Photo: There are a bunch that RAID levels, for this reason many, in fact, the it have the right to be a challenge to distinguish in between the differences and benefits that each. In this blog post, we"ll talk about a few common RAID levels, highlighting both your differences and benefits.

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When selecting a RAID level for your storage array, it’s important to take into consideration what you value most: speed, fault yongin or both.

In this blog post, we’ll testimonial five usual RAID level - RAID 0, RAID 1, RAID 5, RAID 6 and also RAID 10 - and how every levelstores data.

And if you"re interested in a made-in-USA rugged storage system that deserve to utilize this RAID types, don"t hesitate come drop us a heat to learn an ext about what we have the right to do for you.


We’ll likewise briefly evaluation software RAID vs. Hardware RAID, as well as the history of the RAID modern technology itself.

By the end, you must be ready to rock ‘n RAID.

Table the Contents


Photo: A Trenton solution JBOD/JBOF rough Storage unit. The 24 NVME SSDs on this unit can be RAID-configured for far better performance and also a higher degree of error tolerance.

What is RAID storage?

Redundant range of elevation Disks (RAID) is a storage modern technology that create a data loss fail-safe by merging two or much more hard disk cd driver (HDDs) or solid-state cd driver (SSDs) into one cohesive warehouse unit, or array.

RAID storage protects versus the complete loss of a decaying drive’s data by repeating or recreating that data and storing it on the added drive or drives, a procedure also known as data redundancy.

Total data loss, i m sorry may take place in the event of a disk drive failure, can devastate businesses and also organizations that require frequent accessibility to stored info to bring out their daily responsibilities.


Graphic: consequences of disk journey failure in mission-critical applications

Total data loss have the right to be especially terrible for mission-critical applications, through which a potential fail could result in financial loss, windy disapproval, serious injury and even death.

Thanks to RAID, mission-critical personnel can proceed focusing ~ above executing their crucial duties without having to worry about the possibly dire ramifications of a disk journey failure.

But together you’ll see, no all levelsof RAID storage protect versus data loss. In fact, there’s just one that doesn’t.

Configurations that sell data loss defense are described as “fault-tolerant.” This just way that the variety will continue to function successfully and provide recoverable data in the event of a disk journey failure.


Graphic: software application RAID vs. Hardware RAID. Difficult drive symbol made by Surang in ~ Flaticon

RAID Types: software application RAID vs. Hardware RAID

Implementation and management that RAID storage deserve to be enforcement via software RAID, by which a driver top top a computer system executes RAID processing, or by hardware RAID, whereby a RAID controller card utilizing a motherboard’s PCI express slot is used.

The performance of software RAID counts on the handling power that the computer. The not ideal for facility RAID configurations.

For those high-performance configurations, you’ll need a committed RAID controller, the sole purpose of i m sorry is to execute RAID processing.

Average desktop computer users can get by with software application RAID, because most operating systems, consisting of Apple and also Windows, assistance RAID. Plus, software RAID is the cheaper option.

Bigger, more complicated RAID applications, however, will have to go through hardware RAID to achieve the highest feasible performance.


Graphic: computer system scientists Dave Patterson, Garth Gibson and Randy Katz. The trio is credited with coining the RAID acronym and also sparking commercial interest in the technology. Credit: Computer history Museum

History that RAID

The acronym “RAID” was coined by university of California, Berkeley computer scientists David Patterson, Garth Gibson and also Randy Katz in their research study paper, “A instance for RAID,” presented at the 1988 yearly conference that the association for computer Machinery’s one-of-a-kind Interest group on administration of Data (SIGMOD).

RAID initially stood because that “Redundant range of inexpensive Disks” as result of the expense factor of Patterson, Gibson and also Katz’s paper.

The trio said that one range of multiple cheap disks can technically outperform your larger, much more expensive counterpart: the mainframe disk drive.

Although the concept of combine disk cd driver to boost performance wasn’t a new one, the trio’s file sparked commercial attention in RAID.

Several RAID level have since been standardized by the warehouse Networking industry Association (SNIA).

Configurations are generally evaluated based upon their level of error tolerance, their read and write speeds and also their warehouse capacity.

There are countless RAID levelsin usage today, number of of which space rare.

The most usual RAID configurations space RAID 0, RAID 1, RAID 5, RAID 6 and also RAID 10.


Graphic: RAID 0 configuration

What is RAID 0?

RAID 0, the simplest RAID storage design, uses data striping, a process that separates records into segments for storage.

The data segments are stored top top one disk drive, and the other disk cd driver in the array.

A RAID 0 setup boosts a decaying drive’s read and write speeds, given that the extr drives add concurrently come the array’s overall read/write workload.

For example, if you’re storing a 1GB record in a two-disk RAID 0 configuration, the 1GB paper is separated into two 500MB segments before being written onto each disk, cutting write time in half.

Read time is likewise cut in half, due to the fact that retrieving the 2 500MB data chunks from 2 disks takes much less time 보다 retrieving the whole 1GB document from one disk.

