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The backup file that contains a copy of your C: drive won't be as large as your C: drive. Image Copy 2 only copies the areas of the drive that hold something.
  technofile
Al Fasoldt's reviews and commentaries, continuously available online since 1983

How to make backups, Part 2


May 16, 1999

By Al Fasoldt
Copyright ©1999, The Syracuse Newspapers

   Last week I told you how to make simple backup copies of things you've created, such as word processor documents. This week I'll explain how easy it is to make full backups of your entire computer system.
   The method I'm going to tell you about is not for everyone. If your PC has only one hard drive and you can't afford to add a second one, the method I recommend might not work for you. I'll explain this, so stick with me.
   Because of the way Windows works, some methods of doing full backups don't work reliably. That's why you won't hear me recommending some of the techniques others use. The most effective backup method is the brute-force approach: You save everything. And I mean every, as in the entire drive. Not all the files. The entire drive.
   A program that does this is usually called a disk-image utility. The best is Drive Image from PowerQuest. It costs about $60 at discount computer stores. You can buy it directly from PowerQuest for $70.
   Drive Image makes an exact copy of a drive and stores that copy as a file on another drive. That's why you need two drives. Drive Image 2 can use a lot of compression to make the copy as small as possible, or you can tell it to use moerate compression to speed up copying. You can also turn off compression.
   Even if you turn off compression, the backup (image) file that contains a copy of your C: drive won't be as large as your C: drive. Image Image only copies the areas of the drive that hold something. Empty hard drive sectors are not copied. The best way to use Drive Image is to turn on maximum compression (the setting is very easy to find) and skip all other extra options.
   The basic idea is that Drive Image copies your drive and turns it into a file. It saves that file on another drive. (It can't save it on the drive it's copying.) To restore that drive later, you run Drive Image again -- booting from a floppy disk and running it from the floppy if you have to -- and click on the restore buttons.
   I said earlier that you need a second drive. In most PCs, you can add a second drive right inside the case. You'll find an empty drive cage and some connectors waiting when you look inside. Drives have to be prepared using software that comes with Windows, so get a good book on Windows before you do this. ("Windows 95 Secrets" and Windows 98 Secrets" by Davis and Straub from IDG Books are the best.)
   The second drive doesn't have to be another hard drive. It can be a partition -- a section of a drive -- or it can be a removable drive such as a Zip drive. It can't be a recordable CD-ROM (a CD-R or CD-RW), although a CD recorder is ideal for permanent storage of drive images.
   Let's take a look at those options.
   Partitions: PCs sold more than a year ago often have a single hard drive sectioned into partitions, which function the same as physically separate drives. Our IBM Aptiva, for example, came with C:, D: and E: drives, but had only one physical drive. You can use a partition to store a drive image file if the partition has enough free space. It's not hard to do the math. If your C: drive is, say, 2 gigabytes in total size and has 800 megabytes free, it's got 1,200,000 megabytes of stuff on it. Drive Image 2 probably will squeeze that down to 600 megabytes. If you can free up at least 600 megabytes on another partition, you might be able to make an image copy of your C: drive.
   Removable drives: Drive Image 2 can break its image files into small pieces so they'll fit on small-capacity disks such as a Zip disk. (You can't break up an image into tiny pieces to fit onto a floppy disk ñ and you wouldn't want to anyway, since you'd need a few thousand floppies to back up a typical hard drive.) I don't recommend Zip disks for this kind of backup because they don't hold much -- 100 megabytes is not much capacity these days -- but the newer 250-megabyte Zip disks will work better.
   But use your head. Copying a huge drive image that's been broken into chunks so it will fit onto Zip disks can cost you a lot -- and that's for one backup copy only. (You'll always want at least two for safety.) A 2-gigabyte image would take up 20 Zip disks, at a cost of $400 or so. Spending that much for a single backup copy of a large drive is nuts.
   CD-ROM recorders: CD-R and CR-RW drives make a lot of sense because the blank disks you record on are very, very cheap. The ones I buy cost $1 each, and I've seen even cheaper prices ranging from free (the rebates covered the entire cost) to about 80 cents a disk. CD-RW drives can make CD-R recordings, so don't spend a lot of money for CD-RW disks to copy image files. You'll want your image backups to be non-rewritable. You can't afford the risk of losing them.
   Here's how I do image backups. First I clean up the drive, getting rid of temporary files and so forth. Then I make sure there's enough space on a second drive to hold the image. Then I run Drive Image, telling it to split the image into 650-megabyte chunks (so they'll fit on a CD). When it's done, I copy the separate parts of the image to CDs.