[RAS] badblocks

[Christian Zimmermann]

Fine by me. But if you are just doing a local copy, why not use cp instead 
of rsync, as I believe cp is much less of a resource hog?

Christian Zimmermann                                     FIGUGEGL!
Department of Economics
University of Connecticut
341 Mansfield Road, Unit 1063
Storrs, CT 06269-1063
http://ideas.repec.org/zimm/   christian.zimmermann at uconn.edu
http://ideas.repec.org/e/pzi1.html

On Wed, 27 Feb 2008, Thomas Krichel wrote:

>
>  Christian Zimmermann writes
>
>> I am back and stand ready to run to the server farm if necessary.
>
>  With 11 hours time difference, I was in bed. I have been thinking
>  a bit more.
>
>  I remember, when I had a similar problem with raneb, there
>  were only 12 or 40 bad bad blocks, but they caused the disk
>  to crash. Now that the offending disk has been replaced, it's
>  all quiet on the raneb front. I would therefore suggest that
>  the troubles come from the bad block
>
>  The way I understand disks, is that decay is expenential.
>  Most modern disks have some extra space through RAID, that
>  is hidden from the O/S. When bad block appear the data is
>  moved from the bad blocks to blocks that are healthy, in
>  a way that is transparent to the o/s. When there are too
>  many bad blocks, the o/s start seeing them, and that's
>  when Linux gets rather merciless, it does not take hardware
>  issues lightly.
>
>  So even with 3 bad blocks, we need to get rid of the disk,
>  software updates will not help.
>
>  e2fsck has a -c option that will scan for bad blocks and
>  mark the bad blocks as bad, so that they are not used by the
>  o/s.  When we run this on startup, with the root file system
>  mounted read-only, it should mark the bad blocks. If
>  we then immediately (so that there are no further bad
>  blocks) rsync the files from sda to sdb, make sdb bootable,
>  then swap disks to boot from sdb, we should be fine.
>  I did such an operation locally and can give further
>  instructions if you agree with the general course of
>  action.
>
>
>  Cheers,
>
>  Thomas Krichel                    http://openlib.org/home/krichel
>                                RePEc:per:1965-06-05:thomas_krichel
>  phone: +7 383 330 6813                       skype: thomaskrichel
>