks to create a larger (and faster) volume . Dynamic disks present difficulties, however, because they are not accessible from operating systems other than the operating system instance that converted the disk to dynamic . This makes dynamic disks inaccessible in multiboot environments and makes recovering data more difficult in the event of partial hard disk failure . You should always use basic disks unless you have a specific requirement that can be met only by dynamic disks . Working with Volumes In earlier versions of Windows, your choices for resizing volumes and partitions after they have been created are limited . If you need to add space to a volume, your only choice is to make the disk a dynamic disk and then create a spanned volume . If you want to expand or contract a partition, your only choice is to use third-party tools . In Windows Vista and Windows 7, however, you can now expand and contract volumes without data loss and with- out requiring a reboot . How to Create a Simple Volume In Windows Vista and Windows 7, the term simple volume has been expanded to include both partitions on basic disks and simple volumes on dynamic disks . If your only need is a simple volume, your best choice is a basic disk because a simple volume doesn’t use the advanced features of a dynamic disk . To create a simple volume, open the Disk Management snap-in and follow these steps: 1. Right-click an unallocated space on one of the disks and then click New Simple Volume . The New Simple Volume Wizard appears . 2. Click Next . On the Specify Volume Size page, enter the size of volume you want to cre- ate in megabytes . The default is the maximum space available on the disk . Click Next . 3. On the Assign Drive Letter Or Path page, assign a drive letter or mount point . Click Next . 4. On the Format Partition page, choose the formatting options for the volume and then click Next . 5. Click Finish on the summary page of the wizard and the volume will be created and formatted according to your selections . Working with Volumes CHapTER 16 615 Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
note The Disk Management snap-in always creates simple volumes on dynamic disks or primary partitions on basic GpT disks. For basic MBR disks, the first three volumes created will be primary partitions. The fourth simple volume on a basic MBR disk is created as an extended partition and a logical drive. Further simple volumes on the basic MBR disk are logical drives. Creating simple volumes using the command line or a script requires that you know whether the disk you’re creating the volume on is a dynamic or basic disk . The DiskPart tool is not as flexible as the Disk Management snap-in, which automatically adjusts to create either a volume or a partition depending on the disk type . With DiskPart, you must create a partition on a basic disk and a volume on a dynamic disk . How to Create a Spanned Volume A spanned volume uses the free space on more than one physical hard disk to create a bigger volume . The portions of disk used to create the volume do not need to be the same size and can actually include more than one free space on a disk . A spanned volume provides no ad- ditional speed benefits and increases the risk of catastrophic failure leading to data loss . The failure of any disk involved in the spanned volume will make the entire volume unavailable . note To achieve a speed benefit with multiple disks, you must use striping, such as that provided by RaID 1 or RaID 5. With striping, every file on a volume is evenly distributed between multiple physical disks. With striping, files can be read from or written to multiple disks simultaneously, increasing throughput. Spanning simply appends one disk to the next, so any given file is probably stored only on a single disk. The best way to add striping is to use a computer or add-on card that supports hardware RaID. If you still want to create a spanned volume, follow these steps: 1. Open the Disk Management snap-in . 2. Right-click a free-space segment that you want to include in the spanned volume and then select New Spanned Volume from the shortcut menu . The New Spanned Volume Wizard appears . 3. Click Next . On the Select Disks page, select from the available disks and then click Add to add the disks to the spanned volume . Select each disk in the Selected column and set the amount of space to use on that disk for the spanned volume . Click Next . 4. On the Assign Drive Letter Or Path page, the default is to assign the next available drive letter to the new volume . You can also mount the volume on an empty NTFS folder on an existing volume . Click Next . 616 CHapTER 16 Managing Disks and File Systems Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
5. On the Format Volume page, choose the formatting options for the new volume . Windows Vista and Windows 7 support only NTFS formatting from the Disk Management snap-in . To format with FAT or FAT32, you need to use the command line . Click Next . 6. Click Finish on the summary page to create the volume . Creating a spanned volume using DiskPart is a somewhat more complicated process than creating a simple volume . You can’t just create the spanned volume in one step; you need to first make sure that the disks to be used are converted to dynamic . Then you create a simple volume on the first disk of the spanned volume, extend the volume to the second disk, and then add any additional disks involved in the span . Finally, you must assign the volume to a drive letter or mount point . How to Create a Striped Volume A striped volume uses the free space on more than one physical hard disk to create a bigger volume . Unlike a spanned volume, however, a striped volume writes across all volumes in the stripe in small blocks, distributing the load across the disks in the volume . The portions of disk used to create the volume need to be the same size; the size of the smallest free space included in the striped volume will be the determinant . A striped volume is faster than a simple volume because reads and writes happen across multiple disks at the same time . However, this additional speed comes with an increased risk of catastrophic failure leading to data loss when compared to a volume residing on a single physical disk because the failure of any disk involved in the spanned volume will make the entire volume unavailable . Therefore, it is critical to regularly back up striped volumes . To create a striped volume, follow these steps: 1. Open the Disk Management snap-in . 