RAID 1 or Hammer

Wed Jan 14 00:36:08 PST 2009

BjÃ¸rn Vermo wrote:
   I've seen uncaught data corruption on older machines, but not in the
   last few years.  Ah, the days of IDE cabling problems, remembered
   fondly (or not).  I've seen bad data get through TCP connections
   uncaught!  Yes, it actually does happen, even more so now that OS's
   are depending more and more on CRC checking done by the ethernet 
device.
...
Modern (meaning anything with an ATA or SCSI controller in it) drives 
will do so much error checking and recovery that the time between 
externally noticeable failures and total breakdown will be very short.
This seems to fail sometimes.  Recent work [1] has shown that silent data 
corruption on HDDs is larger than expected.

cheers
  simon
[1] Bairavasundaram et al., An Analysis of Data Corruption in the Storage 
Stack, USENIX FAST '08, 
<http://www.usenix.org/events/fast08/tech/full_papers/bairavasundaram/bairavasundaram_html/index.html> 
or 
<http://www.usenix.org/events/fast08/tech/full_papers/bairavasundaram/bairavasundaram.pdf>

Alternatively, easier read:
Bairavasundaram et al., Data Corruption in the Storage Stack: A Closer 
Look, USENIX ;login: June 2008, 
<http://www.usenix.org/publications/login/2008-06/openpdfs/bairavasundaram.pdf>

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