RAID is the linking together of two hard drives, either for performance (RAID 0) or security (RAID 1). Most computer users do not need to use RAID. If you are unsure of what RAID is, have a quick read below to see if you think it will benefit you.
A dictionary definition: What is RAID? - RAID "(Redundant Array of Inexpensive Disks) is a method whereby information is spread across several disks, using techniques such as disk striping (RAID Level 0) and disk mirroring (RAID level 1) to achieve redundancy, lower latency and/or higher bandwidth for reading
and/or writing, and data recoverability."
RAID 0: Striping
RAID level 0 refers to striping data across multiple disks without any redundant information. Striping can be used to enhance performance in either a request rate intensive or transfer rate intensive environment. Unfortunately, striping reduces the level of data availability since a disk failure will cause the entire array to be inaccessible.
Advantages:
High performance
No cost penalty - all storage is usable
Disadvantages:
Significantly reduced data availability - all data is lost if one hard drive fails.
RAID 1: Shadowing/Mirroring/Duplexing
RAID level 1 refers to maintaining duplicate sets of all data on separate disk drives. Of the RAID levels, level 1 provides the highest data availability since two complete copies of all information are maintained. If one of your hard drives fail, you will have an exact copy of all your data on your other hard drive, meaning that you can carry on working as normal without having to restore lost files. You could see it as having a permanent automatic back-up of all your data. Even if one hard drive fails, you can then use the other hard drive to create a new RAID array and so in theory (unless you have an electrical surge, or both hard drives fail simultaneously) you can never be caught out when you turn on your computer one day to find that your hard drive has failed.
Advantages:
Excellent data availability
Higher read performance than a single disk
Disadvantages:
Expensive - requires two hard drives (if you order 2 x 1TB, you will only have 1TB total storage space and not 2TB)
Summary
RAID 0 requires two hard drives. Data is written to both hard drives (part of the data on one hard drive, and part of the data on the other) to give faster write times and also faster read times. Hard drives act as one drive - e.g. one large 2TB hard drive consisting of 2 x 1TB hard drives. However, if one hard drive fails, the array will be broken and all data will be lost.
RAID 1 requires two hard drives. Data is written to both hard drives simultaneously (files are written in full to each hard drive) and therefore you will have an automatic back-up should your hard drive ever fail. However, this security comes at a cost - two hard drives are required and you can only fill one hard drive, (as the other will be automatically filled as you go along) but for some people the added security is well worth the extra cost.
To learn more about RAID, please see this very useful website here:
http://linux.cudeso.be/raid.php#raid1
Please note that we only offer RAID 0 and RAID 1 configurations, and have no plans at present to change this. |
) on the right hand side of the configurator.
