Is there some sort of "key" that only allows the drives to be used in one Drobo? Or can you buy another one if it goes belly-up, stuff your drives into it and get the data back?
Probably. You know any local place to buy a Drobo on a Saturday night when it croaks?
Huh??? Only for geeks and decent-sized businesses. And while I'm a geek, I'm just now filling up my 500GB laptop drive. (Well, I guess I do have a 1TB external sitting around here somewhere... But it's only 1/2 full, maybe.) Hell, a measly time capsule can go to 2TB. An entry-level Drobo with four 2TB drives gives you 5.5TB of storage, which is really quite a lot.
What actually annoys me the most about the Drobo is the cost. In the above scenario, even maxed out, the Drobo costs more than the drives to fill it up. If it was half the price I'd already have one.
Yes, you missed the point... it's a great solution for a growing/resizeable "big drive", but it's not a good place to put your backups. Backups for something that big requires another something that big. And super-proper backups require taking that second "thing" off-site.
And yes, they're overpriced.
For the flexibility, something like FreeNAS in your own hardware is probably smarter, but it won't resize as easily when you add bigger drives later, and it requires a bit more work.
Lots of websites talk about using ZFS stores as a "Drobo-like" system for resizing on the fly, but I've heard some data loss stories from a Tier 4 Sun Engineer about ZFS that would curdle the blood of those using it commercially...
You lose data in a Drobo, you don't pop the drives into something and recover the data. You lose data in ZFS, same thing. Resizeable RAID on the fly is problematic and only the really large/expensive commercial SAN systems really do it right. Not something consumer-priced though. And most of those also use proprietary formats.
There's not a really great solution for "can be read by any computer, is huge, and is cheap" right now for the home market. I believe there are some two or four disk home NAS devices that can be flashed/hacked to run Linux natively and then software RAIDed, which in a pinch those disks could be stuffed in any Linux box and read from, if you knew what you were doing. But that's not very user-friendly.
So stuff like the Drobo is about as good as it gets right now. But you just have to be aware that the thing can go belly up and leave all the data on it unreadable or just plain gone... and most people aren't buying two for redundancy.
There's quite a number of horror stories even right on Drobo's website where they reply politely in their forums and say, "Here's some 3rd party raw disk tools... good luck finding your data."
Been tinkering with the Amazon Cloud computing and storage lately -- they did have a fairly big publicized outage recently -- but in general, that might be an interesting way to go, big disks here at home, and anything important could go not only to their cloud storage but if one were ultra-paranoid, one could set up a cloud-based Linux server to rdiff-backup or similar into using an encrypted filesystem... still thinking about it.
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