Redundant Array of Independent Disks (RAID)

What is RAID (Redundant Array of Independent Disks)?

RAID or Redundant Array of Independent Disks refers to a collection of hard drives set up and connected together to enhance the performance of disk storage and offer additional protection to the stored data, offering fault tolerance.

Understanding RAID (Redundant Array of Independent Disks)

What is RAID

RAID is a data storage virtualization technology where several physical disk drives are combined to form a logical unit or units for data redundancy and performance enhancements.

It basically stores the same data on different disks and places. These drives work in parallel. This prevents data loss in the event of a drive failure.

The connected disks are called the array members and are combined using different RAID levels.

The RAID systems use different interfaces such as:

Input/output operations are overlapped in a RAID system in a balanced way and the array appears as a single drive to the operating system.

RAID Levels

Typically, the RAID levels are categorized as standard RAID levels, non-standard RAID levels, and hybrid or nested RAID levels. There are RAID 0, 1, 2, 3, 4, 5, 6, 53, 0/1, and more, though some of them are not used today.

Here are the standard and commonly used RAID levels.

RAID 0: Striping

Also known as a striped volume or striped set, RAID 0 can be done with two drives only. This specific level is characterized as follows:

Raid 0 should be used when:

RAID 1: Mirroring

RAID 1 also needs at least two drives to store the same data on them and ensure redundancy. It is commonly used to create a mirrored pair of one disk on the other, which is why it is also known as mirroring.

This specific RAID level can be characterized as follows:

Raid 1 should be used when:

Raid 5: Striping with Parity

RAID 5 is one of the most commonly used RAID levels and is also considered to be the most secure of all RAID implementations. It can be characterized as follows:

Raid 5 should be used when:

Raid 6: Striping with Double Parity

RAID 6 is quite similar to RAID 5, but with an additional parity feature. This is why it is also called the double-parity RAID and is characterized as follows:

Raid 6 should be used when:

Raid 10: Mirroring with Striping

Also known as RAID 1+0, RAID 10 is a hybrid or nested type of RAID configuration where there are two different levels combined into one. It can be characterized as follows:

Raid 10 should be used when:

Non-standard RAID:

These are the RAID configurations created by different companies and open-source projects according to their needs. Hence, these are non-standard RAID implementations. Some of these implementations are:

Nested (Hybrid) RAID:

These RAID configurations are designed by combining two or more standard RAID implementations to offer higher redundancy and performance.

These RAID implementations are named according to the RAID levels combined. There are usually two digits in the order of the layering scheme.

Some of the popular hybrid or nested RAID levels, including RAID 10 mentioned above, are:

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Do You Need RAID on Your PC?

Yes, you will need RAID on your computer because it is extremely useful for protecting your data. You should use it all the more if availability and uptime are two vital things for you.

RAID is also useful when you face IO issues with your hard disk resulting in long waits for it to complete a given task. You will be able to read and write from other drives instead of adding one to the output.

Moreover, if you have hardware RAID, the card will have additional memory to use as cache. This will also reduce the workload on the physical hardware of the computer to increase its overall performance.

However, you may not opt for using RAID if you are okay with data loss or several hours of downtime while restoring your site from the backups.

There are different types of RAID configurations that you can use such as:

How to Set Up a RAID?

The process to setup RAID is pretty simple and will vary a bit depending on the specific type of RAID you want to set up.

Typically, you can set up RAID 5 for redundancy and efficiency or the nested RAID 10 system for sheer performance on your Windows 10 by using the System Settings.

To setup RAID 5, you will need three drives for parity and striping and to follow these steps:

To set up a nested RAID 10 system, you will need four drives for mirrored striping and to follow these steps:

To create the second mirrored drive pair, repeat the same steps. You may create as many as you want by following the same process.

Now, press Windows and X at the same time to open Windows Disk Management and follow these steps:

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To complete the process, click on the prompt, if any, and wait until Windows completes formatting the new volume.

Based on where the RAID process takes place, the implementation process may also vary.

For example, for a hardware-based RAID installation, you can use a RAID controller card and insert it into a fast PCI Express slot on your motherboard to connect it to the drives.

For a software-based RAID setup, you will need to connect the drives to the computer system directly instead of using a RAID controller.

The disks, in this case, need to be managed by a utility software on the operating system.

And for a firmware- or driver-based RAID, it hardly needs any separate setup since it is stored on the motherboard directly.

All of its operations are carried out by the CPU of the computer and not by a dedicated processor.



Questions & Answers:

Is RAID a Backup?

Ideally, you should not consider RAID as a backup, even though it offers additional data protection.

Therefore, make sure you have a proper backup of your data, even if you use RAID. It will save you from any catastrophic data loss.

Which RAID Is Most Commonly Used?

Usually, RAID 5 is the most commonly used RAID configuration. The main reason for this is its data striping utilization.

It involves separating data into segments and storing them on different disk drives in the array.

Where Is RAID Commonly Used?

RAID is most commonly used in servers but is also used in high performance computers, including desktop and laptop computers. Floor-standing RAID units are also used in large Storage Area Networks (SANs).

Which RAID Is Best for Storage?

Different levels of RAID will offer different benefits, but if you are looking for high performance from your storage systems, you should opt for RAID 0.

This offers fast read and write speeds, along with a lot of raw storage capacity.

The best thing is that RAID 0 will not provide any data redundancy, which is commonly associated with RAID, thereby enhancing its performance level.

How Many Drives Are Required for RAID?

You will need a minimum of three drives to set up RAID on your computer. This helps RAID sustain the loss in the event of one drive failing.

In such a situation, the data from the defunct drive will be reconstructed on the remaining drives using parity stripes. However, for some RAID levels, you will need four drives, such as in RAID 10.

Is RAID Used in Laptops?

Usually, RAID is used on servers. However, it has also been used recently in high-performance laptop computers as well as desktop PCs for more efficient distribution of data on the disks.

Do Motherboards Have RAID?

Yes, most of the motherboards today have RAID built-in, but that does not mean every motherboard will support the same RAID configuration.

Typically, RAID uses a specific controller and two or more physical drives. These are typically connected to motherboards that do not come with RAID circuits.

Does RAID Use CPU?

Yes, hardware RAID will typically use a general-purpose CPU, which is commonly a Power or an Advanced RISC processor.

It may even use a custom Application Specific Integrated Circuit (ASIC) to handle the latency introduced in order to prevent the drop in the output.

Ideally, the latency will vary depending on the processing capacity of the system.


RAID is a very useful and efficient way to store and protect your data by storing the same data on separate hard disks and SSDs.

Since there are multiple disks containing the data, you will not suffer any data loss if one particular drive on your computer fails.

There are many levels of it but all do not provide redundancy.