The Tao Of Backup: Veracity Hard Sell

We warned you not to click, but seeing as you insisted, you obviously deserve to be subjected to...

The Veracity hard sell!

If you're a programmer, graphic designer, writer or any other kind of person who creates and manipulates information for a living, then chances are that your life's work is sitting on a hard disk somewhere. Similarly, if you're running a small business (or part of a large business), your "corporate memory" will be sitting on a few hard disks on various computers.

In both of these cases, the loss of a significant amount of data would be a total disaster that would have a major impact on your life or the business. So let's take a look at where your data actually is...

Right now, your life's work is wizzing around on a disk that's spinning around hundreds of times per second. Literally flying over the disk are the disk read and write heads which read and write data hundreds of times per second in response to your computer, whose operating system was constructed at night by a bunch of teenagers living off Jolt cola.

Are you feeling nervous now?

The average life of a hard disk is about four years (give or take a few years). After that, you will encounter an increasing number of disk errors. You could also, at any time, suffer a catastrophic failure such as a head crash or a spindle meltdown. One thing is certain: your disk will fail sometime in the next few years.

The only thing that will save your life's work when (not if) your disk crashes is your backups. Given this obvious truth, it's amazing how many people have no backups or poor backups. While ad-hoc backups will usually save you, there's a chance that you'll be unlucky and lose the lot. If you think about it (your life's work!) you'll see that it's just not worth the risk.

To be sure that your life's work is safe, you must implement a backup system that addresses all seven heads of backup: coverage, frequency, separation, history, testing, security and integrity. Remove any one of these heads, and your data will be at risk (think about it).

Of particular importance is testing. When it comes down to it, your backup system is just a big, complicated, distributed, storage system whose sole purpose is to provide the capability to restore the data fed into it. From this perspective, it seems extraordinary that so many people and organizations do not ever test their backups. But even those who test their backups by loading a backup and taking a quick look at the restored files cannot be completely sure that their backups are working.

Veracity enables you to test your backup system absolutely by certifying that the restored data is identical to the data that was backed up.To do this, take a snapshot of your disk before you perform a backup. The snapshot file is relatively small. Then backup your disk onto your backup media (tape, removable disk, network, whatever). The snapshot file will be backed up along with your data. To test a backup, simply reload it and run Veracity to see if the restored data matches the data described in the snapshot file. If so much as a bit of data has changed, Veracity will let you know. It's that simple.

Thus Veracity provides the ultimate test of your backup system by proving that the data that was restored is identical to the data that was backed up. Veracity does this using cryptographic hashes, so it's a very strong proof. Furthermore, it's a proof that is completely independent of your backup software.

It's important to realize that, while your backup software can provide assurances (e.g. the tape verify option) that it is correctly backing up your data, that the backup software is just one part of the complex of systems, software, physical objects and procedures that form your backup system, and any assurances that it provides are partial. The only test that matters is whether, then crisis comes, your backup software can restore your files onto a hard disk in exactly the same configuration as they were when they were backed up.

Veracity provides the ultimate test, by testing your backup system in the only way that matters; a backup is retrieved, loaded and the restored data is proven to be identical to the data that was originally saved. There can be no stronger test than that. Protect your life's work; use Veracity.


In addition to testing backups, Veracity can also be used to monitor changes to your data on disk before it is backed up. This is another essential (but widely neglected) requirement to preserve your data. For more information, see the Veracity web.

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