"Jon Green" wrote in message
...
On 25/06/2010 17:28, Clive George wrote:
On 25/06/2010 17:03, Jon Green wrote:

I suspect that Mike meant more than just the drives. If you're dealing
with mission-critical data, it's imperative to keep a hot spare RAID box
too, in secure storage away from the building, so that you can bring up
the data set ASAP after a RAID main board failure. There's absolutely no
guarantee that the drive set will work together in a different model or
make -- in fact, it's pretty-much certain they won't.

Once you're doing that you may as well have the second RAID (or rather
filer) mirrored from the first, and have a truly hot DR system.

That'll work...so long as the backup RAID isn't totalled by the same fire
or power surge that nargled the primary!

Or the more likely software fault.


It won't absolve you from having the hot (well, warm, since it's not
connected or running) spare and the backups off-site for full disaster
recovery.

So now you've got three sets of kit! Primary, local mirror, off-site hot
spare.)

Four, the off-site kit should be a replicate of the main site so you can use
it to provide the same service.

We had fully functioning SystemX exchanges inside containers so we could
park one outside and exchange, connect up the trunks, etc. and away you go.