Re: With 4 disks should I go for RAID 5 or RAID 10

On Wed, 26 Dec 2007, Mark Mielke wrote:

> david@lang.hm 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