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0 pointsgordonhart8mo ago0 comments

Backblaze reports an annual failure rate of 1.36% [0]. Since their cluster uses 2,400 drives, they would likely see ~32 failures a year (extra ~$4,000 annual capex, almost negligible).

[0] https://www.backblaze.com/cloud-storage/resources/hard-drive...

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4 comments · 1 top-level

joering28mo ago· 3 in thread

Their rate will probably be higher since they are utilizing used drives. From the spec:

2,400 drives. Mostly 12TB used enterprise drives (3/4 SATA, 1/4 SAS). The JBOD DS4246s work for either.

antisthenes8mo ago

Not necessarily, since disk failures are typically U-shaped.

Buying used drives eliminates the high rate of early failure (but does get you a bit closer to the 2nd part of the U-curve).

Typically most drives would become more obsolete before hitting the high failure rate of the right side of the U-curve from longevity (7+ years)

toast08mo ago

I bet you still have a higher early failure rate because of the stress from transportation, even if there's no funny business. And I expect some funny business because used enterprise drives often come with wiped SMART data, some drives may have been retired by sophisticated clients who decided they were near failure.

dist-epoch8mo ago

Physically moving the drive tends to reset the U-shape. Some will be damaged.

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