Stephen, on-line backup isn't really backup at all. Sure, it's convenient a the time, but the only risk it protects you against is physical failure of a hard drive. In other words, a mirrored system is protecting you against maybe 5% or at most 10% of the risk.
Don't do it!
What you need is off-line backup - a backup system that protects you against all the possible failures that lead to data loss, not just one relatively rare type of failure.
There are many ways to achieve this. I'll list a few of them, though there are several others.
* External drives (USB, Firewire, or etc.)
* DVD-R (tedious but very effective
* Second, networked system (very convenient, not as safe as the two just mentioned though)
* Drive caddies (cheapest method of all, not too difficult to administer)
* Commercial broadband backup (probably not suitable for your volume of data)
* Tape drives. Can be worth considering, but you need to go for a higher-end unit, so hard drives often work out cheaper.
* And so on
All of the methods I just mentioned, when properly used (which isn't difficult or too tedious) protect you against all risks, not just the low-probability risk of drive failure.
|