I have a Drobo 2, connected by Firewire to Mac OS X 10.7.4 It has four 3TB drives in it. Last week, shortly after I applied the latest Drobo update, the Drobo indicated that one of the drives was defective. I pulled that drive and replaced it on Tuesday. The rebuilding process began, and has been running for the last week. Today, the Drobo has started cutting out repeatedly: it runs for a while (ca. 1/2 hour), showing the rebuilding lights; it then cuts out, reboots itself, briefly shows a solid red for the top drive and gives the warning of not enough disk space, and then switches over to flashing yellow and gives the warning for rebuilding. I’ve been trying to get my data off, but there’s a lot of data (5TB) and the constant cut-outs make it difficult to move more than a small handful of files at a time.
I tried running disk utility to repair the disk, but this has not helped.