There is no argument that every computer user must have some kind of backup system in place to safeguard their data. There are generally two options available for home users to make backups: online backup services and local backups (e.g. on an external hard drive attached to your computer). While personally I am not a fan of online backup services due to privacy considerations with online backup services, I will not discuss the advantages and disadvantages of these two methods in this article; rather I will discuss the manner in which the backup is stored and how the files are accessible to the user. In Part I of this article I will review the concept of backup images, also known as restore points, while in Part II I will discuss file and folder-level backups.
1. Image Backups. An image backup is a backup strategy whereby a snapshot or copy is made of the data on a hard drive; usually an image is created of an entire hard drive. If the user then winds up with a major system problem (e.g corrupted files from a virus or malware, the deletion of a major chunk of data), then a system image is helpful because it can restore you to your “last good point”. You may also hear this type of backup being called “a restore point”. You can easily create multiple restore points so you can “move around in time” in terms of your backup. If you create a restore image on Monday, and you system gets corrupted on Tuesday, you can easily go back to Monday’s “state” by restoring the image.
There are, however, two disadvantages of this methodology, one of which may not apply to your specific imaging system or software. The first disadvantage is that many of the backup image software that is used by home users (e.g. the software the commonly comes with an external hard drive) does not allow file-level restoration. Let’s look at file-level restoration with an example: let’s say you created a restore point on Monday. On Tuesday you are working on an important file and for some reason you accidentally overwrite and ruin this file, and now you need to go back to the original copy. With some of these image backup packages, you cannot go back and restore a single file – e.g. the file that you “ruined” on Tuesday – you must go and restore the ENTIRE system back to the way it was on Monday. If you made no other changes to your computer or created any other files then this isn’t an issue, but if you did make change (which you likely did in 24hours) all of the files that are “different” will be lost when you restore back in time to Monday’s restore point.
The second limitation is that with many of these backup image packages, you cannot restore the image on a new hard drive if your original drive fails. For example, let’s say you have a laptop with a hard drive and you create a restore point or similar drive image. The next day your hard drive fails, and the company sends you a new hard drive. When you go to restore the image you created, the restore of the image fails and the image is unusable. The problem, therefore, is that some images will only work on the original hard drive for which the image was created. Further, even if you are able to get the image to restore, there are sometime issues with Windows activation.
Thus, backup images are useful for restore points after major system problems such as virus, malware, and configuration issues. However, restore points are not always helpful for file (or folder)-level restores, or for complete system restores when the original hard drive has failed due to mechanical reasons. When using a backup image it is therefore absolutely critical to find out ahead of time if (1) your backup image software allows file and folder-level access (see Part II of this article) and (2) if you can use the image on a hard drive other than the original drive you used to create the image.
In Part II (coming soon) I will go over file and folder-level backups.