For a few months, the two gadgets of my desire has been the Drobo and the Fujitsu Scansnap. This article is about my recent experience with the Drobo. The Drobo is a wonderful thing that you can hook to your computer, throw any old Serial ATA hard drives into, and back up Terabytes worth of data (up to 16TB) easily and without worries. They have touted this thing on TWIT and Macbreak Weekly and I’m sure in many many other places. It is the wonder box, because it stripes the hard drives so that your data is backed up in a what they call a “BeyondRAID” configuration and even if a hard drive dies or you pull one of the hard drives out and put another one in, you won’t lose anything.
It’s also super simple because you can just look at the lights on the front to see how the drives are doing and the blue lights on the bottom show how much storage you have left. What could be simpler?
Having never seen one of these in person, I was interested when I saw one of my clients had gotten two and had them working away.
The first thing I noticed was that one of the Drobos was not mounting on the iMac to which it was connected. The Drobo comes with some software that runs on the Mac and gives you information about what is going on with the device. This “Drobo Dashboard” was saying that the disk was “unlabeled.” It used to have a name, but now it had none. In the Dashboard there is a pie chart that shows how much space is used and how much is available. I could see there was 750 Gigabytes worth of data on this thing, that was now unreachable. I checked the disk utility and the Drobo was showing up but you couldn’t verify the disk, repair disk permissions or repair the disk.
What I found was that this particular Drobo had a habit of spontaneously disconnecting from the iMac. Why? Well after a little investigation I found that the firewire 800 cable had a broken interface. The little square in the plug that went to the Drobo was broken. This must have caused it to dismount on its own repeatedly without being ejected. The warning that comes up when you unplug a drive from a Mac, might have some truth to it. For the same reason we don’t make a habit of shutting our computers down with the power button, we don’t disconnect drives without ejecting them. What can happen, especially, apparently, with the Drobo, is that after a while the drive structure can become corrupted and all of a sudden the computer doesn’t know what is on the drive anymore. The data is there, but the file structure is not.
I called Drobo support and talked with a very nice woman, who walked me through the process of updating the dashboard software and the Drobo firmware. In the end the disk was still unlabeled and she suggested that I try a third-party software like Disk Warrior, Data Rescue II or Techtool. I took the firewire off and replaced it with USB and ran Disk Warrior on the Drobo and after it went through and found the directory structure was damaged, it mounted the drive on the desktop and recommended that I just try to recover the data. It said it couldn’t replace the directory structure.
I then decided to copy the data to another drive and let it run overnight. The copy message said it would take 33 hours. The copying stopped on its own long before the data was copied over. I came in the next morning and decided I was going to try a command line utility that was suggested to me to repair the file structure. Before doing that I decided to just plug the Drobo in with a different firewire cable and reboot the computer. The Drobo mounted and seems to be fine.
What probably happened: The Drobo had a bad firewire cable that caused it to unmount unexpectedly. Eventually the file structure became corrupted. Either Disk Warrior or the Apple operating system rebuilt it.
So here’s what I learned from this experience.
1. Make sure your firewire 800 cable doesn’t have a broken little square in the end. This will cause disconnections that can corrupt file structure and leave your Drobo “unlabeled.”
2. Drobos aren’t infallible. I think they are mainly just a great place to back stuff up.
3. With these larger hard drive spaces, moving data is going to become more an more difficult. It takes a long time to move 750 GBs of data. If there is any error along the way it just stops. Applications such as Chronosync, make this much easier to synchronize and copy data. Once the Drobo was up and running I copied the data to another drive using Chronosync.