Which is best - disk backup or cloning?

Helpline Q&A Directory

I have slavishly maintained a backup using my Zip drive, thinking that should a disaster occur I would be protected. The dreaded problem finally arose, requiring a hard disk reformat. Restoring was straightforward, but the results were disappointing as most of my programs had files missing and had to be reinstalled.

A more knowledgeable computer user advised me that backing up would not successfully restore full operation, and that if I wanted a complete replica of my hard drive I would need to use cloning software such as Norton Ghost. I have also been advised that my Zip drive is unsuitable, as cloning will not allow the use of more than one disk. It has been suggested that I need a second hard drive or a CD-RW drive, though this method seems restricted in capacity, too. Could you explain the advantages and disadvantages of backing up versus cloning?

Cloning, in effect, records or restores an image of your hard disk. To save space, only the blocks containing data are stored. Nevertheless, the storage medium used must be larger than the amount of space used on the disk. An advantage of cloning is that, because it works at a low level, restoring is simple and does not require Windows to be installed first. A disadvantage is that you cannot restore an individual lost file from a disk image.

Cloning software was originally intended for use by PC manufacturers or business IT departments that need to quickly roll out systems with an identical setup. However, many personal users are fans of this backup method. The usual cloning procedure is to install Windows and your essential applications and check that everything is set up as you want. Once you're happy with the setup, use Norton Ghost or an equivalent to burn an image of the system on to a CD. This can then be restored whenever Windows starts becoming flaky and you want to return your hard drive to a state you know functions well.

Backups, by contrast, work on a file-by-file basis. This means that you don't have to back up the whole system if you don't want to. It also makes it possible to retrieve individual files if you need to. You can perform incremental backups (of just the files that have changed since the last backup), making the backup process quicker.

A full system backup will back up everything on your system, so it should be just as effective as an image created by cloning software when performing a restore. You will still need a storage medium capable of holding all your data. However, backup programs are capable of spanning more than one disk or tape although it has to be said that the Microsoft Backup supplied with Windows has limitations in this area.

We don't know precisely why your restore wasn't successful but we guess that you weren't backing up your full system, resulting in some essential files failing to get backed up. Whether to stick with backups (but do a full system backup) or go for cloning is a matter of preference, as is the choice of backup medium. There's no 'best solution', but our preference is for conventional backup software as it is more flexible.

Most decent backup programs will be capable of performing a full backup on to multiple Zip disk cartridges, multiple writable CDs or, if you invest in a tape drive, tapes.