Choosing the right RAID for your business
As businesses grow, so does their need for data storage solutions offering superior capacities, performance and reliability.
For many SMEs, the solution to this problem is to utilise RAID arrays. Such a setup can offer impressive read/write speeds, increased protection against data loss and capacities that are easily scaled. The benefits of a RAID differ greatly depending on the way they are setup, however, and this can make it difficult for decision makers to settle on which RAID arrangement best meets their business’s needs. As a business that has not only seen substantial growth within a relatively short period of time but also specialises in data storage and recovery, Fields Data Recovery are ideally placed to provide a comprehensive guide on this matter.
What are RAIDs?
Before we can begin the process of stating which RAID is right for your business, it’s worth explaining what they are and what they do.
RAID is an abbreviation and stands for ‘Redundant Array of Independent/Inexpensive Disks’. To put it simply, a RAID array is a type of NAS (Network Attached Storage) housing at least two – though usually several – separate pieces of storage media. The way data is written to these pieces of media is what determines the benefits – and drawbacks – of each setup.
So, without further ado, here are the five most common RAID setups and a summary of their pros and cons:
This configuration stores data across two or more drives. Known as ‘striping’, the individual bytes that form the data are split across the drives equally so, if the setup uses four hard drives, exactly a quarter of the relevant file is stored in each. Think of it like storing a physical 100-page document across four folders – 25 pages would be stored in each.
Because data is split across several drives, each needs to read/write a smaller amount of data resulting in increased speeds. This setup also offers superior storage capacities.
RAID 0 offers no protection against data loss. If one drive fails, it is not possible to access any of the data that’s been stored on the array. As a result, you’ll either need to accept that the data’s been lost or pay a RAID recovery specialist to recover it for you.
Like RAID 0, this setup utilises two or more drives. Unlike RAID 0, it stores all of the bytes that form data to each drive in their entirety (a process referred to as ‘mirroring’). Say a RAID 1 setup contained three drives, each one would be an identical copy of the other.
As data is duplicated across all of the drives in the array, several backups are effectively created at once thus protecting your organisation from the negative consequences of data loss. As drives can read ‘portions’ of a file from each of these locations it’ll also provide better read speeds.
As data is always being written to each drive in its entirety, this array offers no improvements on performance when writing data and, as data is written onto each drive in its entirety, there’s no improvement in capacity.
Also, whilst it provides businesses with a basic backup plan, a RAID 1 setup doesn’t protect against human error or physical damage.
RAID 5 setups use ‘striping’ like a RAID 0 but also use an additional drive to store ‘parity data’. In laymen’s terms this additional drive can be used to reconstruct any data lost in the event that one drive fails.
‘Striping’ offers superior read performance whilst the additional drive offers a solution in the event of one primary drive failing. This setup also offers enhanced storage capacity.
Whilst this setup’s use of ‘striping’ generates superior read speeds, the need to store parity data every time someone saves a file results in slow write speeds. The process of recovering data from a parity drive is also time-consuming.
Like RAID 5, RAID 6 uses a parity drive. Unlike RAID 5, though, it uses two. By using an additional parity drive, a RAID 6 can rebuild data following two drives having failed.
The benefits of a RAID 6 are identical to a RAID 5 with one exception: this array can be rebuilt even if two drives fail.
Just like RAID 5, write speeds are slower than you’d expect and rebuilding a failed array is a slow process.
In order to offer excellent performance and protection, RAID 10 setups use both ‘striping’ and ‘mirroring’ and is also commonly referred to as RAID 1+0.
This setup offers great performance and protection against data loss.
You’ll need at least four drives and, as any data you store will be duplicated across two, the potential capacity of the array is halved. Storing large amounts of data in a RAID 10 array can become expensive as a result.
If your budget is large enough, RAID 10 offers both enhanced performance and reliability. If you only care about performance, a RAID 0 setup will provide this, whilst RAID 1 suits companies looking for increased reliability. If a compromise between cost, storage, speed and reliability is required, RAID 5 or 6 are the way to go.
Please remember, however, that a RAID array alone does not provide a comprehensive backup and data loss plan. These setups should be used alongside more robust backup such as tape or cloud storage.