One of the operations that the company has been doing over the past quarter is replacing its 2TB HGST and Western Digital hard drives with new 8TB hard drives from Seagate. The main thrust behind this migration was primarily increasing the data density of its data center and power saving, but on crunching the data Backblaze discovered an added side-benefit -- reliability.
The 8TB Seagate drives have an annualized failure rate of 1.6 percent, which is the same as the 2TB disks from HGST that Backblaze has been relying on for heavy lifting (which now have an average age of 66 months, so the failure is expected to rise due to wear and tear), and considerably better than the 8.2 percent annualized failure rate of the 2TB Western Digital hard drives the company has been using.
This, according to Backblaze, "bodes well for a continued low failure rate going forward."
One of the downsides to moving to higher-capacity storage drives is that rebuilding time following a drive failure is much longer, and this means that there's a potential for more drive failures while the array is being rebuilt.