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Date: Fri, 07 Jun 2013 11:52:52 -0400
From: Quartz <quartz@sneakertech.com>
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Subject: ZFS: raid VS copies=n
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Question:

How does the ZFS option 'copies=n' and raid relate to and interact with 
each other? specifically recovery in the event of a failure. For 
example, is having three disks in a raid-1 configuration with copies=1 
effectively the same as having three disks in a raid-0 with copies=3? 
Are the copies distributed uniformly across all drives in the pool, or 
concentrated, or what? What happens with configs like a raid-z2 with 
copies=2? Which / how many disks can you lose?

(I'm aware that like a lot of other ZFS options copies=n doesn't have to 
be global to the entire pool / directory structure, but for the sake of 
simplicity let's assume it is in this case).

______________________________________
it has a certain smooth-brained appeal