Review: Is Your Data Worth a RAID from Western Digital?

Photo: Evan Ackerman

Hearing someone tell you that you should backup your data is, in the words of one IEEE Spectrum editor, "about as impactful as your dentist telling you to floss." It's not fun, it's not exciting, and the short term consequences are usually nonexistent, so we often don't do it. You know what, though? Teeth are replaceable. Your data aren't. Back your stuff up. And if you're looking for a place to start, Western Digital has some ideas, just announced today.

Western Digital is announcing four new NAS (Network Attached Storage) systems today: two are designed for prosumer "experts" (you've got a lot of data that you take seriously), and two are designed for small businesses (you have a bunch of users inside and outside your network and need to run apps and stuff). A NAS is a box that has a hard drive inside it that lives on your network (you plug it into your router with an ethernet cable), although you can also access it via USB. It can talk to any computer on your network, wired or not.

These have been around for a while, and are boring, because lots of them exist.

WD's new NAS drives are a bit different because instead of just having one hard drive inside of them, they have two or more drives in a Redundant Array of Independent Disks (RAID) configuration. RAIDs offer several advantages over your standard lonely hard drive: they can either be a much faster place to store your data, a much safer place to store your data, or both.

Here's the deal with RAIDs: they come in different levels (0, 1, 5, and a bunch of other less common ones) that refer to the way in which the multiple drives work together to manage your data.

RAID 0: Usually used with two drives, data are divided up and written to all the drives at the same time. Makes for really fast performance, since you're writing to (or reading from) multiple drives all at once. However, since the data are split into pieces, having one drive die on you means that you can't read anything off of any of the other drives.

RAID 1: Usually used with two drives, data are duplicated onto each drive. If one drive fails, your data are completely safe. Downside is that you're only able to use 50% of your total drive space because of the 1:1 duplication.

RAID 5: Used with three or more drives. Offers the best of both worlds: fast reading and writing, with your data protected from the failure of a single drive, and you can utilize ⅔ of the total drive space or better.

In the past, RAIDs have been relatively complicated and expensive to set up, and they haven't really been a solution designed for consumers. Western Digital has been offering a desktop RAID 1 for a while (the MyBook Mirror), and for what it's worth, I've bought three of them over the years, because I've spent enough time around hard drives that I expect them to fail eventually, and when they do, I want to be prepared.

90% of hard drives will operate for at least three years before failing. After three years, you're looking at a 12% chance per year of failure. But even in those first three years, a 10% chance of potentially losing all of your data is (at least to me) a risk that I don't want to take. And that's why I rely on RAID systems that are resilient to drive failures.

Now, you may already be backing up your data (and the rest of your computer) using a simple external hard drive. And that's great, because you're effectively running a RAID 1 (mirrored) array. Personally, I like keeping all of my important data (and there's lots of it) on its own external drive, because I find it easier to access on different computers, easier to organize, and easier to expand when I need to. If you already have a backup solution that you like, that's great, you can stop reading six paragraphs ago. But if you need something new, or want something better, WD's new generation of consumer and prosumer drives will keep your data protected against drive failure, and do a whole bunch of other stuff at the same time. 


Let's take a look at what Western Digital is announcing. They've got four new NAS RAID systems, two of which are prosumer and two of which are for small businesses. We're going to focus on the prosumer ones, because they seem to be able to do almost all of the stuff you're likely to care about, and they're cheaper.


The NAS itself is pretty straightforward: there are two different systems, one of which can handle two drives, and one that can handle four (although you can use it with fewer). The primary interface is ethernet, although you can also plug them directly into your computer with USB 3.0, which is comforting. The other difference between the two bay and the four bay is that the four bay gives you a little screen to let you know how it's feeling, and there's an additional USB 3.0 port on the front that we'll talk about in a bit.

Setup is essentially nonexistent. You plug the drive into your router, into an outlet, and turn it on. Once it's running, the browser-based configuration takes maybe 3 clicks and 15 seconds, and you're done, with network access to your drive. Totally anticlimactic, just the way it's supposed to work (but rarely does). 


Once the drive is purring along (it's got a big fan in the back that has so far only run for me on startup; otherwise the thing nearly silent), all interactions are through your browser. You can set up accounts for different users and give them access to different folders, monitor the health of your disks, set up automatic backups, and enable media streaming. The interface is lovely to look at, and easy to navigate and use.

There are a few other features that are worth highlighting: one is remote access, which is a way of creating your own (for lack of a better term, I'm sorry, I tried) "personal cloud." Using a web service or an app, you can enable full access to anything on the drive from anywhere you have Internet connectivity. It's the same sort of thing as any other personal cloud service, except free and you retain control of all of your stuff. This also makes it easy to share files with other people: You can give them cloud access to your files and let them download them from you directly.

Western Digital is trying to get people to make apps for these drives, and they have a few on launch. Nothing super interesting yet, except for Dropbox, which lets you sync your Dropbox with the drive (it syncs both ways). Additionally, you can back up the drive to other clouds, including Amazon S3 and Elephantdrive, if you want additional offsite backups.


The other feature that I like is the USB 3.0 port on the front of the drive. It's designed to interface with cameras and portable USB drives, and there's a configurable button above it. You can set it up such that when you plug in, say, a camera, the drive will pull all of the pictures off of that camera, put them in the folder that you've preset, and then wipe the camera clean. It can work in reverse, too, in case you frequently need to move a large amount of data around on portable drives.


Alright, down to business. If you want one of these drives, they're available now, and the pricing is all based on capacity: for the two-bay EX2100 and operating system (add your own drives), you're looking at $250. With 4TB of total capacity, you're up to $430, and the EX2100 tops out at $750 for 12TB. The beefier four-bay EX4100 starts empty at $400, and you can add drives all the way up to $1450 for 24 (!) TB.

If you like the idea of a NAS RAID system but don't need all of the features of the EX, Western Digital also makes the EX series and MyCloud Mirror, which give you two drives that you can set up in RAID 0 and only cost around $300 for two terabytes of failure-protected space. As far as I know, WD is the only company that offers plug and play mirrored NAS RAID systems like this, and I really like these things.

The cost of hardware like this may seem expensive. And it is expensive; you're buying some big hard drives and a reliable enclosure backed by a lot of software. Put it in perspective, though: if your data were to disappear tomorrow, how much would you pay to have it all replaced? What's the monetary value of years of family photos and videos? How much would you pay after the fact to replace something that's irreplaceable? My guess is that it's a heck of a lot more than a NAS. 

Before we close, it's important to point out that while a RAID is resilient to drive failures, it's not resilient to anything that physically affects the drive itself, like theft, fire, supervolcanoes, or asteroid impacts. For that, you'll either need to duplicate your important data to a cloud service (I do this), or if you're super paranoid like I am, every once in a while make a copy of your important data and put it somewhere far away, like someone else's closet or garage. It's annoying to do this, and it will probably cost a little bit of money, too. But again: what are your data worth to you, and is it more or less than a little bit of money and hassle?

So if you haven't backed up your data in a while, or ever, please, go do it now. Do it with one of Western Digital's RAIDs, if you want. Or do it with something else. It doesn't matter. What does matter is that you find what works for you, and do it, before you're sorry that you didn't.


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