Re: RAID Reliability Calculations

chris_at_thedunscombes.f2s.com wrote:

> 10 TB of data, 72 GB drives with 1,400,000 hrs MTTF

First, thanks for doing this, I think such exercises are useful and informative.

But just a small MTTF rant:

I think the manufacturers' MTTF figures are statistically abused. I think they throw out some failures that happen, and have unrealistic physical testing environments compared to the real world.

By the calculations, I should maybe have seen one multiple disk failure in my career, yet I sometimes see several per year.

If anyone can shed some light on these notions, feel free.

Joel Garry
http://www.garry.to

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