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Creating and restoring a disk image

For years I have been complaining to anyone who would listen that Microsoft Windows is a fundamentally flawed operating system (OK, it is the best, probably, as in the Carlsberg advert, but still flawed). The particular area of weakness that I am referring to is the inability to recover ones computer from a disk crash. The situation is so awful that even in multinational companies the best that the IT group can suggest is that they will re-build your computer provided it is the standard build, and you did save your files to the network drive, didn't you. The solution that sounds reasonable is having a mirror disk inside the desktop so that when one disk breaks, the other one keeps your data secure and once you replace the broken disk everything is fine. This works for a desktop, but at a high cost and does not work in a laptop where normally only one disk is available.

So for my laptop I purchased and installed a network drive and planned to use the disk imaging method advocated by Fred Langa. The network drive was the  LinkStation Network Storage Center - 160GB from Buffalo and was simple to set up and connect to my three machines via a U.S. Robotics ADSL modem. I picked Snapshot as my imaging software as it is incorporated in Bart's Preinstalled Environment (BartPE) bootable live windows CD/DVD and promises to do a full image of a machine while that machine is running Windows. Creating the image file was simplicity itself. I purchased a new laptop hard disk, installed it in my laptop, booted from BartPE and started to read the documentation.

Well, my laptop is a bit of a strange beast. It came with a restore partition as drive C: and with Windows XP on drive D:. I also installed a Linux on 3 further partitions in the last 20GB of the disk. Since I never use Linux except for fun, I was prepared to lose this. The Snapshot documentation mentioned the "restore partitionstructure" command that needs to be run from DOS. I opened the command prompt and tried to run this command; of course it failed. The command prompt is NOT the same as DOS. Next began a hunt for how to make a DOS bootup disk. Both the Snapshot site and Bart's site talked about making a bootable floppy, but the information on how to build a bootable DOS CD with network support was well hidden and Bart no longer supports it. By the time I had found out how to make one and tried it (only to have it fail to recognize my network card) I knew enough about how to add the correct network driver for my machine. Even now my problems were not over because having connected to my network drive, doing a DIR resulted in something like, "Extend error" (I forget the exact words). How many modern PC users would know that DOS used 8 character file names? And that when long file names were introduced, the file name was 6 characters followed by a "~" and a number? And this knowledge was useless as well; I had to rename my directories on the network drive to 8 characters and navigate blind to the correct place on my laptop booted in DOS. Even then the system failed to recognize "snapshot" as a command and insisted that I enter "snapshot.exe".

I restored the partition structure, restored the disk image and booted up. All I got was a string of "L 99 99 99...". A quick search on the Internet confirmed my suspicion that it was my Linux boot loader that was causing the problem. To get rid of this, you need the Fdisk /mbr command, so more searching was necessary to get an accessible copy of Fdisk. At last, the new hard disk booted and all my data had been restored (as far as I know).

How easy all this would have been had Windows was a complete operating system that could bootstrap its own setup from a read-only medium? Or if hard disk manufacturers had a utility that performed these sorts of disk operations competently? Instead, the average user has to struggle with third party tools and with documentation written in highly technical language that only an expert could understand. No wonder most people prefer to lose their data on their hard disk than spend all the time necessary to create and test a proper method of backup and restore!

Although I have a process that appears to work, I am still not happy. My personal data has been secured for years because I am careful to restricted it to certain directories that I backup by automatic processes. But why can't my machine be secured in the same way? Why do I have to manage sets of disk images, keep CDs handy and try to remember a horrible sequence of operations? It is about time Microsoft or someone else set about finding a solution to this problem that is accessible to the naive computer user.

 

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Richard Blazek


© 2005-6

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