# Windows NT Server 4.0 Administration Notes
Module 11: Backing up and Restoring Data
Introduction to the Windows NT Backup Program
To back up and restore data: The tape drive must be supported on the HCL. User must have appropriate rights All users can back up files/folder for which they have the Read permission. To back up all files and folders, a user must have the Backup Files and Directories user right. To restore all files and folders, a user must have the Restore Files and Directories user right. Members of the Backup Operators or Server Operators groups have these right. NT Backup only supports backing up to tape Guidelines for backing up data: Always back up: Critical files and folders Registry on any Domain Controller (in here there is a copy of directory database) Backup can only backup the Registry or event logs on computers where the files are located. Periodically back up files that seldom change or not critical info. Do not back up temporary files, as they change constantly and are rarely used to recover data. Determining the Backup Type to Use: There are 5 backup types or methods. Use a combination of these types in your strategy.
Type | Backs Up | Marker
Normal | All selected files and folders. | Yes
Copy | All selected files and folders. | No
Incremental | Selected files and folders if changed since the last back up. | Yes
Differential | Selected files and folders if changed since the last back up. | No
Daily Copy | Files and folders that changed during that day | No
Windows NT can set a back up marker, also known as the archive attribute. This indicates that the file has been backed up.
Backup Sets, Catalogs and Backup Logs
Backup set is used to describe a group of files or folders on a single volume from a single back up operation. Family set. This term is used when a single back up operation requires multiple tapes. A Catalog is a graphical representation of the back up. Windows NT automatically creates catalogs during a backup and stores them on a tape. Two types: Tape catalog shows all the back up sets on a tape. Backup set catalog shows all files and folders in the backup set. Before you restore files, you must load the catalogs. Than you can select the backup sets, files and folders that you want to restore. Backup log is a text file that records backup operations.
Setting Tape and Backup Options
include pages 224-225 If you select Backup in Administrative Tools, in the Backup dialog box, click Backup and set the following options: In Tape Name box, type a name that identifies the server being backed up (up to 32 characters). If you also select the Append option, the Tape Name box is not available. Operation Append--> adds a new backup set Replace--> overwrites the old backup set Verify After Backup--> confirms files are backed up accurately. Backup Registry--> adds a copy of the registry to the backed up set. Only available if you select at least one other file on the volume containing the Registry file. Restrict Access to Owner or Administrator --> limits access to the tape to Administrators, Backup Operators or user who performed backup. If you back up the Registry you should select it. Hardware Compression --> select this option if you use this tape with tape drives that support data compression. Only available if tape drive supports it. Backup Set Information box Description Backup Type box; same options as in table. Log Information box Log File box (default D:\WINNT\BACKUP.LOG) Full Detail --> logs all backup information (names, skipped, corrupted) Summary Only --> logs only major backup operations (loading tape, starting backup, failing to open a file) Don't Log --> no info is logged
Scheduling a Backup Using a Batch File
You can schedule a batch file backup using the At command (At.exe) to run at a specific time. Syntax: ntbackup backup [pathname [options]] Ntbackup.exe options:
Option | Description
/a | Appends backup set after any existing backup set
/b | Backs up local Registry, but only if you back up another file from the same volume.
/d "text" | Describes backup set. Description appears when you view the tape dialog.
/e | Logs exceptions, such as summary log
/l filename | Assigns a file name to the log file; default D:\WINNT\BACKUP.LOG
/r | Limits access to the tape to Administrators, Backup Operators or user who performed backup.
/t {Normal |Copy | Incremental | Differential | Daily} | Specifies backup type. Default type is Normal.
/v | Confirms that files were backed up accurately.
/hc: {on | off} | Enables or disables hardware compression for tape drives that support it. Default is hardware compression off.
cmd /c net use x:\\servername\sharename | Connects to a remote share
cmd /c net use x: /delete | Disconnects from a remote share
Using the At Command
The Schedule Service must be running on the computer that will run the scheduled task. The following table describes the At.exe options
Option | Description
\\computer_name | Specifies a remote computer.
id | Assigns an identification number to a scheduled command
/delete | Cancels a scheduled command
time | Specifies the time the command is to run (24 hour time notation: 00:00-23:59)
/interactive | Allows the job to interact with the desktop of the user who is logged on at the time the job runs.
/every:date[,…] | Specifies the weekdays or days of the month a command is to run.
/next:date[,…] | Specifies the next weekdays or days of the month a command is to run.
"command" | Specifies the program or batch file to run.
Tips for backing up: A good backup strategy. Keep documentation for each backup. Perform a trial restore periodically to verify that your files were properly backed up. Keep a record of multiple backups in a calendar format showing the days you do backups.
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Comments and suggestions? E-mail me at grantwil@sk.sympatico.ca
Last Updated: Wednesday, March 10, 1999 | Grant Wilson, Tisdale, SK. Canada