[ The PC Guide | Systems and Components Reference Guide | Hard Disk Drives | Hard Disk Logical Structures and File Systems | Disk Partitioning and Formatting Programs ]

Drive Imaging Utilities (Drive Image, Norton Ghost, etc.)

System builders and administrators--people who create and deploy many PCs, typically in a business or corporate setting--often have a need for special tools to do particular tasks related to hard disk setup. Imagine that you have purchased 100 new PCs for your office, and licensed 100 copies of each of the appropriate pieces of software to be installed on them. Normally, you would have to install the operating system and each application individually onto each machine. This is boring, repetitive work that would take hundreds of hours to do manually.

A better approach is to do the following instead. Install the operating system and applications on one PC, and thoroughly test the installation. When that system is verified to be working, create an image of the partition on that PC. Copy the partition to each of the other 99 systems, and then create a new partition from the image on each local PC. This would still take many hours to do, but would take only a fraction of the time required for 100 separate manual system setups.

The power of this sort of automation is such that several different drive imaging utilities have been created over the years to enable administrators to do exactly what I described. The program lets you "capture" a partition and save it as a simple file. The file can be moved to other PCs, using a removable storage device, network, or even the Internet. On the other PC it can be restored into a proper partition. Two of the most common imaging utilities are Drive Image by PowerQuest, and Ghost, which was purchased from a smaller developer by Symantec several years ago and included in the Norton line of disk utilities.

As I mentioned in the page on disk copying utilities, programs such as Drive Copy are basically "stripped down" versions of full-featured third-party partitioning programs like Partition Magic. In a similar way, drive imaging programs are "subsets" of full partitioning programs, but include the ability to save the partition as an image file, which Partition Magic doesn't allow. These utilities also usually include built-in compression, which allows the target image file to be made smaller than the partition it contains, to save disk space and transfer time when the file is copied.

While imaging programs were developed primarily for large-scale systems deployment, they have also found a niche as a backup product. While most conventional backup software concentrates on copying the files on a hard disk one by one, disk imaging utilities can be used to backup an entire hard disk partition, as a whole. I use Drive Image as part of my own backup strategy. In addition to regularly backing up files that have changed, I periodically take an image of my entire hard disk and store it on an external drive. The advantage of this is that if I ever have a hard disk crash, I can replace the disk and rebuild the partition from the stored image file. Everything will be exactly as it was when I made the image. (In fact, I had an opportunity to test this when I had a disk go south on my notebook in 2000.)

Note: You can use a drive imaging program to copy a partition from one disk to another. Just create an image file on one disk and then restore it to the second. However, if you only require this copying ability, you may be better off just using a disk copying utility. You may save some money as well, since disk copying utilities are generally cheaper than imaging programs.

Next: Disk Compression

Home  -  Search  -  Topics  -  Up