I've been following the strategy of using a separate hard drive to make a nightly copy of my laptop's internal hard drive—thank you, SuperDuper!—and also using Jungle Disk to remotely back up all my critical files. In addition, I use Mac OS X's built-in Time Machine to back up to a Drobo. The system has worked well and I've been able to recover several files that I've accidently over-written, even when traveling. And, I was even able to recover from a catastrophic SSD failure with very little hassle, so the system has proven to be pretty robust.
The Drobo Dashboard software recently informed me of an available firmware upgrade for my Drobo, so I installed it without thinking too much about it. Everything seemed fine for the next couple of weeks, but then Time Machine gave me an error message stating that it had not been able to back up in two weeks. I took a look at the server and discovered that the Drobo was not mounted on the desktop. I was able to mount the Drobo over AFP however, and since I was between trips and didn't have a lot of time at home I didn't mess with it further. I just created a new backup overnight and called it good.
Another two weeks went by, and again Time Machine started complaining that it could not perform backups. This time I was home for a while, so I took the time to dig into the issue. First I called Drobo technical support. Even though my Drobo is way out of warranty the tech support people were able to provide some suggestions for why the Drobo was not mounting on the desktop. They suggested that there was some data corruption and that Disk Utility or DiskWarrior should be able to fix it. Well, Disk Utility could not fix the errors found, and DiskWarrior wasn't even able to see the Drobo.
Next I called Alsoft, the publishers of DiskWarrior. These guys went way above and beyond. We did a screen sharing session using iMessage and they spent over an hour hacking on my Drobo. After doing some raw writes to the partition table they were able to get my Drobo to mount and I could see all of my files again. It turns out that the Mac's Core Storage library thought that the partition was encrypted for some reason. Alsoft technical support said that they had seen this a few times before and they recommended that I upgrade my server to Mavericks, which has a more robust Core Storage library.
So while I was upgrading my server to Mavericks, and copying files off the Drobo onto a separate external hard drive in preparation to reformat it, I did some more web searches. Reading through the Drobo knowledgebase and Apple community forums I discovered that Drobo does not support encrypted Time Machine backups! It was then that I recalled that I had checked the option to encrypt my Time Machine backups when I mounted the Drobo via AFP and created a new backup. So I placed another call to Drobo technical support and confirmed with them that they offer no support at all for encrypted Time Machine backups. According to them, there is absolutely no supported way to encrypt Time Machine backups that are stored on a Drobo, regardless of model.
In light of the spying scandal around the NSA, encrypting all my data has become a higher priority for me. All my computers require a password to start up and all their hard drives are encrypted. However, if my backups are unencrypted that is a glaring hole in my privacy strategy. And, unfortunately, it appears that Drobo is unable to handle any sort of encryption for Time Machine backups.
So now I need to look for a different storage solution that can support encrypted backups from Time Machine. The two most popular options seem to be RAID drives from Promise Technologies and from La Cie. While my Drobo has been using FireWire 800, the transfer rates seem slow. (This may be due to the Western Digital Green hard drives I use, but it seems that many people report slow performance from the second-generation Drobos regardless of the kind of hard drives installed in them.) So if I get a new RAID box I'd like to get one that supports Thunderbolt, since that seems to be the new preferred interface for attaching storage to Macs. Only the Promise boxes seem to support Thunderbolt 2, the 20 Gb Version of Thunderbolt, but frankly since I don't do any near-line video editing of 4K video it probably isn't worth the premium over Thunderbolt 1, the 10 Gb version.
(I should mention the third option, which is to buy a Time Capsule. While this is probably the most hassle-free way to support Time Machine on my home network, the Time Capsule does not provide additional storage space for regular files, and it would duplicate the functionality of the Airport Extreme that I already own.)
So the big questions are: 1) Can the Promise or LaCie RAID drives support encrypted Time Machine backups, and 2) Can they serve a dual purpose: back up Time machine clients, and provide storage for all my media and video? The LaCie 5big seems to allow splitting the array to support both purposes. I would imagine the Promise arrays do, too, but I don't know for sure.
So that's where my home backup strategy stands today. I can't say I'm real happy that Drobo does not support encrypted Time Machine backups, so I'm looking for alternatives to help keep my data private and secure.