Can we reduce the chance of hard drives failing, and at what cost/ benefit?

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Invest in learning how to better deploy and use monitoring tools. Some tools may cost money. Maybe not all relevent, but here are some buzz-words Oliver has come across:

• Nagios
• NetOps
• S.M.A.R.T.

Data from a company using over 40,000 hard drives

https://www.backblaze.com/hard-drive.html

High-Level Summary

With 40,000 hard drives, Backblaze knows a lot about the reliability of hard drives and shares the statistics: 

• 78% of drives survive more than 4 years.
• The median hard drive survives 6 years.
• Drives have 3 distinct failure modes that follow a bathtub curve:
• Early “Infant Mortality” Failure
• Constant (Random) Failure
• Wear Out Failure
• As long as the temperature is within spec, reliability is not affected by heat.
• HGST drives are generally reliable; Seagate and Western Digital hard drives’ reliability vary by model. (see web page for graphic)