Cloud backup provider Backblaze, which pioneered with its open-source Backblaze Storage Pod, has released data on which, in its experience, is the most reliable hard drive – and which is the least reliable.
While it’s by no means a conclusive case study with data on every major hard drive model on sale, Backblaze’s figures are quite telling. Of the hard drive brands it uses, Seagate, Hitachi, and Western Digital feature most prominently. Seagate has 12 765 drives in use, while Hitachi has 12 956 in Backblaze’s servers. Western Digital has 2 838 drives. There’s also a statistically-insignificant number of drives from Samsung and Toshiba.
It’s worth noting that unlike other enterprises Backblaze uses consumer drives. In the post on its blog, one of the company’s engineers explains that it uses the most affordable consumer-grade drives available, rather than pricier enterprise-level equipment. In cases where a more reliable can be had for not-that-much more money, those are used instead.
Seagate drives, in Backblaze’s operation, are the least reliable. With a combined failure rate of 26.5% after three years in operation. Meanwhile, Hitachi is the most reliable, with only 3.1% of its drives having failed in a three year period. Western Digital comes in at a very respectable second, only 5.2% of its drives having failed after 36 months.
Those numbers don’t tell the whole story, though. Backblaze has charts that track failures over time, and in those it’s clearly visible that both Hitachi and Western Digital have the biggest drop within six months of deployment. After that very few drives fail and there is no sharp drop-off in reliability. Seagate’s chart looks horrendous, with drives failing from the first month all the way to the last.
It’s also noted that certain drives are not included in the data simply because those don’t fit the criteria of what’s needed by Backblaze. Seagate and Western Digital both have low-power drives that use less energy, and those are noted to be unsuited for write-intensive operations. However, Backblaze goes into detail about which exact models of drives are in use – typically high-capacity models. Anybody in the market for a few multi-terabyte drives would do well to at least consider some of this data, since these are consumer drives and it will apply to whatever you’re considering for your storage needs at home.
Regardless of what hard drives are in use, though, users should always have backup measures in place. Having a more reliable drive simply reduces the risk of failure, but doesn’t eliminate it. Use of cloud storage and a separate backup disk will keep your data far safer than any low-failure-rate hard disk ever will.