2. Right-click a free-space segment that you want to include in the striped volume and then click New Striped Volume . The New Striped Volume Wizard appears . 3. Click Next . On the Select Disks page, select from the available disks and then click Add to add the disks to the striped volume . Set the amount of space to use on the disks for the striped volume . Click Next . 4. On the Assign Drive Letter Or Path page, the default is to assign the next available drive letter to the new volume . You can also mount the volume on an empty NTFS folder on an existing volume . Click Next . 5. On the Format Volume page of the New Striped Volume Wizard, choose the format- ting options for the new volume . Windows Vista and Windows 7 support only NTFS formatting from the Disk Management snap-in . To format with FAT or FAT32, you need to use the command line . Click Next . 6. Click Finish on the summary page to create the volume . If the disks are basic disks, you’ll be warned that this operation will convert them to dynamic disks . Click Yes to convert the disks and create the striped volume . Working with Volumes CHapTER 16 617 Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
How to Resize a Volume New in Windows Vista, and also included in Windows 7, is the ability to expand and contract simple volumes without a third-party tool . You can also expand and contract spanned vol- umes, but striped volumes are fixed in size . To change the size of a striped volume, you need to delete and re-create it . note Third-party products offer additional flexibility in resizing partitions, allowing the resizing of partitions with no available unallocated space immediately adjacent to the partition that you want to extend and also allowing you to control the placement of the unallocated space after shrinking the partition. To shrink a volume, follow these steps: 1. Open the Disk Management snap-in . 2. Right-click the volume you want to shrink and then click Shrink Volume . 3. The Shrink dialog box opens and shows the maximum amount by which you can shrink the volume in megabytes . If desired, decrease the amount to shrink the volume and then click Shrink . The shrink process will proceed without further prompting . You can also use DiskPart interactively from an elevated command line, using exactly the same steps as you would use with a script . The following interactive steps show how to shrink a volume as much as possible . DiskPart Microsoft DiskPart version 6.1.7100 Copyright (C) 1999-2008 Microsoft Corporation. On computer: WIN7 DISKPART> list volume Volume ### Ltr Label Fs Type Size Status Info ---------- --- ----------- ----- ---------- ------- --------- -------- Volume 0 F New Volume NTFS Simple 20 GB Healthy Volume 1 E New Volume NTFS Simple 40 GB Healthy Volume 2 R DVD-ROM 0 B No Media Volume 3 C NTFS Partition 75 GB Healthy System Volume 4 D New Volume NTFS Partition 52 GB Healthy DISKPART> select volume 4 Volume 4 is the selected volume. 618 CHapTER 16 Managing Disks and File Systems Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
DISKPART> shrink querymax The maximum number of reclaimable bytes is: 26 GB DISKPART> shrink DiskPart successfully shrunk the volume by: 26 GB note In the code list, the command shrink querymax queries the volume to determine the maximum amount of shrinkage that the volume will support. The actual number will depend on the amount of free space on the volume, the fragmentation level, and where critical files are located on the volume. To extend a volume, the steps are similar: 1. Open the Disk Management snap-in . 2. Right-click the volume you want to extend and then click Extend Volume . The Extend Volume Wizard appears . 3. Click Next . The Select Disks page appears . 4. Select the disks and set the amount of space from each disk to include in the extended volume . If you are extending a volume on a basic disk and you choose noncontiguous unallocated space or space on a second disk, the extension will also convert any disks involved to dynamic disks as part of the extension . Click Next . 5. On the Completing The Extend Volume Wizard page, click Finish . If the extension requires conversion to a dynamic disk, you’ll see a warning . How to Delete a Volume You can delete a volume from either the Disk Management snap-in or the command line . Deleting a volume permanently erases the data stored on the volume . From the Disk Management snap-in, simply right-click the volume and then click Delete Volume . From the DiskPart command-line tool at an elevated command prompt, select the volume and then use the delete volume command, as the following code demonstrates . DiskPart Microsoft DiskPart version 6.1.7100 Copyright (C) 1999-2008 Microsoft Corporation. On computer: WIN7 DISKPART> list volume Working with Volumes CHapTER 16 619 Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
