Resolving a Drobo Failure

I have a Drobo 5D (drobo.com, amazon.com). When my server started running out of space, I looked around at NAS (network-attached storage) and DAS (direct-attached storage) options, and eventually settled on the Drobo 5D. I wanted something that would be pretty fast, and while NAS units can be fairly fast, they're limited by the network. The Drobo 5D supported thunderbolt, and has a very simple, easy to understand expansion model.

With many RAID units, you need to fill up all the slots right away with drives of the same capacity, and if you want to expand the unit, you need to replace all of the drives with larger ones of the same capacity.

With a Drobo, you can start with a few drives, then when you start running out of space, add a couple more, and if you start running out again, replace some of them with larger drives, and so on. There's a lot of flexibility, which means a smoother upgrade path, which appeals to me.

Other Options

Drobo units, despite being DAS, have a reputation for being fairly slow. The 5D is better than many past Drobos, but it's still regarded as being slower than one might expect.

In the meantime, I have discovered that Synology NAS units, which I've heard great things about, added Synology Hybrid RAID back in 2010, which has many of the expansion characteristics of Drobos. If I'd learned that earlier, I might simply have purchased a Synology NAS. Even now, I'm tempted to add a NAS to my collection.

Problems

Earlier this summer, we had a series of power failures over a period of a week or two. Our power is typically pretty reliable, but we had a brief period of flaky power, I guess.

At the end of that period, when I brought the Drobo back up, it showed up as degraded and didn't mount. Since fault tolerance and recovery is one of the primary reasons to have a multi-drive RAID unit, I assumed the Drobo would recover. I waited a day or two, checking periodically, and nothing changed, so I started reading Troubleshooting material.

Something that came up regularly was updating the Drobo dashboard and the Drobo firmware. I did both. At that point the Drobo went from doing nothing to rebooting every few minutes, which was clearly not an improvement, so I contacted Drobo.

Of course, one of the first questions that Drobo asked me was the obvious -- do you have backups? And, like any technology guy, I know what the right answer to that question is. Yes, of coure, of course I have backups of any important data that I'm storing on your system. But I didn't. It was on my list to get to, but I hadn't done it yet: - Because the Drobo is 8TB how I have it configured currently, and I don't have 8TB of easy storage lying around. I could buy another Drobo to back up to, but they're not exactly cheap. - Because online backup of several TB is not so much expensive as it is painful on bandwidth -- particularly if your upload speeds aren't symmetrical.

Drobo Support

Drobo Support was pretty good, all in all. They were fairly responsive (queries usually got answered the same day or the next), patient and thorough. When all is said and done, I got my Drobo back in working order and my files seem to be basically fine.

Getting there, however, was painful. It took nearly two months. I had issues with the Drobo software, and had to try Thunderbolt, USB2 and USB3. I got logs with the drives pulled out, put the unit into read-only mode, cloned a drive using Data Rescue, replaced it, put the unit back out of read-only mode. I was esclated at least twice to higher levels of support, and sometimes the higher levels seemed less capable and less responsive than the previous levels.

It's not a process I enjoyed.

Still, at the end, I have my Drobo again, I have most if not all of the data that I had on it at the start of the process, and I'm reaosnably happy with the end result, which is what counts, right? Right?

Lessons Learned

So what did I learn?

RAID is not a Backup

I'd heard that lots of times, and I understand that logically an entire RAID unit can fail and if you don't have a backup of the data, you could be in trouble. Still, knowing that a RAID unit is meant to be reliable gives you a false sense of security, and I didn't act quickly enough to get a backup routine going. I'm fixing that.

While RAID units are more robust in the face of failure, they also have more moving parts to fail. Don't rely on your RAID unit, rely on backups.

Drobo Support is Good, but Slow

Drobo was patient, kind, and relatively sane throughout, but it took a long time to get back to a working state. If I'd had good backups, they probably could have skipped many of those steps and get me back to a working state faster, possibly at the risk of needing to do a restore from backups.

Synology NASs look Good

I'm still pretty happy with my Drobo 5D, and I wouldn't suggest that you not get one, but if I were recommending something to someone right now, I might lean towards a Synology NAS instead of a Drobo, and if you really need maximum speed, then perhaps a non-expandable thunderbolt RAID setup, which would be faster than the Drobo.

Of course, there have been some Synology security issues recently, which doesn't fill me with confidnece.