3DR -- a new way of thinking about data recovery

Computerworld - Q: I recently heard you speak about 3DR as a new way to think about backup and recovery, can you elaborate? -- J.M., Kansas City, Mo.

A: You did hear correct, and I'm woefully behind on the paper that lays it all out, but let me give you the top line points.

3DR is a way of thinking about data recovery -- at multiple levels, from local through true disaster. It is a construct for putting your brain to work around what data should have what protection levels and for how long.

3DR stands for data recovery, disaster recovery and doomsday recovery. The first two imply that recoveries, for any reason, occur from disk. The last one from tape. We want you to never have to use the last level.

In order to grasp the concept you should first try to forget everything you know and assume about backup and recovery -- specifically, the way you do backup and recovery today.

Assumptions:

1. All recoveries happen from disk, as close to the application as physically possible.
2. All remote recoveries, required due to major outage at the primary facility(s), occur from disk.
3. Tape is used to create a certain confined number of deep archived backup copies of unique data sets and is hopefully never, ever needed.

So in the first stage -- the data recovery stage -- we back up to a disk-based system. We want everything backed up to that system, and we want to keep stuff there forever if possible. It may be a simple array that becomes the target of our existing backup/recovery software, such as a block-based RAID array or a NAS system. It may be a VTL (virtual tape library), which is a disk box that emulates a tape device(s) to the backup software. Here you are limited only by size and money perhaps. That's why technologies like data de-duplication are so huge here -- if you only truly write unique blocks and/or files, you'll see 20:1 or greater "compression" capabilities. That means you can legitimately keep pretty much all the data ever created in one nice "recovery pool," forever. Any time you need to perform a recovery it is done from this disk pool, online, really quickly. Other features like CDP (continuous data protection) are also good here -- and everywhere else -- so that you can add increased granularity to the recoverable data.

The second stage, disaster recovery, simply implies that an exact replica of the first stage is remotely shipped off-site to another location. Again, having technology like data de-duplication makes this more than feasible and more than reasonable from an expense perspective. I can have all of my primary sites replicate their Data Recovery staged data to a single, or multiple, disaster sites so that now I can recover off of disk even if I lose a facility. Seems straight forward enough.