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Comment by andy4blaze | Hacker News Reader

The Backblaze Vault design mitigates that as the "raid array" is scattered across 20 different Storage Pods in twenty different racks. You'd need more than three racks to go down before you would be offline. Backup systems in place make that highly unlikely. Andy at Backblaze.

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I'll see from your reports that you're migrating 1000s of 2TB drives to 8TB drives - what is actually happening to your old 2TB drives?

Guess you are not throwing those away so what are you doing with them.

Disclaimer: I work at Backblaze. We securely wipe the drives, then we sell them to a "used hard drive reseller".

I know it's a lot easier to wholesale resell them, but it'd be so awesome if you could dedicate a portion to be sold to the homelabbers among us.

I don't know how that would be more awesome, essentially spending effort towards the upper middle-class hobbyists. I would rather see them sell them directly to the highest bidder and focus the effort on improving their business, or give the drives to charity.

Does "secure wipe" mean ATA SE, i.e. hdparm --security-erase, or --security-erase-enhanced?

For that volume I'd think a degausser would be used.

AFAIK, if you physically destroy the contents of a drive with a strong magnetic field, you also destroy the servo tracks, rendering the drive useless. Modern hard drives can't "low-level format" themselves; they're not mechanically precise enough.

Degaussers render the drive nonfunctional.

They were reusing their 1TB drives to test new pods with. But I think they would only need a hundred or so for that, unless they die faster in that workload.

https://www.backblaze.com/blog/hard-drive-reliability-q4-201...

I guess my question is more about the long term implications of transfer speeds increasing much slower than hard drives space. And if there's a hidden risk to downtime because all of a sudden, a full rack of 32 or even 64TB drive will take day(s) to transfer as opposed to an hour or so because transfer speeds are so slow.

I suppose if you had a single 32TB drive that went offline for say a week, and then once it came back online you'd have some type of pent up demand and a "slow" transfer speed. Storage systems in general spread the load across multiple devices so the effect of slow transfer speed is near zero in most backup and archiving applications and maybe more problematic in transactional applications.

There are implications. ZFS' raid-z2 (which uses 2 disks for redundancy data) was pitched - in 2008 or so - with the idea that disks are now large enough that recovery can take long enough that it's likely that another disk in the raid set breaks before the redundancy is back.

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