Use the RAID Calculator to calculate the RAID capacity and get assistance in RAID planning.
| Selected: 0 |
|---|
| Select |
| Select |
| Select |
| Select |
| Select |
| Select |
| Select |
| Select |
| Reset All |
| Selected: 0 |
|---|
| Select |
| Select |
| Select |
| Select |
| Select |
| Select |
| Select |
| Select |
| Reset All |
More Tools
RAID Calculator helps in RAID assistance. The tool is a disk space utilization calculator that calculates capacity, data protection, and unused space characteristics for RAID 0, RAID 1, RAID 5, RAID 6, RAID 10, RAID 50, and RAID 60.
The tool will help you calculate the fault tolerance characteristic in different RAID levels.
To use the RAID disk space utilization calculator, perform the following steps.
Would you be interested in more Dev Tools in DNS Checker? Why do not you try our Binary to Text, Open Graph Checker, SMTP Test Online, and MD5 Online? They all are top-notch and free!
Previously, mainframe computers used large and expensive hard disks designed to manage data promptly. But that structure had a drawback if it failed; the overall system would collapse and lose all the data (unless you had the backup). Therefore, the expensive disk would need to be replaced.
With time cheaper hard drives came into the market, but they needed more reliability, with failure being all too common. So what was the solution?
The solution is RAID.
RAID stands for Redundant Array of Inexpensive Disks or Redundant Array of Independent Disks. It's a logical way of arranging the disks in an array (using many disks together, acting as one). The logic behind that structure is to use several cheap hard disks to get the speed and reliability of an expensive disk.
Depending on your desired speed and reliability, there are many ways to configure and arrange those inexpensive hard disks. But the exact speed and reliability you will get from RAID depend on your selected RAID level.
In RAID 0, the data is broken into blocks and written alternately to each RAID hard disk. Suppose you have two disks, Disk 0 and Disk 1. The odd-numbered blocks will be written on Disk 0, and even-numbered blocks will be written on Disk 1. The process is called striping. The performance is doubled because reading and writing can happen simultaneously. An individual file can use the speed and capacity of all the disks of an array, resulting in a significant increase in performance as you read and write from multiple disks simultaneously.
But there is also a drawback that RAID 0 is NOT redundant. If even one disk fails, you will lose all of your data.
RAID 0 is an excellent choice for high performance and data elsewhere. For example, you can use this in a severe environment for caching purposes, where you need fast speed, but data reliability or loss is fine.
In RAID 1, the data is mirrored on each hard disk. Suppose one disk fails, and the second disk has the data backup. That RAID level is all about reliability and fault tolerance. However, in performance, RAID 1 is nowhere near RAID 0 as writing performance will be the same because writing the same data on both drives simultaneously. But the reading performance would be slow. However, as per theory, that will be the sum of the speed of two disks.
To maximize the performance, carefully select the RAID hardware and software. You can add more disks, but it will increase the cost per usable capacity. Suppose you have three mirrored disks; if two fail, you still have the last one to avoid data loss. However, the total usable space would only be a third of the entire capacity of all hard disks.
In RAID 5, the data is striped into several disks, like in RAID 0. But a parity data block is efficiently written on an extra hard disk to make it fault-tolerant and redundant.
In RAID 5, you require a minimum of three hard disks. Suppose one disk fails. You can recover the data by using the rebuilding process, where the parity data is used to recover the lost data in conjunction with the remaining data.
However, rebuilding the RAID array requires a lot of time and severe sacrifice of performance. Once you replace the failed disk, it will need a significant array's performance to rebuild the data from the parity information. It does not compare well with today's enormous hard disks and could take hours or days to complete. During the rebuilding operation, the array will be at risk of another disk failure, which would mean a total data loss.
RAID 6 is an extended version of RAID 5, where you use a second parity block means it includes double parity. That allows two disks to fail without any data loss. In RAID 6, you require a minimum of four hard disks. Suppose one disk fails, which causes the data to rebuild. If another disk fails, there is still no data loss. That means RAID 6 is twice the fault tolerance of RAID 5.
RAID 10 uses the concept of mirroring and striping. In RAID 10, you require a minimum of four hard disks, the set, or two or more mirror disks striped together. That means RAID 10 allows two disk failures, one per mirrored set.
In RAID 50, several RAID 5 arrays are striped together. That means one disk per sub-array can fail without any data loss. In RAID 50, you require a minimum of six hard disks.
In RAID 60, several RAID 6 arrays are striped together. That means two disks per sub-array can fail without any data loss.
RAID 10, RAID 50, and RAID 60 are nested RAID levels. In RAID 60, you require a minimum of eight hard disks.
Following are the minimum number of disks required to be each RAID type:
You require NO RAID when you can endure several hours of downtime and bear data loss while your site recovers from data backup.
RAID is beneficial when uptime and reliability are the essential metrics of your business. Backups are necessary because they help from severe data loss. But restoring a large amount of data even takes several hours or days in any disk failure. RAID protects you from data loss without downtime in case one or more disks fail.
However, you require RAID 0 when you need high performance and speed; data loss or reliability is not essential for your business. On the other hand, RAID 1 provides you with inexpensive gain, additional data redundancy, and read speeds.
RAID 5 or RAID 6 is essential when you have web servers, high-read environments, or massive storage arrays as a single object. However, the RAID 10 is the most suitable if you need fault tolerance but want fast rebuild time. It provides additional read and writes speed as well as additional redundancy.
Note: Regarding disk capacity, one gigabyte equals one billion bytes, and one terabyte equals one trillion bytes. However, your computer's operating system may use a different measurement standard and display lower capacity. In addition, some of the listed capacities may use for formatting and other functions and may not be available for data storage.
