On Wed, 26 Dec 2007, Mark Mielke wrote:
david@xxxxxxx wrote:
I could see a raid 1 array not doing consistancy checking (after all, it
has no way of knowing what's right if it finds an error), but since raid
5/6 can repair the data I would expect them to do the checking each time.
Your messages are spread across the thread. :-)
RAID 5 cannot repair the data. I don't know much about RAID 6, but I expect
it cannot necessarily repair the data either. It still doesn't know which
drive is wrong. In any case, there is no implementation I am aware of that
performs mandatory consistency checks on read. This would be silliness.
sorry, raid 5 can repair data if it knows which chunk is bad (the same way
it can rebuild a drive). Raid 6 does something slightly different for it's
parity, I know it can recover from two drives going bad, but I haven't
looked into the question of it detecting bad data.
David Lang
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