Support
Understanding RAID: A Comprehensive Guide
RAID (Redundant Array of Independent Disks) is an essential technology for professionals and businesses that require data redundancy, speed, or both. Whether you’re a creative professional working with large media files, a business looking to secure critical data, or a home user needing extra protection against drive failure, RAID can offer a solution.
In this guide, we’ll cover the fundamentals of RAID, the differences between software and hardware RAID, the software tools available for Mac users, and why RAID is no substitute for backups. We’ll also highlight some of the RAID-capable devices available at Macfixit Australia.
What is RAID?
RAID (Redundant Array of Independent Disks) is a storage solution that integrates multiple drives into a single logical unit. The goal of RAID is to enhance performance, increase storage capacity, and provide redundancy in case of drive failure.
RAID is used in various settings, from home users backing up important files to enterprises managing massive amounts of data in server environments.
What Are the Uses of RAID?
RAID configurations offer different advantages depending on the setup chosen. Common uses include:
- Data Redundancy & Protection
RAID can protect data by duplicating it across multiple drives, ensuring that if one drive fails, no data is lost.
- Performance Enhancement
Some RAID configurations, such as RAID 0, distribute data across multiple drives, improving read and write speeds. This is particularly useful for video editors, 3D rendering, and high-speed computing.
- Storage Management
RAID allows multiple smaller drives to be combined into a single, larger volume. This is useful when dealing with extensive media libraries or databases.
RAID is No Substitute for Backups!
Many people assume that having RAID means their data is safe—but this is a critical misconception. While RAID protects against drive failures, it does not protect against data loss due to other causes.
All RAID levels (except RAID 0) offer protection from a single drive failure. A RAID 6 system can even survive two simultaneous drive failures. However, RAID does not protect against:
- Power spikes or surges that damage all drives.
- Theft of the entire RAID system.
- Natural disasters such as fire, flood, or earthquakes.
- User error, such as accidental file deletion
For complete data protection, regular backups are essential. Here’s why:
→If all drives fail simultaneously due to a power spike, a backup ensures your data is safe.
→ If your RAID storage is stolen, your offsite backup keeps your files secure.
→ Backups stored in a different location protect against fire, flood, and natural disasters.
→ Backing up multiple generations of data protects against accidental deletions. If you delete an important file and don’t realize it for days or weeks, you can still recover an older version from your backups.
The Best Backup Strategy
For optimal data protection, follow the 3-2-1 backup rule:
• 3 copies of your data (your primary data + two backups).
• 2 different storage types (e.g., an external drive and a cloud backup).
• 1 offsite copy (e.g., a cloud service or a backup at a different location).
A RAID system can complement a backup strategy but should never be relied upon as the only method of data protection.
Levels of RAID
Different RAID levels offer varying benefits in terms of speed, redundancy, and efficiency.
RAID 0 (Striping)
• How it works: Data is split across two or more drives to improve speed.
• Pros: Fast read/write speeds, full use of disk capacity.
• Cons: No redundancy—if one drive fails, all data is lost.
• Best for: Video editing, gaming, high-speed data access.
RAID 1 (Mirroring)
• How it works: Data is duplicated across two drives, providing an identical copy.
• Pros: High redundancy, data protection.
• Cons: Storage efficiency is reduced (you only get half the total capacity).
• Best for: Data protection, business backups.
RAID 5 (Striping with Parity)
• How it works: Data is spread across multiple drives along with parity information, which allows data recovery if one drive fails.
• Pros: Good balance between speed, storage efficiency, and redundancy.
• Cons: Slower write speeds due to parity calculations; requires at least three drives.
• Best for: Business applications, file servers, media storage.
RAID 10 (Striping + Mirroring)
• How it works: Combines RAID 0 and RAID 1, mirroring data while also distributing it across multiple drives.
• Pros: High speed and excellent redundancy.
• Cons: Requires a minimum of four drives, reducing overall capacity.
• Best for: High-performance applications, database servers, mission-critical storage.
How is a RAID controlled?
There are two primary ways a RAID is managed – with a hardware controller or with a software controller. They are quite different, and each has its own advantages and disadvantages.
Hardware RAID
A hardware-based RAID system offers potentially better performance, but it is dependent upon the hardware the system is using. Because all of the RAID functions are self-contained within the RAID controller, there are virtually no resources used from the host computer system. While possibly the most efficient, hardware RAID systems are also the most expensive to implement.
With a hardware RAID, if any part of the system fails (such as the controller, enclosure, or power supply), you can lose all of your data. With cheaper hardware RAID systems, you can also lose data if there’s a power outage.
Software RAID
A software-based RAID system runs entirely at the operating system level, making multiple physical drives show up as a single volume or drive on your desktop. They are also very cost-effective and easy to implement.
With a software RAID, your data can be split across different enclosures for complete redundancy – one drive can completely stop working, and your data will be okay. You can quickly move a drive from a failed enclosure to a new one, and all of your data is preserved.
Soft RAID vs. Hard RAID: Key Differences
| Software RAID | Hardware RAID | |
|---|---|---|
| Performance | Performance is limited by the host CPU. | Performance is limited by the RAID controller hardware. |
| Data security | Relies on software-based encryption mechanisms, if supported. Could be affected by host system vulnerabilities, including viruses. | Often includes hardware-based encryption mechanisms for enhanced data security. Operates independently from OS and is not vulnerable to attacks. |
| Compatibility | Compatible with host OS by default. The compatibility between different operating systems is limited. | Compatibility is limited to a specific list of supported host operating systems. |
| Cost | No upfront costs, as no additional hardware is required | Higher cost due to the purchase of additional RAID controller hardware |
| Reliability | Dependent on the host OS, prone to CPU failures. | More reliable with dedicated hardware and advanced data protection features. |
| Replacement | Even in the event of OS reinstall, the software RAID reassembly is quite straightforward. | Hardware-based replacement is straightforward, however, requires the purchase of a similar RAID controller. |
Software Solutions for Software RAID
1. OWC Softraid
• Advanced RAID levels (RAID 0, 1, 4, 5, 10).
• Drive health monitoring and failure prediction.
• Faster rebuild times compared to macOS’s built-in tools.
2. Apple Disk Utility
• Supports RAID 0 (Striping) and RAID 1 (Mirroring).
• Basic RAID management built into macOS.
Here's our guide on How to build software RAID
RAID-Enabled Devices at Macfixit Australia
Macfixit Australia offers a range of RAID-enabled enclosures designed to enhance data security, speed, and storage flexibility for Mac users. Whether you’re looking for RAID 0 for performance, RAID 1 for redundancy, or more advanced configurations like RAID 5 and RAID 10, we have the perfect solution to suit your needs. Our selection includes high-quality enclosures compatible with Thunderbolt, USB-C, and other modern connections, making them ideal for professionals and enthusiasts alike. Explore our full range of RAID enclosures and take control of your data storage today.
Browse our collection of RAID enclosures here
Final Thoughts
RAID is an excellent way to enhance performance and protect against drive failure, but it is not a replacement for backups. A proper backup strategy is necessary to protect against theft, disasters, and user errors.