Volume ### Ltr Label Fs Type Size Status Info ---------- --- ----------- ----- ---------- ------- --------- -------- Volume 0 F New Volume NTFS Simple 20 GB Healthy Volume 1 E New Volume NTFS Simple 40 GB Healthy Volume 2 R DVD-ROM 0 B No Media Volume 3 C NTFS Partition 75 GB Healthy System Volume 4 D New Volume NTFS Partition 52 GB Healthy DISKPART> select volume 0 Volume 0 is the selected volume. DISKPART> delete volume DiskPart successfully deleted the volume. How to Create and Use a Virtual Hard Disk Virtual hard disks (VHDs) are a file type that acts like a hard disk . In previous versions of Windows, VHDs were used by virtual machines, such as those created by Microsoft Virtual Server 2005 or Microsoft Virtual PC . Additionally, Complete PC Backup in Windows Vista created a copy of the computer’s hard disk as a VHD disk image . Beginning with Windows 7, you can now mount VHDs exactly like a physical disk . By mounting a VHD, you can easily copy files to and from the virtual disk . Additionally, Windows 7 can be configured to boot from a VHD, as described in Chapter 29 . You can create a VHD from either the Disk Management snap-in or the command line . After you create the VHD, you must attach it and then format it before you can use it, just like a physical partition . From the Disk Management console, following these steps: 1. Right-click Disk Management and then click Create VHD . Follow the prompts that appear . 2. Right-click the new disk and then click Initialize Disk . Click OK . 3. Right-click the new disk and then click New Simple Volume (or select a different volume type, if available) . Follow the prompts that appear . The new virtual disk is ready to be used, just like any other disk . From the DiskPart command-line tool at an elevated command prompt, run the create vdisk command and specify the file (to name the file) and maximum (to set the maximum size in megabytes) parameters . The following code demonstrates how to create a VHD file at C:\vdisks\disk1 .vdh with a maximum file size of 16 GB (or 16,000 MB) . 620 CHapTER 16 Managing Disks and File Systems Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
DiskPart Microsoft DiskPart version 6.1.7100 Copyright (C) 1999-2008 Microsoft Corporation. On computer: WIN7 DISKPART> create vdisk file="C:\vdisks\disk1.vhd" maximum=16000 Volume ### Ltr Label Fs Type Size Status Info ---------- --- ----------- ----- ---------- ------- --------- -------- Volume 0 F New Volume NTFS Simple 20 GB Healthy Volume 1 E New Volume NTFS Simple 40 GB Healthy Volume 2 R DVD-ROM 0 B No Media Volume 3 C NTFS Partition 75 GB Healthy System Volume 4 D New Volume NTFS Partition 52 GB Healthy DISKPART> select volume 0 Volume 0 is the selected volume. DISKPART> delete volume DiskPart successfully deleted the volume. For additional options, run the command help create vdisk at the DiskPart command prompt . After you create a VHD, you must attach it, create a partition, assign it a drive letter, and format it before it can be used . The following script (which must be run within a DiskPart session) demonstrates how to do this . create vdisk file="C:\vdisks\disk1.vhd" maximum=16000 attach vdisk create partition primary assign letter=g format Working with Volumes CHapTER 16 621 Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.
File System Fragmentation As files are created, deleted, and modified over time, their size and physical location on the hard disk will change . If a file size needs to increase and the hard disk doesn’t have room directly adjacent to the existing file, the file system automatically places the new portion of the file where it can find the room and then marks the necessary structures so that the file system can find the entire file when an application needs it . The file is now in two (or more) fragments . Fragmentation is normal behavior and is completely transparent to both applications and users . The problem is that over time, more and more files become fragmented and even highly fragmented, increasing the amount of time that it takes for the hard disk controller to locate all of the fragments . Not only does this slow down file access, but it also places additional stress on the hard disk itself . By default, Windows Vista and Windows 7 will defragment the hard drive at 1:00 A .M . every Wednesday . If the computer is off at this time, defragmentation will start shortly after the computer boots next . Ideally, defragmentation will run when the computer is not in use, minimizing the performance impact . However, the user impact is minimal because the de- fragmenter uses both low CPU priority and low-priority input/output (I/O) . Unlike earlier versions of Windows, Windows 7 recognizes solid-state drives (SSDs) and disables automatic defragmentation . Defragmentation does not improve the performance of SSDs and can decrease the lifetime of the SSD by unnecessarily reading and writing data . HoW it WoRKS Defragmentation Algorithm Improvements M any systems administrators have been captivated by the graphical defragmen- tation displays in previous versions of Windows. You’ll notice the graphics are gone in Windows Vista and Windows 7. Unfortunately, displaying the layout of files and highlighting files that had even one fragmentation made many performance- focused administrators obsessed with eliminating every single fragmented file. Fragmentation does reduce disk performance, but having a few fragments in a large file doesn’t make a difference—even years of reading and writing a large file with a single fragment would never add up to a significant amount of time. For this reason, Microsoft tweaked the defragmentation algorithm so that it does not defragment a file if a segment is longer than 64 MB. In those circumstances, the relatively signifi- cant effort required to rearrange files just to combine two 64-MB fragments isn’t worth the effort, so Windows doesn’t bother. If you run a different defragmentation tool (including the defragmenter in Windows Xp), those fragments will show up, and they’ll probably look significant because the fragmented file is so large. (Typically, the entire file appears red if it has even a single fragment.) Trust the algorithm, though—a few fragments don’t matter. 622 CHapTER 16 Managing Disks and File Systems Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark.