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BACKUP AND RESTORATION
Backup strategies are based on the effective requirements to restore data. Restoration can range from periodic retrieval of archived information to a full-scale recovery from disaster.
Backup Strategy Basics
A backup strategy requires an understanding of the types of backup available along with their methods and applicable rules. Windows Server 2003 backup should be planned according to these considerations, among others:
Frequency of backup.
This varies according to nature of the data. Mission-critical data should be backed up at least daily. Less critical data can be scheduled for backup over the weekend.
Archival media.
Depending on the amount of information to be backed up, data can be archived on a variety of media. Capacity of the media must be determined beforehand.
Files/folders selection.
The administrator needs a plan for the backup of critical system files (like the Active Directory or the Registry), mission-critical files, and ordinary data files. The files and folders to be backed up must be selected first.
Network and local backup.
The plan must include where the backup is to be archived. Obviously, remote backups assume the availability of a fast and reliable network connection. Security over the remote connection is also a consideration.
Secure storage of backup media.
The archival plan must include securing media from theft, damage, and unauthorized review.
Available Backup Types
There are four basic Windows Server 2003 backup schemes. Each has its strengths. In most IT environments, all four types are employed at different times, and they can be combined as well. In some backup schemes, when a file changes, a marker is set to flag the change. This marker is known as an archive attribute. A backup will clear the marker.
Daily.
Selected file and folder backup is performed daily but only of files that were changed during that day. Markers are not reset in daily backups.
Incremental.
Only files and folders that have set markers are sent for backup. The marker is then cleared so that future incremental backups do not include them. Incremental backups can be scheduled at any time.
Copy.
All selected files and folders are archived without clearing markers.
Normal.
All selected files and folders are backed up and their existing markers cleared. Normal backup does not rely on markers but backs up all selected files or folders.
Who Can Back Up
The Administrators, Backup Operators, and Server Operators groups have authority to back up and restore all files of a local computer. Domain Administrator and Domain Backup Operators can perform domainwide backups.
Individual users can back up their own files and folders as well as those in which they have Read, Read & Execute, Modify, or Full Control permissions. File and folder restoration by a user requires Write, Modify, or Full Control permissions.
CAUTION
Allowing a normal user with mere Read permission to back up any file or folder creates security risks. For example, such a file could be backed up and spirited out of the organization. It is therefore advised that these rights be restricted. Restrict backup to the owner of the file and the Administrator or Backup Operator. This restriction should be set in the Backup Job Information dialog box.
Managing Backups with Ntbackup
The backup tool, Ntbackup, is invoked from either the Start Accessories System Tools Backup menu or the command-line Ntbackup utility available through command prompt or Start Run Ntbackup. The Backup and Restore Wizard is shown in Figure 14.13 after selection of Advanced Mode from the opening wizard screen.
Figure 14.13. The Backup and Restore Wizard (Advanced Mode)
We recommend the Advanced Mode because it affords greater control. However, if you select to use the base approach, the Backup Wizard walks you through the standard backup decisions, the first of which is presented in the initial dialog box. The first option is to back up everything on the system; the second is to select specific files and folders; and the third is to back up system state data. Selecting any of these options opens up other options.
Let''s select the option to back up selected files, drives, or network data, which invokes a dialog box that permits selection of the items to be backed up, as shown in Figure 14.14.
Figure 14.14. The Backup Selection Dialog (Advanced)
The next task is to determine where the data will be saved. Use the Browse button to navigate to the chosen local or network location and then select OK to finish the backup. The Advanced button fine-tunes this process. As Figure 14.15 shows, you can select the type of backup, indicate its destination, and enter its name. Subsequent dialog boxes allow you to append information such as the name of the archived volume and the date and time it is to be backed up.
Figure 14.15. Selecting the Type of Backup (Basic Backup)
The time for the backup is selected through the Schedule tab in the Advance Mode (Figure 14.16). Double-click the date. The Backup Wizard is then launched to define the scope and type of backup, as just reviewed.
