What does RAID do for me?

A very powerful infrastructure configuration (though commonly misunderstood) is RAID, short for Redundant Array of Independent Disks. As the name implies, the purpose of a RAID configuration is to provide redundancy for your hard drive, and depending on the configuration can be an excellent way to improve redundancy or performance for your drives. We will be reviewing some of the more common configurations, as well as what they can and cannot do.

When most people that are somewhat familiar with RAID think of the concept, they are thinking of two hard drives that act as a mirror to one another. This is known as RAID 1, and it does exactly that - the two hard drives are mirrors of each other, so if one drive fails, your data isn’t lost. However, RAID 1 can’t keep a software corruption out of the picture (it is an exact mirror, for better and for worse) so if you have completely corrupted your system, RAID 1 unfortunately will do nothing for you. In addition, the cost to implement RAID 1 is relatively high, since you need to buy two hard drives to get the storage of one. Theoretically this can continue up to four drives equaling two and so forth, but most of the time different RAIDs are used in these cases.

RAID 5 is a more efficient method than RAID 1 because it uses data striping at the block level; with parity among drives so that you can recover from failures of any of the hard drives that you may have. However, the parity comes with a cost, as it slows down read speeds when pulling data back out of your configuration. RAID 5 also requires more hard drives than RAID 1, with a minimum of four hard drives in place before we can implement it in our Dedicated Server solutions.

RAID 10 is a striped RAID 0 array that is mirrored like RAID 1. RAID 0 on its own is purely for performance and doesn’t have any redundancy, which is why we didn’t mention it before - as a standalone configuration there isn’t much use for it in the business world (it is very popular in the gaming world for players however). By combining the best of these two configurations, RAID 10 is a very high performance configuration that is fault tolerant - in some cases RAID 10 can recover from multiple drives failing. However, it also has the same flaws as RAID 1 - you need to purchase multiple hard drives to get the same storage as a single drive.