Re: [gentoo-user] using a HD with bad sectors

[Florian Philipp]

On Mon, 2008-05-05 at 11:14 +0800, Iain Buchanan wrote:
> Hi all,
>
> I have two 2.5in HD's, one 60Gb with a heap of bad sectors currently
> used in external Hd enclosure, and one 100Gb which seems in good
> condition, currently in my laptop.
>
> I'm upgrading my laptop, and I'd like to turn the old one into a myth
> frontend or something similar, so I want to put the 60Gb in it.  I will
> then use the 100Gb in my external enclosure for travelling, backups,
> etc.
>
> The reason the 60Gb has bad sectors (I think) is because I dropped it
> (in it's enclosure). This was quite some time ago, and it doesn't seem
> to be dying any further, but I haven't done any comparisons on the bad
> sector count.  I use nearly 100% of the space available, and regularly
> compare cksums, so if anything was deteriorating, I would know.
>
> The question is: should I use it at all (for any use, external HD or
> internal with operating system), or is it sufficient to let the fsck
> tool mark the bad sectors and just keep using it?
>
> Is there a way to monitor it's "health" in the external enclosure until
> I get my new laptop?  Is counting the bad sectors enough?
>

As I understand it, hard disks usually hide bad blocks from the OS as
long as they can utilize spare blocks. That means that there might be a
lot more bad blocks than you are aware of.

Last week I had my own notebook hard disk (60Gig as well) dying on me:
Bad blocks on a single partition, strange noises from time to time and
the S.M.A.R.T offline self test aborting with "read error" before it
even started.
I found smartmontools (or anything that's just polling SMART)
inappropriate. They still reported "all is well" although the self tests
failed (and were logged as failed) and an overheating occurrence was
logged (half a year ago the disk reached 53°C during normal operation
for no apparent reason). Bad blocks were not registered at all!