On Mon, 18 Jan 2010, Johnson,Robert E wrote:

> Not so much a fix as a preventative: in the old days (on other *nixes)
> it was often recommended that you do something like
>
> dd if=/dev/hda of=/dev/hda bs=128k
>
> once a month or so. This would refresh every sector of the drive in an
> attempt to remap bad sectors while they are still soft errors instead
> of hard errors, and could be run in the background at low priority.
> Modern filesystems might optimize this out to doing nothing, though.

I don't see how "modern filesystems" would optimize that out, since with 
dd operating on the devices, you're below the filesystem level.

Also, that seems like an incredibly dangerous thing to do on a device that 
has RW mounted partitions.  What if while reading a portion of /dev/hda, 
blocks change (due to filesystem activity) between dd's read and write? 
Now you've written old data back to the device and likely corrupted the 
filesystem.

----------------------------------------------------------------------
  Jon Lewis                   |  I route
  Senior Network Engineer     |  therefore you are
  Atlantic Net                |
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