input/output error on disk(?)

[Tony Nelson]

On 09-10-15 16:28:03, charles zeitler wrote:
> thanks for the info.
> 
> On Thu, Oct 15, 2009 at 12:30 PM, Tony Nelson
> <tonynelson at georgeanelson.com> wrote:
> > On 09-10-15 01:29:22, charles zeitler wrote:
> >> when trying to copy a certain file, i get the message:
> >> cp: reading 'file' :  Input/output error
> >
> > It is likely that the disk has one or more bad blocks.  Use
> > `smartctl -a /dev/sdx` to see all the data (or -A to see only the
> > attributes) and look at the raw values of Current_Pending_Sector 
> > and Reallocated_Event_Count.  The first reflects unfixed problems, 
> > and the second fixed problems.  If both numbers are low,
> 
> 13 & 0

13 is a bit high considering that it reflects only the bad blocks that 
have been noticed, but it could still be from a single bad area.  The 
results from the long test will help decide.

> > I would just keep using the drive, though I would first do a long 
> > test with `smartctl -t long /dev/sdx` (wait until the indicated 
> > time and then do a `smartctl - a /dev/sdx` to see what happened)
> 
> should have more data from this in 4 hours.

OK.

> > and then enabled Automatic Offline
> > Testing with `smartctl -o on /dev/sdx` (this will help keep up with
> > sectors as they go bad, without unnecessary data loss).
> >
> > A program such as ddrescue (`yum install ddrescue`, `info 
> > ddrescue`) may help to salvage the damaged file(s).
>
> the file itself is not important, but i don't want the error
> to migrate to one that is..

That won't happen, as the drive will use a good block to replace the 
bad block when it is written to.  The real question is how many more 
blocks will go bad, and the long test should give a hint about that.

-- 
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