If Backblaze s 61,523 operational hard drives are any indication, not often.
On average, Backblaze reports its drives have a fail rate of 1.84 percent in Q1 2016.
Its most used drive was a 4TB Seagate, while the 2 and 3TB HGST have a slightly better lifespan.
HGST was far and away the best drive on Backblaze s test; it routinely hovers around one percent failure rate.
Backblaze obviously isn t the only horse in the race when considering servers, but it s a good look at best practices for those interested in building their own server.
If your app or service depend on it, looks like HGST may be the way to go.