I have been warranty/replace them when the sectors refuse to reallocate, and/or the disks continue to hit the ERC/TLER timeout all of the time with bad sectors growing rapidly with no end in sight. If one is using raid6 and given the low rate of bad sectors, then it is pretty unlikely that there will be data loss. If one was using raid5 things would be more worrisome. On Mon, Jan 31, 2022 at 1:21 PM Phil Turmel <philip@xxxxxxxxxx> wrote: > > On 1/31/22 14:07, Geoff Back wrote: > > > > > If a disk has one or more bad sectors, surely the only logical action is > > to schedule it for replacement as soon as a new one can be obtained; and > > if it's still in warranty, send it back. If the data is valuable enough > > to warrant use of RAID (along with, presumably, appropriate backups) > > surely it is too valuable to risk continuing to use a known faulty disk? > > > > In which case, I would suggest that dangerous experiments that try to > > force the disk to reallocate the block are arguably pointless. > > > > Just my opinion, but one that has served me well so far. > > > > Regards, > > > > Geoff. > > I would be surprised if you got warranty replacement just for a few > re-allocated sectors. The sheer quantity of sectors in modern drives > and the tiny magnetic domains involved means **no** drive is error-free. > Just most defects are identified and mapped out before shipping. > Reallocations cover the marginal cases. > > I replace drives when re-allocations hit double digits, though I've had > to run a few corners cases well past that point. > > Phil