RAID 1 vs RAID 2 - Difference and Comparison
Increasing numbers of technology professionals, corporations, startups, and data-intensive users are transitioning to RAID storage for its superior advantages over traditional single-disk storage. RAID, standing for Redundant Array of Independent Disks, is a storage solution that utilizes specialized methods like striping, mirroring, and parity to manage data.
Various RAID configurations exist, each employing one or more of these specialized techniques. RAID setups can be built with either HDDs (Hard Disk Drives) or SSDs (Solid State Drives), but it's crucial not to mix these two types in the same RAID array. Consistency is key, so use either HDDs or SSDs exclusively in a single setup.
RAID 1 and RAID 2 are two notable configurations chosen based on specific storage needs. While there are similarities between these two configurations, they also have significant differences. This article aims to provide a detailed comparison and contrast between RAID 1 and RAID 2 setups.
However, it's important to remember that despite RAID's enhanced data protection and redundancy features, it is not a foolproof solution against data loss. Regular backups are still essential, regardless of the RAID level utilized, to ensure comprehensive data security.
What is RAID 1
RAID 1 is a type of RAID storage configuration where data is mirrored across all disks in the array, and as such, this RAID configuration is codenamed “Mirror RAID.” In this RAID storage, the same data is saved across multiple disks, which makes data still accessible even when one or more disks fail in the array.
To make this clearer, in a RAID 1 setup, when data is saved on Disk A, the same data will be replicated (with the same size and details) to Disk B, Disk C, and every other disk used in the array. All the disks will get the same exact data that was saved on the first disk. This might sound cool to many, but there are disadvantages to this RAID configuration.
You need just 2 disks to set up RAID 1, but you could still use as many as seven (7) or more disks if you wish. This makes RAID 1 an affordable option for quite many people looking for high redundancy – with less concern towards getting high read and write speeds.
Disadvantages of RAID 1:
- Less Storage Space: Since data is mirrored across all the disks, the total storage capacity in a RAID 1 setup is equal to the size of the smallest disk in the array (if different disks of different sizes were used). If disks of the same size were used, the total RAID storage capacity is as big as the total storage capacity of a single disk in the array.
- Poor Writing Speed: The total writing speed of RAID 1 is equal to the overall writing speed of the slowest disk in the array. If all the disks operate at the same speed, then the write speed is equal to that of a single disk in the array.
- Can Be Very Expensive to Set Up: You’ll literally have to buy hard drives with very high storage to set up a RAID 1 because there’s no room for storage expansion. Well, you could still use low-capacity drives if you don’t deal with tons of data.
Advantages of RAID 1:
- High Fault Tolerance (Redundancy): One huge benefit of RAID 1 is fault tolerance. In a RAID 1 setup, even when more than one disk fails, provided there’s still at least one good disk in the array, all your data will still be accessible. So you may have multiple failed disks in a RAID 1 setup and it’ll still function as though nothing has happened.
- Rapid Data Recovery: While this RAID type does not replace the need for backups, it allows you the possibility to immediately recover your data when multiple disks fail in the array at a go. This immediate data recovery is possible because the same data has been mirrored from the failed drives to the remaining good ones, over time.
Easy Installation: There’s no much configuration needed here, just arrange the disks into the array and the rest of the steps are intuitive. Compared to other RAID types, RAID 1 is seemingly easy to set up.
What is RAID 2
RAID 2 is a type of RAID storage configuration that supports data stripping in a different way from RAID 0. The technology utilized by RAID 2 is known as “Bit-Stripping,” a mechanism that allows data to be broken down into bits and spread across the entire disks used in the array. Unlike in RAID 1, once one disk fails in RAID 2, you may lose access to the complete version of all your files and data.
Well, this RAID type is currently obsolete due to its very poor data reliability. In RAID 2, data is stripped into bits and each of the bits is saved differently across the disks in the array. This RAID type also uses a “Hamming code” for error correction. Disks’ synchronization is handled by the controller – allowing the disks to spin at the same angular orientation. RAID 2 disks cannot run multiple requests simultaneously.
Actually, RAID 2 is the original RAID setup back in the days, but it is rarely used due to its complex setup procedure and data storage mechanism. However, it offers better speeds than RAID 1 and gives you more storage space.
Disadvantages of RAID 2:
- High Set-Up Cost: RAID 2 is pretty expensive to set up as it requires multiple disks and a variety of accessories to go along. You’ll be spending twice the amount you will use to set up a RAID 1.
- Not Fit For Modern Usage: This RAID type is not suitable for modern applications due to its complexity while still not offering high fault tolerance. Other RAID types offer much benefits than RAID 2. Also, most RAID 2 features are now inherent in modern hard disks.
Advantages of RAID 2:
- Hamming Code ECC: Apparently, the major offering of RAID 2 is the Error Correction Code (Hamming Code), which helps to detect and correct errors with the data bits stored across the storage drives in the RAID array to ensure accuracy when the data is been accessed.
- Seemingly High Data Transfer Rates: RAID 2 could possibly offer high transfer rates depending on the hamming code configuration.
