Been using my second gen 4 bay drobo (firewire 800, usb, 3 3tb disks and 1 1.5tb disk) for years as the main drive for a mac mini media server.
About a month ago it said one of the drives was failing and went into rebuilding mode. After a couple of days the drive unmounted, and all the lights went solid orange. After looking around the forums I tried several variations on ways to get it back up:
- rebooted computer and drobo
- turned drobo off, removed drives, turned drobo on until it came up in the dashboard, then off, reinstalled drives and rebooted
The first several of times the reboots happened the drive would appear and be usable during the rebuild. To speed things up, I shut off the computer. Eventually these all ended with solid orange lights.
The next couple attempts started the same way, the drive was never mounted on the computer, but was visible to the dashboard. These ended with the familar solid orange lights.
Finally, I bought another identical drobo, made sure it had the current firmware and swapped discks. Same result. Starts to rebuild and within a day, it ends with solid orange lights.