[kwlug-disc] Checking a USB disk for errors

[William Park]

On Thu, May 15, 2014 at 10:54:31PM -0400, Khalid Baheyeldin wrote:
> On Thu, May 15, 2014 at 9:55 PM, Khalid Baheyeldin <kb at 2bits.com> wrote:
> 
> > The method I used is to connect the drive to the laptop, unmount the NTFS
> > filesystem that is on it, and then do:
> >
> > time dd if=/dev/sdb bs=16mb of=/dev/null
> >
> 
> It is finally done ...
> 
> # time dd if=/dev/sdb bs=16000k of=/dev/null
> 61047+1 records in
> 61047+1 records out
> 1000204886016 bytes (1.0 TB) copied, 28626.2 s, 34.9 MB/s

34.9MB/s is pretty fast for USB2, but slow for USB3.  What I usually do
in this case is
    badblocks -b 4096 -c 4096 -sv ...
    badblocks -b 4096 -c 4096 -swv ...
where -w is for destructive read/write test.  

> 
> real    477m6.269s
> user    0m0.296s
> sys     19m33.457s
> 
> That is 7.95 hours ...
> -- 
> Khalid M. Baheyeldin
> 2bits.com, Inc.
> Fast Reliable Drupal
> Drupal optimization, development, customization and consulting.
> Simplicity is prerequisite for reliability. --  Edsger W.Dijkstra
> Simplicity is the ultimate sophistication. --   Leonardo da Vinci
> For every complex problem, there is an answer that is clear, simple, and
> wrong." -- H.L. Mencken

> _______________________________________________
> kwlug-disc mailing list
> kwlug-disc at kwlug.org
> http://kwlug.org/mailman/listinfo/kwlug-disc_kwlug.org