So, essentially, the more disks in the RAID 0 array, the much faster the read and write speeds.

Now, why can you want to use a RAID 0 decaying configuration?

RAID 0 is good for storage applications that require swift read and also write speeds and also have a fairly low danger of full data loss.

It’s perfect for computer gamers, who normally prefer shorter save and load times, as well as photographers, videographers and also music producers, who frequently save and also load big files using modifying software.

Unfortunately, RAID 0 lacks data redundancy, ergo, the is not a fault-tolerant array. If one of the disk cd driver in the array fails, all the data is lost.

In various other words, RAID 0 need to be avoided choose the torment in mission-critical applications, where a complete loss that data could have catastrophic consequences.

An added plus, however, is the RAID 0 users have the right to utilize the entire capacity of the disc drives. So, if you using 4 1TB disk cd driver in her RAID 0 array, girlfriend have access to 4 TB that space.

This is no the instance in the other typical RAID configurations, whereby duplicate data chunks are developed to boost fault tolerance, and as a result, take it up much more space.


Graphic: RAID 1 configuration

What is RAID 1?

RAID 1 uses disk mirroring, i m sorry creates duplicates of the same record for storage.

In RAID 1, the original paper is save on computer on one decaying drive, and identical duplicates of the paper are save on the other disk drives in the array.

As a result, RAID 1 produce disk drives that are mirrored duplicates of every other.

Unlike RAID 0, RAID 1 offers data redundancy, developing a fault-tolerant array.

So, in a two-disk RAID 1 configuration, if one disk journey fails, the 2nd disk drive consists of the very same data, ergo, data was not lost and can be easily recovered. Together a result, error tolerance has been achieved.

Similarly, in a five-disk RAID 1 configuration, if three disk cd driver fail, the fourth and fifth disk carry out users with two finish backups of the exact same data.

The an ext disk cd driver in the array, the much more copies that the records that space created, and also in turn, the better the degree of error tolerance.

RAID 1 is advantageous for mission-critical applications, where complete loss the vital, perceptible or share data is unacceptable.

Doctor’s offices, accounting firms, regulation firms, banks, police departments, wellness departments and also other federal government offices could all advantage from a RAID 1 warehouse configuration.

But even average, daily users can advantage from RAID 1’s data cloning abilities.

The gamers, the photographers, the videographers and also the music producers, each of whom would undoubtedly benefit from the increased read and write speed of RAID 0, would certainly arguably be better off sacrificing the speed of RAID 0 for the data redundancy and also fault yongin of RAID 1.

RAID 0 vs. RAID 1

When deciding in between RAID 0 and RAID 1, the RAID 1 users deserve to take comfort in discovering that, in the occasion of a disk drive failure, their papers have been safely duplicated.

RAID 1 data has actually not been segmented, therefore if a disk journey failure occurs, the data execute not need to be pieced back together from the fail disk and also are therefore recoverable.

RAID 1 must not replace regular backups, however.

Another fence of the standard two-disk RAID 1 configuration is the its storage capacity is only fifty percent of its full disk drive capacity.

So, if you’re using two 2TB disk drives, for a total of 4TB of storage capacity, you technically gift allotted 2TB of room because the 2nd drive includes the very same data as the first.

Now, if you include a 2TB disk drive to that very same RAID 1 array, she still only being allotted 2TB of space, because now, the various other two 2TB disk cd driver contain the very same data as the first.

And in a four-disk RAID 1 range with, because that example, 2 2TB decaying drives and two 4TB disk drives, because that a total of 12 TB of storage capacity, you still only being allotted 2TB the space.

Why? because if you’re conserving 2TB the data come the array, the 2TB drive is filled v the initial data, the 2nd 2TB is fill with duplicates of that data, and the 2 4TB drives have been fill with duplicates at only fifty percent of the drives" usable storage capacity.

So, in this setup, you’d have 6TB being offered for data protection and also 4TB that unused space.

Compare each of this scenarios to a RAID 0 configuration, in which the array’s warehouse capacity would certainly be identical to the complete disk journey capacity.

The trade-off because that RAID 0 is fault tolerance, and also the trade-off because that RAID 1 is speed and efficiency.

This RAID ingredient can obtain rather complex, huh? Well, friend haven’t watched anything yet!

Be certain to inspect out Synology’s RAID storage calculator to check out various RAID arrays and also storage combinations.


Graphic: RAID 5 configuration

What is RAID 5?

RAID 5 is probably the most common RAID configuration, and unlike RAID 0 and also RAID 1, calls for a minimum of 3 disk cd driver to function.

RAID 5 uses data striping, by which data space separated into segments and stored ~ above the different disk drives in the array.

But RAID 5 also utilizes a procedure called parity, through which a checksum of all the data is created and also stored onto each of the drives in the variety as well.

So, in a four-disk RAID 5 array, the data and their parity checksums would be striped and distributed top top all four drives because that safekeeping.

And in the event of a disk drive failure, the same checksums allow for the recreation that the stored data.

The fence to RAID 5 is that it have the right to only withstand one disk journey failure.

