[joshcafe]

My favorite trick for this lately has been to use a stripe of mirrored pairs, where each pair is a WD Gold and a WD Red Pro (of matching size).

They're very similar drives (AFAICT, WD Gold is just a Red Pro but with a higher lifetime r/w rating) but it makes me feel a bit better that they're not from too similar of batches without having to actually temporally space out my purchases. I can buy 1 of each in the same cart.

And then for truly unrecoverable data, I back it up to S3 Deep Archive which seems to be one of AWS's only reasonably priced offerings. Don't ask me how much it's cost in egress bandwidth to pull it all back though. I'm hoping if I end up needing it I'll be grateful enough for my foresight to justify paying it.

[lowbloodsugar]

So they can fail at the same time or did you make sure they are from different batches? Anyway, why use four disks from the same manufacturer???

[joshcafe]

I'm not sure what exactly you mean - they're different lines of drives. And different SKUs on Amazon. The probability of me getting sibling drives out of that - and that's assuming the only difference between red pros and golds are binning - is infinitesimally small.

[em-bee]

in my case i use 2.5" 5TB disks. there is only one model from one manufacturer making those. i bought one each from two different shops located in different parts of the country 5 years ago. i used them in a mirror raid. one of them died a year ago. then i got two more drives, one of which was second hand slightly used. the price was good and i figured it was a good way to ensure i'd get drives from two very different batches.