Well, the only thing I trust is my RAIDed ZFS with weekly scrubbing. However, that's not a backup solution. Spinning rust doesn't degrade materially over time when powered off but Flash certainly does.
> Spinning rust doesn't degrade materially over time when powered off but Flash certainly does.
Magnetic media does degrade, moving parts freeze or fail in other ways, and the circuitry can also fail. It’s often possible recover that at some cost but it’s much more expensive than n > 1 copies.
Yes, true, but for a hard disk at _rest_ (in a controlled environment) I posit it's failure distribution over time is dramatically favorable to Flash (especially TLC and QLC). I feel pretty comfortable keeping a ZFS drive pair (= mirrored) on the shelf for a decode or two whereas I'd abandon all hope for a modern SSD in the same conditions.
If tape was cheaper I'd consider that.