Thankfully, RAID 5 is hot-swappable, definition one disc drive have the right to be replaced while the others in the range remain completely functional.

Unfortunately, if a second disk drive stops working while the data indigenous the first is being recreated, then all the data in the range are lost.

In regards to storage capacity, due to the fact that the room of one disk drive is required to store the parity checksums, total variety storage capacity in RAID 5 configurations is diminished by one totality drive.

For example, in a five-disk RAID 5 construction with 5 1TB decaying drives, for a complete of 5TB of warehouse capacity, only 4TB have the right to be utilized due to the fact that the same checksums take up the an are of one entirety disk drive.

Similarly, in one eight-disk RAID 5 configuration v eight 2TB decaying drives, for a full 16TB of warehouse capacity, just 14TB have the right to be utilized.

RAID 5 outshines RAID 0 and RAID 1 in terms of fault tolerance and also has greater total warehouse capacity than a RAID 1 array.

Like RAID 0, RAID 5 check out speeds are fast due the concurrent calculation contribution of each drive, however unlike RAID 0, the create speeds the RAID 5 suffer as result of the redundant development of the same checksums.

RAID 5 v. RAID 6

RAID 5 and also RAID 6 room not so different. Lock both use the data striping and parity processes.

The key differences between the two configurations space that RAID 6 requires 4 drives to function, and also it utilizes dual parity, by which two checksums are created instead that one.

In RAID 6, 2 disk drives can fail without total data lose occurring. This means better security 보다 RAID 5, but it also way even slower write speeds since one extr checksum need to be created.


Graphic: RAID 10 configuration

What is RAID 10?

RAID 10 uses both data striping and also disk mirroring to achieve data redundancy and also thus a high level of fault tolerance.

RAID 10 is periodically referred to together “RAID 1+0,” because it combine the mirroring and striping processes found in the RAID 1 and RAID 0 configurations, respectively.

In a RAID 10 configuration, which needs a minimum of 4 disks, data is segmented prior to being replicated onto the drives in the array.

Like in RAID 0, wherein a document is segmented and stored onto two separate disk cd driver in a two-disk configuration, in RAID 10, each of those document segments are mirrored, requiring extr storage space.

A traditional four-disk RAID 10 setup deserve to only withstand one drive failure in each mirrored pair of decaying drives.

Otherwise, complete data loss occurs.

And similar to the traditional two-disk RAID 1 configuration, full storage capacity of RAID 10 is halved. So, six 1TB disk drives will just net friend 3TB the usable space.

Indeed, RAID 10 is the ideal of both RAID 0 and RAID 1, boasting fast read and also write speeds and also incredible error tolerance.

RAID Configurations: Processes and Fault Tolerance
Raid LevelRaid 0Raid 1Raid 5Raid 6Raid 10
ProcessData StripingDisk MirroringStriping + ParityStriping + double ParityMirroring + Striping
ToleranceNot Fault-TolerantFault-TolerantFault-TolerantFault-TolerantFault-Tolerant

Which RAID is best?

The finest RAID configuration for her storage device will rely on whether you worth speed, data redundancy or both.

If you worth speed most of all, select RAID 0.

If you worth data redundancy most of all, remember that the complying with drive configurations space fault-tolerant: RAID 1, RAID 5, RAID 6 and also RAID 10.

Determine her RAID goals by reviewing the adhering to scenarios:

Q: are you a large business or organization with many servers and also numerous employees who require consistent accessibility to the data save on computer on those servers?

A: choose RAID 5, RAID 6 or RAID 10, and go through a hardware RAID controller.

Q: space you a little business or organization where rate isn’t as much of a priority as appropriate record-keeping?

A: select RAID 1 or RAID 5, and also choose your operating system’s software program RAID driver.

Q: room you a mission-critical business or company where a ns of sensitive, share or various other vitally important data could result in headache, gaue won ruin, serious injury or even death?

A: select RAID 6 or RAID 10, and also choose a hardware RAID controller.

Q: room you a gamer, photographer, videographer, music producer or other user who worths speed and efficiency over fault tolerance?

A: pick RAID 0 through your operation system’s software program RAID driver. Yet be sure to conduct continual backups.


We expect this blog write-up helped work out the differences between common RAID levels and how every of them deserve to offer a unique benefit to your program or application.

Trenton equipment manufactures customizable rough storage systems that can utilize RAID technology. These systems incorporate our JBOF/JBOD and also 5U rough Storage systems.

Not just do we market RAID-capable rough storage systems, yet we design, manufacture, assemble, integrate and also support these equipment right here in the unified States. That"s right. We execute it every in one USA basic to provide you through high-quality rugged computing solutions, reduced down on potential protection hazards, support the American economy and American jobs, and offer super fast, in-house client service and support.

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Trenton equipment creates rugged computer systems to assist customers around the world meet your rugged computer needs. We stress-test our computer system systems to the max, ensuring the customers can bring out industry-specific to work comfortably, effectively and also smack dab in the middle of the world"s harshest conditions. In various other words, we stress so you don"t have actually to.