RAID 10, how layout works ?

Posted by Bastien974 on Server Fault See other posts from Server Fault or by Bastien974
Published on 2011-01-12T22:08:14Z Indexed on 2011/01/12 22:55 UTC
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linux

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mdadm

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raid10

I'm trying to figure out how exactly works the RAID 10 in linux with mdadm.

I want to create a RAID 10 out of 4 partitions, let's say a, b, c and d. a and b are on the array 1, c and d array 2.

So what I want is to have the couple a and b, c and d in RAID 0. Then on top of that, a RAID 1.

The option in the mdadm command to configure the layout is -p, --layout with option : near, far, offset see here

I want to keep my data safe if the array 1 fails for example, that would mean that every chunk of data are always copied on both arrays.

How do I have to set my RAID 10, near or far ?

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