Re: Docs and operation of RAID10, size limitations on 0.90

On Wed, Jul 30, 2008 at 4:49 PM, Richard Michael
[off-list ref] wrote:

Re-reading what I wrote, it's a mess of typos. :)  But, yes, I want to
remove half the disks on a regular basis, as off-site storage, and return
them to the array for periodic resync.

Basically what you want is a raid 51.
2x RAID5 (4 disks each) mirrored to form a RAID1.
Using bitmaps in the RAID1 would let you remove one of the RAID5, do
with it what you will, and add it back in again and only the changed
parts will get syncd.
At least in theory.

Look also into using drbd.

-- 
Jon