RAID stands for Redundant Array of Independent Disks (or, alternatively, Redundant Array of Inexpensive Disks). It’s a technology that allows multiple hard drives or solid-state drives to function as a single volume.
The primary advantage of RAID is right in the name: It’s redundant, which means that data exists in multiple places at once. In other words, if you write a file to a true RAID, a hard drive failure will not cause permanent data loss — provided that the RAID can be successfully rebuilt — and the system can continue operating.
For personal computer users, a RAID 10 is an especially attractive option. Below, we’ll explain how a RAID 10 operates and outline the advantages and disadvantages of this type of storage system.
What is a RAID 10, and how does it improve data reliability?
A RAID 10 is a type of nested RAID. Nested RAIDs are also known as hybrid RAIDs; they combine two or more standard RAID levels to improve performance or redundancy.
RAID 10 basically means a RAID 1, plus a RAID 0. Here’s how those two RAID levels function:
- A RAID 0 stripes data across all drives. As a very simple example, if you write a file to a two-drive RAID 0, half of the file might exist on each of the two drives. RAID 0 may provide improved performance over a single hard drive, since the system can write data to two hard drives at once — but unlike other RAID levels, RAID 0 is not redundant. For that reason, it’s not a true RAID.
- A RAID 1 mirrors data across all member drives. If you write a file to a two-drive RAID 1, the file would exist identically on both of the two drives. RAID 1 provides redundancy, but does not provide any of the performance improvements of other RAID levels (writing data to a RAID 1 takes as much time as writing data to a single hard drive or SSD).
RAID 10 provides a sort of “best of both worlds:” It’s a RAID 0, but with a 1:1 mirror via a RAID 1. If a single drive fails, it can be replaced. It’s also fairly easy to set up and maintain, which makes it preferable to RAID 5 for certain purposes.
What are the disadvantages of RAID 10?
RAID 10 combines basic mirroring and striping, which makes it a high-performance, high-reliability option, particularly for home computer users. However, it can only accommodate a single hard drive failure within a mirrored volume. Other RAID levels may provide a greater degree of redundancy.
Additionally, RAID 10 is not conservative in terms of media usage. If you want to store 1 terabyte of data, you need to use 2 terabytes of storage — and if you’re storing an extremely large amount of data, the cost of physical media can add up.
The bottom line: RAID 10 is an excellent option for personal computer users who need to store a large amount of data redundantly. It’s fairly easy to set up, and ready-to-use RAID 10 devices are commercially available. However, for large-scale data storage, options like RAID 5 may provide better performance and reliability at a lower cost.
Do I still need to back up the data on my RAID 10?
You must still back up redundant systems. RAID is not backup; while it improves the integrity of your data, it’s not perfect. Data loss is always possible:
- If the RAID’s controller card fails or a rebuild is handled incorrectly, you can lose data.
- If the system is impacted by a natural disaster, you can lose data.
- If you accidentally delete a file, you can lose data.
- If the system is infected by ransomware or other malware, you can lose data.
With that said, a RAID system can reduce your chances of permanent data loss when paired with an appropriate backup strategy.
I’ve lost data from a RAID 10. What should I do?
RAID 10 data loss is uncommon, but certainly not impossible. If you’re unable to access files stored on a RAID 10 device, follow these steps:
- Power down the device. Do not attempt to rebuild the array before fully assessing the situation.
- Make a list of any symptoms that preceded the failure, including error messages, indications of hard drive crashes (unusual noises, etc.), and a thorough description of your RAID 10 (brand, file system, and so on).
- Contact a professional data recovery provider. Look for a firm with RAID experience and make sure that they operate real laboratories.
- Follow your data recovery provider’s instructions for shipping or transporting the RAID.
Datarecovery.com provides expert services for all RAID levels, with full support for all controller cards and hardware. We also provide risk-free evaluations for RAID 10 units, and all cases are supported with our no data, no charge guarantee: If we’re unable to recover the files you need, there’s no charge for the attempt.
To learn more, set up a case online or call 1-800-237-4200 to speak with an expert.
