Active Directory Backup and Restore in Windows Server 2008

Overview:

NTBACKUP with Windows Server Backup

Backup Tools and Options

Recovery Tools and Options

Key to a reliable Active Directory backup strategy

It is known to all that Active Directory domain service (ADDS) is a mission-critical component in the Windows infrastructure. If Active Directory fails, the network actually crashes. Therefore, the backup and recovery plan for Active Directory is

The foundation of security, business continuity, and compliance.

Windows server®2008 brings many new features to Active Directory®, with two features that have a major impact on backup and recovery plans: The new Windows Server Backup utility, and the acquisition and use of active Dire The ability to ctory the Volume Shadow Copy service snapshot. In this article, I'll describe the changes that these enhancements bring, and how to leverage these changes to simplify active Directory backup activities.

NTBACKUP with Windows Server Backup

Group Policy settings

Windows Server Backup provides several Group Policy settings that allow you to control the way backups work on your server to some extent. With these backup strategies, people are less at risk of accessing unauthorized data through unauthorised backups. Options include:

Allow system backups only if this option is set, Windows Server Backup can only back up critical system volumes. It cannot perform a volume backup.

Do not allow locally attached storage as a backup destination if this setting is enabled, it does not allow backups to locally attached drives. You can only back up to a network share.

Do not allow network as backup target This setting does not allow backups to any network shares.

Optical media not allowed as a backup destination if this option is set, Windows Server Backup cannot be backed up to any optical media, such as a recorded DVD drive.

Do not allow one-time run backup This setting does not allow Windows Server backup to run a specific backup that is not scheduled. Backups that are scheduled only through the Windows Server backup MMC snap-in can be run.

The NTBACKUP you know and love has disappeared since Windows nt®3.5. Instead, it is Windows Server Backup. This new tool is not just an improvement on NTBACKUP; it's a brand-new backup technology that allows you to rethink the way you back up your system.

Although Windows®server Backup is the only out-of-the-box backup solution for Windows Server 2008, it is not another feature that replaces NTBACKUP. The biggest difference is that Windows Server backup is a disk to disk backup solution, and it does not support backing up to tape. You can create a backup image on a directly attached disk volume, a network share, or even an external USB hard disk and a multiple-volume DVD that can be recorded. However, you cannot back up to tape. To be clear, you can still hook up a tape drive on a Windows Server 2008 server and copy the backup image generated by Windows Server Backup to a tape drive-but you must use other party software to do this.

NTBACKUP is a file-based backup and Restore tool, while Windows Server backup is based on volumes and blocks. Windows Server Backup processes its backup source as a volume set, and each volume is set up as a single disk block. This is much more efficient than backing up files through a file system. Processing backups on a block basis also enables Windows Server backup to use Volume Shadow Copy service snapshots to perform block-level incremental backups and to create snapshots on target volumes to simplify the use of multiple backups (and to reduce the amount of space they occupy).

Even if you are performing a full backup, Windows Server Backup can provide significant space efficiency on the target disk. For example, you can perform multiple full backups on the same volume. Because Windows Server backup uses the Volume Shadow Copy service snapshot on the destination disk where the backup image is stored, the snapshot stores only the blocks that have changed. This greatly reduces the amount of space occupied by multiple full backups. This eliminates the need to restore incremental backups by performing multiple restore operations. Although snapshots store only the amount of change per backup, Volume Shadow Copy service ensures the integrity of each backup.

Note, however, that you can only benefit from the Volume Shadow Copy service snapshot on the target when you back up to your local hard disk--windows Server Backup cannot perform a Volume Shadow Copy service operation on a backup that is stored on a DVD or a network share.

Windows Server Backup stores backup images in Microsoft® virtual hard disk (VHD) format, which can have additional benefits. You can actually get a backup image and install it into a volume in a virtual machine running under Microsoft virtual Server 2005. You can simply install the VHD in the virtual machine and browse for a specific file without having to test the restore tape to see which tape has the file. (Special note: You cannot start a virtual machine from a backup image.) Because the hardware configuration of the backup does not match the configuration of the virtual machine, Windows Server Backup cannot be used as a physical to virtual migration tool. ）

There is a disadvantage to the volume and block orientation of Windows Server Backup. Because the new tool treats the backup source as a set of volumes and blocks, it does not allow you to back up only the selected files. You must back up the entire volume. Also, by default, the backup image cannot be stored on a volume that is backed up (some methods can be configured for this; see support.microsoft.com/kb/944530). I'll discuss the profound implications of system State backups later in this article.