FPGA-FAQ    0021

Backing up NT4 systems

Vendor Any
FAQ Entry Author Philip Freidin
FAQ Entry Editor Philip Freidin
FAQ Entry Date 2001/06/07

Q. How can I backup a Windows NT4 system, and get all the registry stuff saved too


The solution that I use for highest quality backup is to use a program called Drive Image, from Power Quest. You exit NT, and boot from the Drive Image floppies and then make image files of disk partitions.


-- It can make and restore FAT and NTFS partitions.
-- The image files it creates can be compressed (I always do) by 50%
-- The image file can only be written to a FAT partition (big limitation), 
   so you need at least one partition that is 2GB, FAT, and in the first
   8GB of a drive, so that DrDos/MSDOS can write the image file.
   You need to keep this partition empty, so that you can pack and
   unpack image files in it.
-- The image file can be split into pieces of a specific size, i.e 600MB for saving to CD later
-- After image is created, restart NT, and write image files to CD
-- Can restore an image to a partition from a image file on CD, if CD driver and
   MSCDEX is loaded in the DOS environment
-- Reasonably fast
-- The OS it boots to on the floppies is DrDos, a DOS 6.22 look alike without
   license fees to MS. It can also run fine under real MSDOS 6.22

Since it can only write to a FAT partition, which is a limitation of the underlying OS (DrDOS or MSDOS), you run into the following problem: FAT file systems can't be over 2GB. A NTFS partition with 20GB size, and 6 GB used can't be imaged, because you can't have a FAT partition big enough to hold the compressed image.

My solution is my NT OS install partition (which is also where the registry is scattered about) is 2GB, and I install all programs to another partition, so that I don't run out of space. There will still be a  "Program Files" directory on the NT system partition, as some programs insist on being on the same drive as the NT OS, but with care, you won't run out of space. Another thing that helps is to put the NT4 Swap file on another partition, as there is no real need to back it up when imaging the NT OS partition.

So: 2GB partition for  NT OS, can be FAT or NTFS
   2GB partition, in first 8GB of disk, for saving and restoring images
   Use drive image just for saving the NT OS partition, use normal tape backup
   for everything else.

Some possible work arounds I haven't tried:

   There are loadable device drivers for MSDOS that are supposed to be able to read/write NTFS partitions. I have not tried this. I dont know how they get around the 2GB file system limit that is in MSDOS. see:


  At one time there were some addons to MSDOS that supported windows networking. If this could be added to the boot floppy for Drive Image, then maybe the image could be written to a network drive on another machine and avoid the need for 2GB FAT partition on the machine being backed up.

Wouldn't it have been great if the guys at MS had rubbed a few neurons together and not created an OS that was basically incapable of creating a reliable backup image of the OS. It's not like there wasn't 30 years worth of experience to draw upon from all the OS's that other companies have written, none of which have basic flaws like this!

Here's another link

     Every OS Sucks

Philip Freidin