RAIDs explained

RAID stands for Redundant Array of Independent Drives – this should give you a pretty good idea of how a RAID differs from your normal hard drive. Yes, you’ve guessed it: a RAID is comprised of multiple drives rather than a single one. Thanks to something called a RAID controller, though, any device connected to an array knows to treat the drives contained within it as a single entity rather than a collection of separate ones; like if you had two separate drives inside a PC for instance.

The benefits of using RAID differ depending on a user’s needs. A collection of drives can be used to increase the operating speed of the device to which it is attached, to store significantly larger amounts of data, to provide more robust and reliable storage or, potentially, all three. These benefits differ depending on how the array has been configured, though. We've recovered data from every conceivable RAID arrangement; here’s a breakdown of the three most common arrangements:


Should an individual wish to enjoy the benefits of a quicker machine, then they can configure their array to write each piece of data to a part of each individual drive contained within its array. Each drive then takes part of the file and stores the portion that was assigned to it. Think of it like delegating a project to several rather than just one person. Many hands make light work and the task is completed more quickly. As multiple drives are used, this configuration also affords its user a larger storage device.

This configuration, though, is prone to data loss for precisely the same reason that it is quick: rather than having the entirety of a file stored on one drive, a segment of each file is split across several drives. If one of these drives therefore fails, then files become unusable as, to put it simply, part of them is lost. Oh, and as this configuration uses multiple devices the chances of it failing rise by 100 percent for each additional drive.


Should a user require additional security, then a RAID can be configured so that each drive is simply an exact copy of the others also contained within the array. Known as mirroring, this provides a more reliable form of storage as should one or more of these drives fail, the data is still present and accessible provided at least one is still active. This is solely a means of ensuring your storage strategy is more robust, however, and should be used to complement rather than replace backing up data to a separate drive as the array will still be susceptible to many of the main causes of data loss such as physical damage and viruses.


In order to enjoy the benefits of greater data storage capacity, a faster machine and additional security, an array can be configured that writes data to multiple drives whilst also storing information required for rebuilding and restoring the data (stored on the arrays primary drives) to a separate drive that is also part of the array. Should one of the main drives then fail, this drive can determine what information is missing and use this to reconstruct the data that would otherwise have been lost.

There are still drawbacks with this configuration, however. A minimum of three drives are required, for example, and should one fail, then the machine will become significantly slower as it will need to complete calculations in order to reconstruct your data until the faulty drive has been replaced.

If your RAID fails, then Fields Data Recovery can help and boast a number of locations across the globe. Contact the RAID recovery experts today!