Is your Drobo up to date? Don't trust Drobo Dashboard for the answer.
Drobo and I have not been getting along this week. I have two Drobo units: a FireWire model and a USB model. I moved them to my office last week, and the USB model started complaining about being low on space. The Drobo Dashboard showed drives in all four bays, and since I hadn't been low on space before, I was confused as to what had happened. About a day later, I checked again (after working hard to delete anything unnecessary) and it showed a missing drive in one of the bays. Not a failed drive, but a missing drive. I shut the Drobo down completely, ejected the drive, and mounted it back on the iMac.
Suddenly I had a lot of free space, but Drobo was acting like I had just put in a new hard drive. It took two days for it to sort itself out.
Everything seemed fine until I was using my iMac a few days later. Suddenly, my iMac said "You have ejected [my FireWire Drobo] without unmounting it." I told it that I had done no such thing, I hadn't ejected anything. I couldn't get the Drobo to remount, even after rebooting. It would work via USB, and it would work via FireWire with my MacBook Pro, but not with the iMac.
I worked with AppleCare to diagnose the problem, and they asked me if my Drobo firmware was up to date. I said it was, and that it was one of the first things I had checked, using the latest version of Drobo Dashboard. My answer was true... except that Drobo Dashboard wasn't telling me about the latest firmware.
I spent all day on Friday talking with AppleCare, running diagnostics, driving back to my house to get my original install CDs, calling AppleCare again, running more tests, and finally having them agree to send a technician out to replace the logic board on my iMac. He arrived this morning (Tuesday) and spent an hour doing the replacement.
About an hour later, the Drobo started acting up again. The install of Snow Leopard was only a week old and I had a completely new logic board, so I was starting to suspect the Drobo. I called Drobo support and their tech asked me if I was running the latest version of the firmware.
"Oh yes," I said with confidence, "I checked in Drobo Dashboard this morning."
"There's a newer version on our website," he replied.
My blood pressure tripled. Sure enough, I have 1.3.5 and, according to Drobo's own release notes, their Drobo Firmware 1.3.6 was released on February 3, 2010. It is posted on their website. It is not a beta. It is released software. They just "aren't pushing it" out to customers.
If I click a "Check for Updates" button in your app, and you have a new, non-beta update on your website, it fills me with a certain degree of rage when your application sits there and lies shamelessly. This is not a debatable point, it's a matter of trust.
I downloaded the latest version of the firmware (1.3.6, as of this writing), opened the .dmg file, and copied the "v.136.tdz" file to my Desktop. Then I held down the control key as I clicked "Check for Updates" in Drobo Dashboard, which brought up a regular "Open" window where I could select the "v.136.tdz" file. I updated the Drobo to firmware version 1.3.6 (Note, usually disclaimers apply: if you decide to upgrade your firmware, be sure to backup your data first, etc.).
And suddenly my Drobo works fine with my iMac.
Of course this prompts the question, "Did I really need to have the logic board replaced on my iMac?" It's entirely possible that I did. Ever since my iMac complained about the FireWire drive being ejected when I didn't eject it, I could not even mount the Drobo. After the new logic board, I could mount it, but Finder would hang and I would have to shut down the iMac and disconnect the Drobo before the iMac would finish rebooting.
On the other hand, that's not really the point. The point is that, when it really mattered, Drobo Dashboard failed to provide me with correct information. The last thing that anyone wants is to doubt what their software tells them.
To their credit, Drobo's phone tech support was able to solve the problem, and did so free of charge for a product that is out of warranty. However, chances are I wouldn't have had to call at all if they hadn't decided to not tell users about an update, even when those users specifically checked for it.