Using the technology known as RAID (Redundant Array of Independent Discs), several physical disc drives can be combined into a single logical unit. It is intended to enhance the performance, dependability, or both of data storage. Depending on the RAID level used, RAID offers improved data access speeds, fault tolerance against disc failures, or a combination of both advantages by distributing or replicating data across several discs.

There are various levels of RAID setups, and each one has special capabilities that are appropriate for certain storage scenarios and requirements. For optimum efficiency and data redundancy, these levels span from straightforward striping methods to intricate combinations of striping, mirroring, and parity.

In this extensive blog, we will look at the different RAID levels, their characteristics, advantages, and applications. Understanding RAID technology can aid with data management strategies in a range of computing settings, from commercial servers to home storage devices.

What is RAID

Redundant arrays of independent discs, or RAIDs, are a way to store the same data in many locations across multiple hard drives or solid-state drives (SSDs) to protect data in the case of a disc failure. However, not every RAID level aims to offer redundancy; some are not the same as others.

How RAID Works?

Let's comprehend RAID's operation with an illustration Say you wish to protect your favorite book from harm and you have a large group of friends. You make duplicates of the book and give a bit to each buddy rather than giving the entire book to one person. You can still assemble the book using the remaining pieces even if one of your friends loses their piece. That is comparable to how hard drive RAID functions. Your data is divided among several drives, so even in the event of a disc failure, it is still safe on the other drives. RAID keeps your data safe in the same way that lending your best book to friends does.

RAID Controller 

A RAID controller is your hard drive's superior in a big storage system. It acts as a go-between for your computer's operating system and the hard drives, organizing them for simple management. This gives your computer faster read and write speeds and adds a layer of protection in case one of your hard drives fails. It works like a smart assistant, protecting your private data and enhancing the efficiency of your hard drives.

Types of RAID Controller

There are three types of RAID controller  

• Hardware Based 
• Software Based 
• Firmware based

Hardware Based 

A physical controller oversees the entire array when using a hardware-based RAID. This controller can be used to control the full set of hard drives. It is designed to work with a variety of hard drive types, such as SATA (Serial Advanced Technology Attachment) and SCSI (Small Computer System Interface). Sometimes, having this controller built right into the computer's main board makes setting up and maintaining your RAID system easier. It works like a captain guiding your group of hard drives and making sure they work together seamlessly.

Software Based 

In a software-based RAID, the controller is devoid of specialized hardware. It consequently runs on the machine's primary CPU and RAM. It functions similarly to a hardware-based RAID controller in terms of managing the hard drives and protecting your data. However, performance can be affected because it's sharing resources with other programs on your computer. As such, the speed benefits it offers may not be as large as that of a hardware-based RAID system, even if it is still beneficial.

Firmware based

Firmware-based RAID controllers are comparable to the helpers found on a computer's motherboard. They rely on the primary CPU, just like software-based RAID. But they are only active during the machine's bootup. RAID is managed by a particular driver once the operating system has started. These controllers place more strain on the computer's primary CPU even though they cost more than their hardware counterparts. They are sometimes referred to as hardware-assisted software RAID, hybrid model RAID, and fake RAID.

RAID Pros 

A few pros of RAID are as follows.

• An increase in cost-effectiveness as a result of the widespread adoption of less expensive discs.
• RAID makes it possible to increase a single hard drive's performance by using numerous hard drives.
• Depending on the setup, faster and more dependable computers following crashes.
• RAID 5 offers greater resilience and availability. RAID arrays can include two discs with identical data when mirroring is used. It guarantees that if one fails, the other will still function.

RAID Cons 

The following are the Cons of RAID

• Because nested RAID levels require many discs, its implementation is more costly than that of regular RAID levels.
• Because many of the drives are utilized for redundancy, nested RAID has a greater cost per gigabyte of storage devices.
• The likelihood that another drive in the array would fail soon after a drive fails increases, which could lead to data loss. This is a result of a RAID array's drives being deployed all at once. For this reason, the wear on each drive is equal.
• RAID 1 and 5 are examples of RAID levels that can only withstand a single drive failure.

RAID Technology and its Various Modes 

RAID 0: Striping

RAID 0 improves performance by allowing simultaneous read and write operations across all of the array's discs by dividing data evenly over numerous discs. Because of the enhanced throughput and shortened access times that result, it is ideal for high-speed data transmission applications such as video editing and gaming. However, RAID 0 lacks fault tolerance, making the entire array susceptible to failure and possibly leading to data loss. It is typically used when performance is the top concern and data redundancy is less significant. 

RAID 1: Mirroring

RAID 1 provides data redundancy by mirroring identical copies of the data over two or more discs. Since the data is exactly replicated on every disc in the array, access to the data can still be obtained through the mirrored copy even in the case of a disc failure. Great fault tolerance and read performance are offered by RAID 1 since data can be read from any of the mirrored discs. Write performance is similar to a single disc because all mirrored discs must have data written to them simultaneously. Operating system discs and servers hosting large databases, where data availability and integrity are critical, are common places for it to be stored. 

RAID 5: Striping with Parity

RAID 5 strips data across many drives and, like RAID 0, distributes parity information among all of the discs. The parity information of the surviving discs can be used to reconstruct the lost data in the event of a disc failure. Data recovery and error checking both employ parity. Performance and fault tolerance are successfully balanced by RAID 5, even though it needs a minimum of three discs. It provides improved read performance and moderate write performance, making it suitable for applications such as file servers and online transaction processing (OLTP) systems where speed and cost-effective redundancy are critical. 

RAID 6: Striping with Dual Parity

RAID 6 delivers dual parity and enhances RAID 5 by incorporating a parity block. Consequently, if the array has up to two disc failures simultaneously, data loss is avoided. RAID 6 is suitable in large-scale storage systems and archive solutions, for example, as it offers excellent data protection and fault tolerance, even in the face of numerous disc failures. RAID 6 typically needs more discs than RAID 5 and performs somewhat slower on writes because of dual parity calculations. 

RAID 10 (RAID 1+0): Mirrored Striping

RAID 10 combines the capabilities of RAID 0 and RAID 1. It reflects data by first creating mirrored disc sets and then removing data from each of these mirrored sets.RAID 10 provides fault tolerance together with outstanding performance by combining the benefits of redundancy and striping. Four discs minimum are required, half of which are used for mirroring and the other half for striping. RAID 10 excels in situations where robust fault tolerance and exceptional read/write performance are required, such as database servers, virtualization platforms, and high-demand transactional applications. 

Takeaway

RAID storage could be useful for companies looking to grow their on-premise data infrastructure. Achieving a balance between disk-based and cloud storage system investments is crucial in the era of more hybrid computing. They provide the perfect ratio of hardware to virtualization, letting you expand without limitations.

RAID is a valuable and practical method to enhance server performance and prevent data loss. The best setup for your business depends on your priorities. It is important to thoroughly explore all options and benefits of this powerful tool and technique. Utilize the Server Colocation Free RAID Calculator to determine the necessary array capacity for your RAID configuration.