zfs discuss - Apr 2007 - ZFS copies and fault tolerance

The filesystem allows to keep two or more copies of the data written. What
I''m interested in to know is how the placement of the copies is done.
Consider a JBOD pool, having set the filesystem to keep two copies, will the
copies be actively placed on two different volumes, as such allowing to survive
a device fault?

Thanks.
-mg
 
 
This message posted from opensolaris.org

See my blog on this topic:

    http://blogs.sun.com/bill/entry/ditto_blocks_the_amazing_tape

The quick summary is that if there is more than one vdev comprising the
pool, the copies will be spread across multiple vdevs.  If there is only
one, then the copies are spread out physically (at least by LBA) across
the device to handle localized media failure.


--Bill


On Sat, Apr 21, 2007 at 11:52:10AM -0700, Mario Goebbels
wrote:
> The filesystem allows to keep two or more copies of the data written.
> What I''m interested in to know is how the placement of the copies
is
> done. Consider a JBOD pool, having set the filesystem to keep two
> copies, will the copies be actively placed on two different volumes,
> as such allowing to survive a device fault?
> 
> Thanks.
> -mg
>  
>  
> This message posted from opensolaris.org
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> zfs-discuss mailing list
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