OK, here goes. This is a work in progress, as it has been for the last 18 months.
I presently have a DroboPro with two 2TB drives plus 6 1TB drives, with 3.9TB used (72%) and dual disk redundancy. I have two volumes on that drive, a 16 TB general use, and a 4TB Time Machine.
The general use volume has three DON’T TOUCH archives from Jan 2008, Aug 2008, and Sept 2009, created using File Copy, plus a fourth archive created using ChronoSync. All of these are replicas of my master files on the RAID 0 array in the Mac Pro.
Time Machine backs up everything except the Drobos, and excluding Virtual Machines (which take too much space). I used to use a Time Capsule for that purpose, but the power supply died, and I ended up salvaging the drive from within it. Never again will I buy a backup device without removable drives!
However, if some kind of a failure (hardware, firmware, or OS related) of the DroboPro should occur, I would want a backup of that data.
For that reason, I have a local duplicate of all of the archives (except for Time Machine) on a Drobo V2 with four 2TB drives, connected via FW 800. That is also synchronized with ChronoSync, and it is supposed to be bootable, although I haven’t tried that yet.
I normally don’t keep the Mac Pro up and running, for energy conservation reasons among others, but I would like to get to the point where I could download/synchronize my MacBook and/or my office XP with those files at any time, if need be. I’m not quite there yet, but for that reason I have a CrashPlan+ archive of the current data on another Drobo V2 connected to my Mac Mini.
In addition, that volume contains a current archive of all of the user data on my XP machine at work, synchronized via SyncBackPro.
A third Drobo (V1) has three 1 TB drives, and is generally used for temporary files if I’m moving things around. I might ultimately move that drive to my office, to back up my Mac Book.
Finally, a fourth Drobo with four 1TB drives is formatted with NTFS, and is used to backup my work laptop (XP). At one time, I had that synchronizing nicely with my Mac Mini, using SyncBackPro. However, because the Mac Mini is necessarily exposed to the Internet, I’m not crazy about keeping unencrypted files on it. For that reason, even though I am not at all enthusiastic about using proprietary encryption schemes such as Blowfish when AES is available, CrashPlan+ has some undeniable benefits.
From a usability and overall security perspective, I would almost kill to have SyncBackPro available on the Mac. Although it doesn’t end-to-end encrypt the files, and therefore the files at the storage location are potentially exposed, they probably do the best job of any in terms of being foolproof.
ChronoSync is getting there – certainly the current version is better than version 3. Likewise, CrashPlan+ isn’t necessarily bad, and it supports multiple platforms.
In summary, there are three problems to be dealt with:
- How to replicate the data conveniently to the backup drive, wherever it is
- How to ensure the confidentiality of the data en route and at the final resting place
- How to be absolutely sure of the integrity of the data in both the local and remote locations. That is the biggest challenge of all.