> On May 4, 2005, at 11:20 AM, Stephen Borrill wrote:
> > Got a RAID 1 set of identical Maxtor 6Y080M0 80GB S-ATA drives. One
> > seems to have developed a bad sector or two:
> >
> > wd2a: error reading fsbn 845648 of 845648-845663 (wd2 bn 847664; cn
> > 840 tn 14 sn 62)wd2: (uncorrectable data error)
> > [ ... ]
> > Is there any way to mark bad sectors in the underlying components so
> > that RAIDframe will ignore them? Is doing such a thing a sensible
> > move? bad144/badsect don't seem appropriate.
>
> No, it's not a sensible move.  Modern ATA drives already use ECC and
> migrate bad sectors to the spare sectors automaticly.  You don't see
> errors until the drive has had so many bad sectors appear that it has
> used up all of the replacement spare sectors.

Yes, but as I understand it, the drive will only swap that sector out
when it is written to. If a drive has developed a problem on a sector
such that it fails to read, it won't do anything else to that sector
until it is told to rewrite it with new data. And even then the sector
itself may be fine, it may simply be a case of the data having been
written incorrectly (off-track write) which can happen - we had a batch
of drives which exhibited this quite badly.