One of my clients has an IOmega ix12 - a rack mounted, 12x3.5" bay NAS. This one in question is running 2.6.5.something firmware and has (or should I say had) 8 x 1TB disks in it. Today it dropped another one. The NAS has been set up with a RAID10 with total storage of 2TB (1.5 or so in reality). Although it has this redundancy, I can assure you it's not all that it's cracked up to be. In the main storage pool is a number of iSCSI drives shared out with various ESX servers. Sadly, the largest and most important of these iSCSI drives has an unfortunate tendency to vanish whenever there is a disk issue.
Today one of the drives failed. No big deal right? RAID10 is tolerant of such faults usually. This one kept going except for the aforementioned large drive that disappeared like magic. After replacing the disk, impatiently waiting for it to rebuild and then attempting to reconnect the iSCSI drives I realised I still couldn't see it. The fix? Turn the NAS completely off, count to 30 and turn it back on again. Once it booted, just like magic everything reappeared. Be wary of this. My previous post was the precursor to this. Finding out the actual issue is still to be completed.
I'm concerned about upgrading the firmware because the backups, while reliable, are never straightforward to recover and I'd hate to have to recover so many disks. Its a job for next week I reckon.