By Jason Snell

January 21, 2021 4:19 PM PT

Raiders of the dead drive

Back in the early days of the pandemic, the Drobo 5D disk array attached to my Mac mini died—and with it went my access to all my archival podcast and video files (including a few works in progress), a backup of my photo library, and a large collection of movies and TV shows ripped from DVDs and Blu-Rays.

Over the course of the next few weeks, I spent a lot of time pondering what my backup strategy should be and what I should get to replace my dead Drobo as my household’s mass storage device. I detailed a version of this story on Upgrade back in May, but never wrote about it. So here’s the story of where I started and where I (happily!) ended up.

RIP, old buddy

I have been using Mac minis as home servers for years, and my most recent one is an upgraded model from 2018. Since I find it super convenient to have a Mac available on my network at all times, I haven’t ever been in the market for network-attached storage devices. The Drobo 5D was a five-disk array attached to my Mac mini via Thunderbolt, with five spinning disks storing about 12 terabytes of data, with data distributed across the drives so that any one of them could die and be swapped out for a new one without losing any data. (And in fact, this had happened—over the course of many years I’d swapped out all but one of the original drives I had installed in the Drobo, and had never lost any data.)0

But guarding against the loss of an individual hard drive isn’t the same as guarding against the loss of the Drobo hardware itself. And that’s what failed in March, the Drobo 5D hardware. Drobo Support had me run a few diagnostics to confirm that while the data on my drives (in Drobo’s proprietary format) was probably secure, the unit itself was not.

In order to close the book on the Drobo side of the story, I’ll reveal that the data was intact on the drives, and I was able to buy a used Drobo 5D on eBay, install my drives, attach it to my Mac, and copy off all the data. (And then I sold that Drobo on eBay for more than I paid for it!) But the incident had reinforced something I had been feeling for a few years—that I didn’t want to stay in Drobo’s proprietary world. But I did appreciate having a multi-disk array with lots of storage and redundant protection against drive failures.

The backups held, mostly

It took quite a while to confirm that the drives in my Drobo were still functional, and the data on them would be retrievable. In the interim, I proceeded under the assumption that I wouldn’t get access to that data, and turned to my backups.

I use Backblaze for online backup, and I was happy to discover that my backup set was safe on Backblaze’s servers. However, I didn’t back up everything to Backblaze—the contents of my video library and my Windows virtual machines weren’t in there. Still, it would get me my most important files—and Backblaze offers a service where it will send you a USB hard drive containing your backup. Despite the creeping pandemic, a week later I had a USB drive containing all my data.

I was also using the ARQ Backup utility to use some of my extra Dropbox space to back up some of my files more regularly. This provided me access to my most vital in-progress work, including some files that hadn’t yet had a chance to back up completely to Backblaze.

Unfortunately, I also discovered a hole in my backup strategy: The evening before the Drobo died, I had moved a podcast project from my iMac to the Drobo. My iMac’s Time Machine backup didn’t catch it, and neither Backblaze or ARQ were able to run before the Drobo died. That data was lost unless the Drobo could be retrieved, though I was able to piece together most of the files from other sources with only some lost work.

The lesson here: Offsite backups are vital, and they work. One is nice, and two is even better. I was very happy with Backblaze’s USB backup service—they charge you for the drive, but if you return it within a relatively generous window, they refund that charge—and using ARQ to provide a second set of backups in some of my unused cloud storage also proved helpful.

Hi, we’re the replacements

So, with the Backblaze USB drive and (eventually) the eBay Drobo, I got all my data back. But where to put it? I decided to buy an OWC ThunderBay 4 RAID, and ordered two 12TB hard drives to go with two lightly used 8TB drives from the Drobo in the four-disk enclosure.

The Thunderbay hardware comes with a feature-limited version of SoftRAID, an app that allowed me to configure my storage to resemble the setup I had on the Drobo. Unlike Drobo, SoftRAID doesn’t let you mix and match drives of different sizes, so I set up 8TB on all four drives to be a RAID 5 volume with a total of 24TB of available storage. As with my Drobo, RAID 5 means that if one drive were to die, I could swap it out and replace it with a new drive without losing any data.

SoftRAID also allowed me to set up the spare 4TB portions of my two larger drives as a mirrored volume, which I use for Time Machine backups from my other Macs. Because that volume is mirrored—in other words, all the data is identical on the two separate drives—I’ve once again got some data redundancy in case one drive mechanism dies.

My Drobo 5D also included a 256GB SSD that it used as a cache; I bought a tiny enclosure to turn that into a USB hard drive. That drive is now set up to be a bootable backup to my Mac mini’s internal drive, just in case something bad happens there. Use all parts of the buffalo, I say.

Two is one and one is none

Finally, I decided to bite the bullet and finally commit to having a local backup of my enormous storage drive, something that I wasn’t willing to do before—and which almost bit me. I took the two largest drives from my old Drobo setup and installed them into a cheap older-model OWC Mercury Elite Pro Dual two-disk enclosure, and formatted those drives as a single volume. Every few weeks I plug it in, turn it on, and run SuperDuper! to make a backup.

The good news is, I didn’t lose any data. I had to buy some new hardware, though at least I made $100 on selling the Drobo I bought on eBay! And I gained a new perspective on what I’m truly willing to lose from my big server hard drive. I was more than happy to pay a few hundred dollars for the privilege of not needing to rebuild my video library. And I reconfigured my backup strategy to make it less likely that a failure at just the right time would wipe out an irreplaceable set of files.

So here’s my advice to you: Make sure your stuff is backed up to the cloud. Consider a local backup, even if it’s for an enormous server that’s supposedly redundant. And thus far, my experience with the OWC Thunderbay and SoftRAID has been great—but I won’t know for sure just how I feel about it until a drive fails and I’ve got to go through process of replacing it.

I look forward to the day when I can replace spinning disks with small and silent SSDs for large-scale storage, but I’m not there yet. I hope my new setup will last me until the day when it’s possible.