Sooner or later every user of a computer system is going to lose an
important file. These losses have many causes: a power failure corrupting
data, a hardware failure may ruin an entire disk, or you may even accidentally
delete it yourself. If any data on your system is difficult to replace
you should be performing backups.
Types of Backups
There are generally four different types of backups: Full backups,
copy-only backups, differential backups, and incremental backups.
The Windows NT Backup Utility
Full backups, as you may have guessed makes a copy of all the designated
files to some media (usually tape) and marks those files as backed up.
This archive attribute is cleared for a file whenever it is modified.
Copy-only backups copy all of the files designated but none of them
are marked as backed up.
Differential backups copy all the files that have been modified
since the last full backup but not marked as backed up.
Incremental backups copy all the files that have been modified since
the last full backup and marks those files as backed up.
Windows NT has a backup utility that may be accessed via the Start
>Programs >Administrative Tools (Common) >Backup menu or using the
command. Access to this facility to limited to members of the Administrators
and Backup Operators groups.
||To perform a backup start the utility and from the Drives window
select the files you want to back up. In order to back up files from a
remote system you must map them to a local drive letter.
Then select the device to make the backup to from the Tapes window
and press the
To specify the parameters for the backup edit the information contained
in the Backup Information dialog box.
To restore files from a backup tape in Windows NT insert the tape containing
the desired files into the tape drive. Double click on the tapes entry
in the Tapes window and load the backup’s catalog. The catalog is
a file containing information about the contents of each particular tape.
Once the catalog is loaded select the files you would like to restore and
press the Restore button.
Alternately you can perform a backup from the command line using the
ntbackup operation path [options]
Where operation is backup or eject, and path
is a list of directories, separated by spaces, to back up. A list of most
of the options follows:
Append the backup set to the end of the tape (default is to overwrite
Verify the backup after writing it.
/R Restrict access to the tape to its owner, Administrators,
and Backup Operators.
Specify a label for the backup set. Enclose the description in quotes
if it contains spaces.
/B Back up the registry in addition to specified files.
/HC:on | off
Specify whether or not to use hardware compression.
Select the type of backup: normal | copy | incremental | differential
Specify the path to the log file for this backup operation to produce
a Full Detail log.
Use tape drive number n. The drive number can be viewed with
the Properties button on the Tape Devices control panel. This key defaults
to the default tape drive if not specified.
For example, the command:
C:\> ntbackup backup C:\ D:\ /D Friday_Night
/B /HC:on /T incremental /L F:\Logs\Fri.log
Performs an incremental backup of the C: and D: drives and the local
registry to the default tape drive using hardware compression. Existing
data on the tape is overwritten. The backup is given the name “Friday_Night”
and the log is stored on F:\Logs\Fri.log.
Although the Windows NT backup facility is easy to use it does have
some annoying shortcomings:
You must specify everything to backup every time you run a backup. This
program does not enable you to save a list of files and directories to
backup for repeated use.
You can’t even specify particular files from the command line, only entire
You can only backup file systems that have been mapped to a network drive.
This also limits you to backing up file systems that can be mapped to a
network drive i.e., those residing on other windows machines or contained
with in a SAMBA directory on a Unix machine.
You can only backup to tape.