This is an update to a previous post. Before you read this, make sure you've read Part One of this story.
After I posted my last, I moved the Drobo over to my Mac mini, so that I could leave it churning as long as it wanted. In the meantime, I received email from Ralph Herbst, the Director of Customer Service at Data Robotics, asking to set up a call for the next day.
Literally 20 minutes before the call, my Drobo volumes reappeared on the mini. I had spent the intervening waking hours reconnecting my Aperture library to an rsync backup of the referenced masters that were on the Drobo. Thanks to my backup regimen, I did not lose a single one of the 20,000 photos that were on the device.
So we had the call. On the line were myself, Ralph Herbst, Tom Loverro (Director of Product Marketing) and Valorie Koch (Technical Support Mgr.). The DR people were very apologetic over the way the technical support incident was handled. In particular, they made it clear that literally everything I had been told by DR tech support was wrong, which tells you a story in itself. My disconnection procedure was 100% correct: unmount the drives, then pull the FireWire cable.
Based on some information that I had (quickly) gathered since the device came back online, we eventually got round to surmising that the problem was a corruption of the HFS+ directory structure on one of the volumes. My Drobo is partitioned into two volumes: 1.5TB for Time Machine and the rest of the virtual 16TB volume for data that I don't keep on my MacBook Pro. Fortunately, the Time Machine volume was the one that was damaged. As I write this, I'm recovering the last of my data from the other partition. That data seems to be OK.
The lingering question, though, is how that volume came to be damaged? I suppose that's something that we'll never know. I can't say that this absolves the Drobo of blame, nor that it conclusively proves that the Drobo itself is somehow defective. It's a known unknown and I guess it will probably stay that way.
I do have one suspicion, though: I've noticed that when your machine goes to sleep for an extended period, the Drobo also goes to sleep. When the computer wakes up, it does so a lot faster than the Drobo and, as a result, Mac OS X throws up the "Device Disconnected" dialog that you see if you pull a USB drive too soon. That's not usually a good thing.
Data Robotics have offered to replace my Drobo unit as a precaution. As I said in my last post, I'll probably continue to use the Drobo in some capacity but those masters are going on a backed-up 1TB eSATA drive from now on.
Let me leave you with this thought for now: music and videos can be replaced with the application of time and/or money. You will never be able to recreate a lost photograph of the day your child was born. Back them up. Twice.