Imagine the following scenario: You come in to work in the morning and switch on your PC as usual. As you reach for your first cup of coffee, you make the horrific discovery that the files you were working on just last night can no longer be opened. Desperately searching for the error, the realization dawns on you that a good deal of other critical data is also missing.

Such data loss can be caused by a variety of problems ranging from trivial hardware defects to malware such as Trojan horses and viruses to unforeseeable accidents such as flooding, fires or even earthquakes. In short, your data is always potentially at risk. However, there are ways of preventing data loss. Having the right strategy is key, and it should always be centred on backing up your files.

With S-ATA superseding Ultra-ATA (P-ATA) and motherboards sporting ever more integrated functionality at ever lower prices, hardware RAID solutions are slowly gaining a foothold in the SOHO and home user segment. Simply put, a RAID 1 system consists of at least two hard drives, both of which always contain the same data. That is why RAID 1 mode is also called disk mirroring. Thus, your data is safe even if one of the drives fails – since you have an exact copy on the other drive.

Your opinion counts. Take part in our survey for a chance to win over £3,000 in prizes!

By using a RAID array of this type, you at least achieve data redundancy. However, even a RAID array is not an absolute insurance against data loss. For example, inconsistent data sets may be caused by occurrences such as a power outage, when the drives are unable to finish writing the data. Also, if malware like viruses make changes to the data, these changes are automatically copied to the mirror disk and cannot be undone or prevented simply by using a RAID setup. It should be understood that using a RAID based solution only means ensuring data preservation by safeguarding against disk failure and does not constitute a backup in any way.

Backup Options

Not all too long ago, a simple floppy disk was all you needed to create a backup of your most important files. However, due to continually increasing file sizes and ever greater data sets, the floppy lost favor with home users and was replaced by other mediums. In its place, users often turned to Iomega’s Zip drives that initially offered a capacity of 100 MB. For a short while, a competing magneto-optical format called LS or SuperDisk appeared on the market, its mediums offering between 120 MB or 240 MB of storage space. Additionally, the LS/SuperDisk drives were downward compatible with the conventional 3.5” floppy disk with its 1.44 MB capacity. However, due to a high failure rate and high prices, the LS/SuperDisk drives lost out to the Zip drive.

Mediums for the Zip drive were available with 100 MB, 250 MB and 750 MB. While this was very initially quite a lot of storage space, especially coming from the floppy, CD-RWs and USB thumb drives soon began to usurp the Zip drive’s position as the backup medium of choice. Still, the amount of data found on the average computer continued to increase. The advent of rewritable DVDs with their capacity of up to 4.7 GB and their comparatively low price then marked the end of the proprietary solutions in the SOHO and private segment and the dominance of the cheap disc-based solutions.

Larger companies have much higher data volumes that need backing up, and so this segment has traditionally favoured magnetic tape storage solutions. The capacity of the media depends on the technology the device uses. Aside from DDS (Digital Data Storage) drives and media with a capacity of 36 GB, there are also other techniques such as SLR (Scalable Linear Recording) with up to 70 GB, DLT (Digital Linear Tape) with up to 160 GB and finally LTO (Linear Tape Open) with up to 800 GB. This capacity can usually also be increased or used more efficiently by employing data compression techniques during the backup process. If the data volume exceeds even the limits that can be reached using compression, so called auto loaders can come to the administrator’s help. These autoloaders automatically change media according to the backup strategy specified by the backup software. However, due to their higher price and operating cost, tape-based solutions are usually not very attractive to users in the private and SOHO segment. Thus, solutions need to be found for these users.