[CentOS] hard drive errors

Kwan Lowe kwan.lowe at gmail.com
Tue Nov 24 15:46:22 UTC 2009


On Tue, Nov 24, 2009 at 4:16 AM, ken <gebser at mousecar.com> wrote:

> I get this kind of warning also, though the number of unreadable sectors
> I get is in the single digits.  All disks have some unreadable sectors.
>  It's just a product of the manufacturing process.

Interesting...I only get these when my drive is about to fail. In some
cases it took a week before the drive failed to the point that the
system was pausing, but most often failure occurred within a day or
two. It's a reliable enough indicator that I have my monitoring script
look specifically for these types of drive errors to make sure that I
don't miss any.


> A low-level format
> discovers these and marks and maps them so that they aren't used... so
> not a big deal.  (You are, after all, getting the message about them,
> right?)  So having unusable sectors isn't in itself a problem.  You've
> got a lot of them, but then perhaps your drive and the part of it you're
> using is much larger than mine.  If this 993 sectors is a considerable
> percentage of your disk, then you'd have cause to ask for a refund or
> exchange on the purchase, but still no real cause for alarm.  However,
> if that number of sectors increases over time, then you have a sign of a
> failing drive and obviously would want to replace it ASAP.

My understanding (which may be wrong) is that the drive electronics
automatically remapped the failing sectors. The point at which the OS
knows about it means that the drive is already out of reserve sectors.
Not sure if this is still the case.


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