Best Network storage solution?

Hmm. Food for thought. Maybe strategic delay is in order.

We already have periodic backups, but they don’t solve the problem of losing email or whatnot in the interim. We know about putting DVDs in an offsite location for fire, etc. We don’t use tape, though. We had a tape drive circa 1999, and it was so loud and so slow that we abandoned it. Have they improved radically (other than capacity)?

Math check: if p is the probability of failure, it would seem the probability of no failure in n drives would be (1-p)^n – which should be less than 1-np. Right? Not much less for small values of p, though.

That math is like saying “Well, multi-drive simultaneous failures are not much of a problem, so let’s exclude that from our calculations”

Murphey’s Theory of Drive Failure is the applicable math: If a RAID array has not been backed up recently, two drives in the array shall fail, causing the array to break.

It helps to map out the usage or failure scenarios you need this for and then work from there. For example, when I set up my backup system last summer:

  • Hard drive failure
  • Entire computer fails
  • Computer destroyed
  • Apartment destroyed
  • Anything beyond this will kill me, so it’s irrelevant.

Ended up going with Acronis True Image Server on every machine doing nightly backups to an extra hard drive in my server and monthly copies of the newest backups to the off-site hard drive in my car.

If you want to stay in the realm of math, the problem with this reasoning is that it assumes that the probability of failure of each drive is independent. Since they are sitting in the same place, in the same computer, with possibly the same design, that assumption does not hold. Things like fires and, I don’t know, flukey power supplies mean that certain failures can kill all your drives at once.

D-Link’s DNS-323 looks interesting. Probably should wait for reviews, though.

Inching toward the NAS of our dreams

I’ve heard tremendous goodness about Buffalotech’s terraservers.