Figure 14.16. Backup Scheduling
Changing Default Backup Options
The Ntbackup tool provides a number of options that fit the organization''s backup needs. From the Ntbackup application, select Tools and then Options. Make the appropriate changes in any of the following tabs:
General
General backup rules and reporting methods
Restore
Restore rules
Backup Type
Default backup types, as discussed previously
Backup Log
Default settings
Excluded Files
Exclusionary rules for backup and restore
Restoration Basics
Restoration is used primarily to recover lost or damaged data. For this reason, maintaining accurate records on backups can save valuable time. With proper records, it is possible to apply only the incremental or daily backup that contains the lost or damaged data. If more radical restoration is required, begin with the last normal backup and then apply incremental backup sequentially until full restoration is achieved.
How to Restore
The process of restoration is carried out by the Restore Wizard, which is available from the Ntbackup application or the Start Accessories System Tools Backup menu (Figure 14.17). Again, we recommend use of the Advance Mode from the initial wizard screen for greater control. This wizard requires you to identify the media and files or folders to be restored according to the following basic procedure:
Open the Ntbackup application, select Advance Mode from the initial wizard screen, select Restore and Manage Media tab, double-click the folders or files to be restored (Figure 14.18). Select Start Restore.
Figure 14.18. Selecting Files/Folders for Restoration
Select the file, folder, or drive to be restored (expand if necessary as you would open subtrees in Explorer). Click Start Restore
The next prompt allows you to restore the file to the original location, an alternative location, or a single folder (Figure 14.19). Select the location and click Start Restore.
Figure 14.19. Selecting the Restoration Location (see lower half of screen)
The next set of options allows you to choose how the restored files will be written. The choices are shown in Figure 14.20. Select the option desired and click Start Restore.
Figure 14.20. Writing Restored Files
Figure 14.17. Backup and Restoration Options
NOTEIt is generally advisable to restore files and folders initially in a temporary directory that can be used for testing, which will indicate if the backup data is corrupt or the media are damaged. This kind of testing safeguards against writing corrupted backup data over current data.
Using Batch Restoration
The Ntbackup utility can be employed in a command-line mode to create batch backups, as the following examples illustrate.
Creating a Normal Batch Backup
A normal batch backup is created by typing a command-line statement that is similar to the one that follows from the Start Run menu or from the command prompt:
ntbackup backup \\ECC-1\c$ /m normal /j " My Current Job 1" /p "Backup"
/n "Command Backup 1" /d " My Command Line
Backup Test " /v:yes /r:yes /l:s /rs:yes /hc:on
A brief description of the command line follows:
Ntbackup backup instructs the utility that it is using backup mode.
\\ECC-1\c$ identifies a remote share known as ECC-1.
/m normal sets the backup type to normal.
/j "My Current Job 1" is the name of the backup.
/p "Backup" requests that a media pool be used.
/n "Command Backup 1" identifies the name of the tape or disk in the media pool.
/d "My Command Line Backup Test" describes the backup.
/v:yes provides verification when the backup is completed.
/r:yes restricts access to the owner and/or administrator.
/l:s indicates that the log will show a summary statement only.
/rs:yes indicates that remote storage data will also be backed up (not recommended because of the time required).
/hc:on indicates that hardware compression is enabled.
Performing a Batch Copy Backup
A batch copy backup involves a simple command-line statement from the Start Run menu or the command prompt:
ntbackup backup c:\ /j "Copy Job 1" /a /t "Command Line Example 1" /m copy
A brief description of the command line follows:
ntbackup backup instructs the utility that it is using backup mode.
\\ECC-\c$ identifies a remote share known as ECC-1.
c:\ /j "Copy Job 1" identifies the name of the backup for drive c:.
/t /a "Command Line Example" appends the backup to a tape named a "Command Line Example."
/m copy sets the type of backup to the copy type.
Authoritative Restoration
Authoritative restoration is useful when system state data such as that associated with Active Directory, domain controllers, or the Registry must be restored. As a default, Windows Server 2003 backup is done in a nonauthoritative mode. Since objects are stored with sequential identification numbers, a nonauthoritative restore will not overwrite an object with a more recent number. Instead, it regards the archived data simply as old. If the Active Directory or Registry has been damaged or corrupted in some fashion, the system state data cannot be restored unless an authoritative override is applied.
The ntdsutil shipped with the Windows Server 2003 permits you to mark objects that need to be authoritatively restored. Update sequence names are changed to a higher level, which allows the substitution of the object. Where multiple domain controllers exist, this new number will be treated as an update and replicated throughout the domain. The ntdsutil must be run after the system state data has been restored and before the system is restarted.