Parity: Since data is spread in bits – striped across multiple disks, RAID 2 supports a dedicated parity disk where parity information for all disks in the array is stored. The parity information is fostered through Hamming code, and this provides a decent level of fault tolerance to be able to access your data when there’s a failed disk in the array.
Comparison Table RAID 1 vs RAID 2
RAID 1 and RAID 2 use different storage mechanisms and follow different setup procedures. Here’s a clear table comparison of these two RAID configurations.
Comparison | RAID 1 | RAID 2 |
Mechanism Used | Mirroring data | Bit-stripping with ECC |
Minimum No. of Disks | Two (2) | Four (4) |
Redundancy Level | Very high | Low |
Parity | High | High |
Use Cases | In various modern application | Currently obsolete |
Setup Cost and Complexity | Affordable, easy-to-install | Expensive, complex setup |
Performance & Speed | No significant increase | You may experience high performance |
Data Recovery Differences in RAID 1 vs RAID 2
First things first, setting up RAID does not substitute data backup. However, some RAID levels offer high redundancy, which means you can still access your data when one or more drives in the array fail. In this case, between RAID 1 and RAID 2, the former offers better chances for data recovery than the latter.
In RAID 1, your data will still be accessible until the last disk in the array fails completely. But this is not the same with RAID 2; in RAID 2, when one disk fails, it becomes difficult to recover your files in full. RAID 1 offers better data recovery chances over RAID 2 thanks to the mirroring data storage technique.
Notwithstanding, RAID 2 has its advantage over RAID 1. The Hamming Code error correction technique used by RAID 2 ensures data integrity at all times. With high data integrity potential, RAID 2 ensures you only access accurate information from the storage drives in the array.
So, basically, if you are looking for a storage configuration that will allow you enough time for data recovery in times of data loss, RAID 1 is actually the best. RAID 2 is already obsolete, you will hardly see anyone still using it today – so it’s not even advisable.
How to Safeguard Your Vital Data?
Over and again, it is worth noting that no RAID setup substitutes the need for regular data backups. The best thing a RAID setup could do for you is to offer high redundancy, a technology that allows you to still access your data when one or multiple disks fail in the array. So, in a scenario where all the disks fail at a go, your data and files will be gone forever.
Now, this is not to scare you, but to bring your memory afresh to the old saying, “A bird at hand is worth more than a million in the sky.” When you make local or cloud backups of your data, you have a reliable solace to fall on whenever your RAID fails. Interestingly, there are actually many software apps that allow you to back up your files for free.
It’s one thing to have a data backup solution, and it’s a whole different thing to keep up with making backups regularly. But well, there is always a solution to any “Problem,” for RAID data backup and recovery, DiskInternals RAID Recovery comes in handy, and it’s quite an intuitive software program that runs on all Windows OS versions, including Windows Server OS editions.
Note: learn more about RAID controller!DiskInternals RAID Recovery
- Supports free data backups
- Works even when the controller is damaged
- Recovers data lost from various scenarios
- Easy to use (Built-in wizard)
DiskInternals RAID Recovery can help to repair damaged RAID drives and recover files from them with high precision. The most intriguing part of using this software tool is the fact that you don’t have to pay for its premium version until you confirm you’ve recovered your lost files. As for data backups, DiskInternals RAID Recovery lets you create multiple free backups at any time you wish.
RAID storage practitioners can leverage DiskInternals RAID Recovery to recover lost data from their RAID arrays, as well as utilize it as a backup solution for their needs. This software works for both hardware and software RAIDs. More interestingly, this software program supports all RAID levels, including RAID 0, RAID 1, 0+1, 1+0, 1E, RAID 4, JBOD, and others.
How To Backup Your RAID Data Using DiskInternals RAID Recovery?
- Download and install the software on your computer system, then launch it and connect/mount your RAID drives.
- Right-click on the drives and select “Create Disk Image”
- Choose a folder to save the image files and that’s all.
You can create disk images at random times to ensure that none of your newly saved data is lost.
Conclusion
Summarily, RAID 1 and RAID 2 are good to try out, but RAID 2 is no longer recommendable as it is hectic and less beneficial compared with RAID 1. However, regardless of whichever RAID level you choose, ensure to make backups at regular intervals to have a “safe” copy of your data in case of disk failures or RAID controller issues. DiskInternals RAID Recovery can come in handy to help you in case of backing up your RAID data or recovering data from a RAID drive.
FAQ
What is the biggest disadvantage of RAID 1?
RAID 1 offers only 50% of its total storage for actual data use because the data is mirrored. Moreover, it might not support hot-swapping of a defective drive, requiring a system shutdown before drive replacement.
What is RAID 1 good for?
Disk mirroring, commonly referred to as RAID 1, involves duplicating data across two or more disks. It's an ideal option for applications demanding high performance and reliability, including transaction-based systems, email, and operating systems.
Why is RAID 2 not used?
The requirement for extended Hamming code generation could potentially hinder system performance. The operational intricacies of RAID 2 can be challenging to grasp. The use of Hamming code and unique disk controllers further diminishes RAID 2's popularity.