[magnawave]

I think his point was about drives silently returning corrupt data, not that you shouldn’t have redundancy. Absolutely you should have redundancy and backups.

At the (tens of) thousands of drives scale (and where you treat drives as cattle) having some extra checks and balances for what you write is an excellent idea. Even better is doing that in a distributed way so multiple machines make that same decision. Occasionally you will run into a drive where the firmware has jumped the shark or some such. (Or CPUs or memory or bus issue for that matter).

But generally speaking drives DO know when they are returning bad data and will error before they will do that. The odds are about as good as other forms of hardware errors that will eat your data.