STACER NOTE                                               STACKER NOTE

Subject:  Backing Up Stacker Drives  (Applies to Stacker 1.x, 2.x, and 3.0
STAC FAX Index #2404   2/20/92 




Background.
You can use your favorite backup program, like Fastback, 
Norton Backup, or the DOS backup program to back up your Stacker drives.  
A Stacker drive may be backed up like any other drive.  If you Stacked drive 
C:, have your backup program back up the files on Stacker drive C:. 


Will the backed up files be in compressed or uncompressed form?
Stacker "Un-Stacks" files as they are read from the hard drive then 
hands them to the backup software in their original, uncompressed state.  
If the backup software uses compression, it will recompress the files 
before storing them to diskette or tape.  This means that the files can 
be restored to any drive, Stacked or not.


What about the STACVOL file and the files on the uncompressed host drive?
The STACVOL.xxx file contains all the files and free space for the Stacker 
drive.  Therefore, you do not need to back up this file if the Stacker 
drive has been backed up.  In addition to backing up your Stacker drives, 
you will want to back-up the boot drive.  If you have Stacked drive C: it 
will be the drive that host's the C: Stacker drive. For example, to 
determine the boot drive, use the "STACKER" command. Type:

	C:\STACKER\STACKER  <ENTER>

The output will look similar to:
	
	Stacker Disk Mount Utility - 2.01, (c) 1990-92 Stac Electronics, 
	Carlsbad, CA  
	Stacker drive map:
	Drive C: was drive D: at boot time  [ D:\STACVOL.DSK = XX.XMB  ]
	Drive D: was drive C: at boot time  

The boot drive is the drive that "was drive C: at boot time".  In this 
example, Drive D: is the boot drive and host drive for Stacker drive C:.  
To backup in this situation, instruct your software to backup drive C: 
and D: but tell it not to backup D:\STACVOL.DSK.  That's because 
D:\STACVOL.DSK is the C: drive !


How do I restore my system in the event of a hard disk crash?
Depending on the severity of the crash, you may need to repartition 
and reformat the drive.  Next, you would need to install DOS.  
Then, restore the boot drive files from backup.  The next step 
is to install Stacker to create the compressed drive(s).  But before 
you do this, edit C:\Config.sys to remove the Stacker device 
driver commands. (They will be added when you reinstall Stacker.)  
The final step is to restore the files from backup to the Stacker drive(s).


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Copyright 1992, Stac Electronics