Disk error??

[Alan Cox]

On Wed, 3 Mar 2010 11:02:41 +1100
L <yuanlux at gmail.com> wrote:

> Hi
> 
> The hard disk on a laptop shows failing error "Disk had many bad
> sectors' it suggests 'backup data and replace disk. Of course, this
> test information was generated by Palimpsest Disk Utility on F12.
> However, when I used self-test utility from BIOS (HP 6710), it passed
> all tests.
> 
> 
> Which result is reliable, one from Palimpsest Dish Utility or BIOS
> self-test utiltity?

Generally speaking the BIOS code asks the drive for its opinion and
displays that. It's usually as good a guide as you get for overall state.
If the drive vendors firmware with low level detailed access to the
innards can't tell then probably neither can anything else.

Remembering
- Many disk failures don't show up via SMART at all
- You only see the BIOS one at boot
- You should have a backup anyway because you might need it for other
  reasons (eg accidents as root)

Bad sectors are not neccessarily a problem (the drive will have replaced
them with spare ones when written). Unreadable sectors indicates a problem
somewhere - you have a sector 'live' on disk which cannot be re-read.

It's the trend that is likely to be more important. If it had 12 bad
sectors a year ago and it has 12 today why worry. If it had 1 last
week, 5 yesterday and 12 today then its a bit different.


Alan