How to turn your old hard drives into a RAID array

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Cloud storage is everywhere. Despite the current memory crisis, SSDs have become cheap enough that most new PCs don’t even bother with a spinning disk anymore. And yet, if you build your own computers, chances are you have a drawer of old 500GB and 1TB hard drives that are too small to be useful on their own but still have some life left in them. RAID is what you do with this drawer. Rather than throwing away these hard drives, RAID can give them a new use. Plus, it gives you faster and more reliable storage.

RAID stands for Redundant Array of Independent Disks. The idea here is to combine multiple drives so that they work as a single unit. Instead of storing your files on a single disk, RAID spreads them across two or more disks, resulting in much faster transfer speeds. They don’t match the speeds of an SSD, but they are much faster than a typical hard drive. A RAID array also provides redundancy for your data. Indeed, it is less prone to failures: if one disk fails, you can always recover your files on the other. This is the main reason why RAID is still used today. It’s less about faster speeds and more about convenience and reliability.

A RAID system is not a substitute for a full backup, but it ensures that you won’t lose your data if one of your hard drives completely fails. The idea sounds great, but there are many details you need to know before setting up your own RAID array. For example, there are four different categories of RAID arrays. Each radically changes the results you’ll get from combining your drives. The best known are RAID 0, RAID 1, RAID 5 and RAID 10. Understanding each of them is very important to know exactly what to expect.

RAID 0 essentially combines two or more disks into a single unit without parity. This process, called striping, speeds up file reading and writing times. This can be very useful if you work with large files, like videos or databases, because it combines the total storage space of all drives. But it’s not all good news. The downside is that RAID 0 offers no data protection. If one drive fails, you lose everything. In short, it’s a great way to get faster speeds, but not so effective at protecting your data.

If you need something more reliable, there is RAID 1. With this configuration, the system writes the exact same data to each disk in the array. If one drive fails or disconnects, you’ll still have everything on the other. No need to worry about losing your data: perfect when you’re working on an important project. This doesn’t mean everything is perfect, but the chances of losing your data are much lower. You also get faster speeds, but you sacrifice storage space. RAID 1 uses 50 percent of the total capacity to create this mirror copy. Let’s say you combine two 1TB drives. You will only be able to store up to 1TB of files instead of 2TB.

Then there’s RAID 5 and RAID 10, and this is where things get a little complicated. With RAID 5, data is divided into blocks and written across multiple disks. Its operation requires at least three disks. If one of them fails, you won’t lose your data either. The system uses the remaining readers and algorithms to automatically reconstruct missing data. RAID 10, on the other hand, works much like a combination of RAID 0 and RAID 1. Multiple disks can be grouped into pairs, and each pair will have a copy of its data. Did a single drive fail? No problem. But if a mirrored pair fails, you risk losing your data.

There are different ways to configure a RAID array. They vary not only depending on the operating system you are using, but also the hardware. For example, you can simply connect two or more drives to your computer and create a RAID array using software. This is usually the easiest way, but performance will not be optimal. Apple’s Disk Utility in macOS lets you configure RAID 0 and 1 arrays. It’s similar to disk management in Windows. There are also paid software like StableBit DrivePool and SnapRAID that offer additional features.

But if you really want to take RAID seriously, try using hardware-based methods. They have dedicated controllers that better protect drives from failure and provide better performance. However, they are also more complicated to set up. For example, you may need to purchase a RAID controller to install on your motherboard. If you don’t want to run into all of these issues (or maybe because you own a mini PC), a RAID enclosure might be your best option. They usually come with a built-in RAID chip, so you just plug the drives into it. Just be sure to check the capacities and maximum speeds before purchasing one. It’s the same as choosing USB-C accessories: high speeds aren’t guaranteed for everyone.