Hands on: Get to grips with Raid

Disk failure is probably the greatest fear of any PC owner. After all, while the disk itself can be replaced, the data may not be so easy to recover.

And while we all know we should back up regularly, it’s fair to say the vast majority of us fail to put adequate contingency plans in place.

Proper backup demands that data be copied onto media which can be physically transported to another site, thereby protecting against fire, flood and theft along with disk failure.

While this is the most secure means of backing up important data, it can also be useful to build extra redundancy into your PC to at least give a first line of defence against disk failure.

Raid is a technology developed for this purpose. Standing for Redundant Array of Inexpensive hard Disks, Raid uses two or more disks working together as a single logical volume to deliver various combinations of greater reliability, performance or capacity.

It has long been employed in servers and other mission-critical applications to improve storage reliability.

Raid controllers manage all the technicalities, automatically distributing your data across multiple disks and, if required, rebuilding the array after a broken disk has been replaced.

There’s a degree of processing involved in this which, on basic budget hardware Raid controllers, is generally farmed out to your main CPU. Software-based Raid solutions, such as those built into many operating systems are normally entirely dependent on the host CPU.

Alternatively, higher-end hardware Raid controllers use dedicated onboard processors to take the strain.

With Raid controllers fitted to virtually every new motherboard these days, it has become a mainstream technology which could surely benefit desktop users wanting to protect their data.

Raid does, however, come in several different flavours and it’s important to know which is best for your requirements. Suffice it to say the basic controllers of desktop motherboards may also not be as powerful or flexible as you’d like.

And while Raid uses normal hard disks, the arrays may not be easily connected to different systems should you want to upgrade or replace your motherboard, for example.

Here we’ll examine the pros and cons of Raid then look at how popular versions work in practice.